Supramolecular polymer

Last updated

In polymer chemistry and materials science, the term "polymer" refers to large molecules whose structure is composed of multiple repeating units. Supramolecular polymers are a new category of polymers that can potentially be used for material applications beyond the limits of conventional polymers. By definition, supramolecular polymers are polymeric arrays of monomeric units that are connected by reversible and highly directional secondary interactions–that is, non-covalent bonds. These non-covalent interactions include van der Waals interactions, hydrogen bonding, Coulomb or ionic interactions, π-π stacking, metal coordination, halogen bonding, chalcogen bonding, and host–guest interaction. [1] The direction and strength of the interactions are precisely tuned so that the array of molecules behaves as a polymer (that is, it behaves in a way that can be described by the theories of polymer physics) in dilute and concentrated solution, as well as in the bulk. [2]

Contents

In conventional polymers, monomeric units are linked by strong covalent bonds and have excellent properties as materials; however, high temperatures and pressures are typically required for processing due to polymer entanglement in the highly viscous melt. Supramolecular polymers combine good material properties with low-viscosity melts that are easy to handle. Additionally, some supramolecular polymers have unique characteristics, [3] [4] [5] such as the ability to self-heal fractures. Although covalent polymers can be recycled, their strong covalent bonds never disintegrate, and go on to negatively affect the environment as plastic wastes. Thus, supramolecular polymers are increasingly getting attention [6] because of their potential for the design of responsive, adaptive, self-healing, and environmentally friendly materials. [7] [8]

History

Monomeric motifs and types of interactions used for the preparation of supramolecular polymers Monomeric motifs of supramolecular polymer with their type of interactions.tiff
Monomeric motifs and types of interactions used for the preparation of supramolecular polymers

Modern concept of polymers credited to Hermann Staudinger, who substantiated the existence of covalently linked ultralong molecules in 1920, which he called as macromolecules. The preamble of the field of supramolecular polymers can be considered dye-aggregates and host-guest complexes. [9] In early 19th century, scientists working in the field of pigments have noticed certain dye aggregates that may formed via "a special kind of polymerization", however no theory was proposed. After the establishment of the field of supramolecular chemistry and after the award of the Nobel Prize in chemistry in 1987 to Donald J. Cram, Jean-Marie Lehn, and Charles J. Pedersen, chemists started to design and study larger assembled structures from small molecules. In 1988, Takuzo Aida, a Japanese polymer chemist, reported the concept of cofacial assembly wherein the amphiphilic porphyrin monomers are connected via van der Waals interaction forming one-dimensional architectures in solution, which can be considered as a prototype of supramolecular polymers. [10] In the same year 1988, James D. Wuest introduced one-dimensional aggregates based on hydrogen bonding interaction in the crystalline state. [11] With a different strategyusing hydrogen bonds, Jean M. J. Fréchet showed in 1989 that mesogenic molecules with carboxylic acid and pyridyl motifs, upon mixing in bulk, heterotropically dimerize to form a stable liquid crystalline structure. [12] In 1990, Jean-Marie Lehn showed that this strategy can be expanded to form a new category of polymers, which he called "liquid crystalline supramolecular polymer" using complementary triple hydrogen bonding motifs in bulk. [13] In 1993, M. Reza Ghadiri reported a nanotubular supramolecular polymer where a b-sheet-forming macrocyclic peptide monomer assembled together via multiple hydrogen bonding between adjacent macrocycles. [14] In 1994, Anselm. C. Griffin showed an amorphous supramolecular material using a single hydrogen bond between a homotropic molecules having carboxylic acid and pyridine termini. [15] The idea to make mechanically strong polymeric materials by 1D supramolecular association of small molecules requires a high association constant between the repeating building blocks. In 1997, E.W. "Bert" Meijer reported a telechelic monomer with ureidopyrimidinone termini as a "self-complementary" quadruple hydrogen bonding motif and demonstrated that the resulting supramolecular polymer in chloroform shows a temperature-dependent viscoelastic property in solution. [16] This is the first demonstration that supramolecular polymers, when sufficiently mechanically robust, are physically entangled in solution.

Formation mechanisms

Monomers undergoing supramolecular polymerization are considered to be in equilibrium with the growing polymers, and thermodynamic factors therefore dominate the system. [17] However, when the constituent monomers are connected via strong and multivalent interactions, a "metastable" kinetic state can dominate the polymerization. An externally supplied energy, in the form of heat in most cases, can transform the "metastable" state into a thermodynamically stable polymer. A clear understanding of multiple pathways exist in supramolecular polymerization is still under debate, however, the concept of "pathway complexity", introduced by E.W. "Bert" Meijer, shed a light on the kinetic behavior of supramolecular polymerization. [18] Thereafter, many dedicated scientists are expanding the scope of "pathway complexity" because it can produce a variety of interesting assembled structures from the same monomeric units. Along this line of kinetically controlled processes, supramolecular polymers having "stimuli-responsive" [19] and "thermally bisignate" characteristics is also possible. [20]

In conventional covalent polymerization, two models based on step-growth and chain-growth mechanisms are operative. Nowadays, a similar subdivision is acceptable for supramolecular polymerization; isodesmic also known as equal-K model (step-growth mechanism) and cooperative or nucleation-elongation model (chain-growth mechanism). A third category is seeded supramolecular polymerization, which can be considered as a special case of chain-growth mechanism.

Step-growth polymerization

Schematics of "pathway-complexity" and "chain-growth" mechanisms operative in supramolecular polymerization "Pathway complexity" and "chain-growth" mechanisms of supramolecular polymerization.tif
Schematics of "pathway-complexity" and "chain-growth" mechanisms operative in supramolecular polymerization

Supramolecular equivalent of step-growth mechanism is commonly known as isodesmic or equal-K model (K represents the total binding interaction between two neighboring monomers). In isodesmic supramolecular polymerization, no critical temperature or concentration of monomers is required for the polymerization to occur and the association constant between polymer and monomer is independent of the polymer chain length. Instead, the length of the supramolecular polymer chains rises as the concentration of monomers in the solution increases, or as the temperature decreases. In conventional polycondensation, the association constant is usually large that leads to a high degree of polymerization; however, a byproduct is observed. In isodesmic supramolecular polymerization, due to non-covalent bonding, the association between monomeric units is weak, and the degree of polymerization strongly depends on the strength of interaction, i.e. multivalent interaction between monomeric units. For instance, supramolecular polymers consisting of bifunctional monomers having single hydrogen bonding donor/acceptor at their termini usually end up with low degree of polymerization, however those with quadrupole hydrogen bonding, as in the case of ureidopyrimidinone motifs, result in a high degree of polymerization. In ureidopyrimidinone-based supramolecular polymer, the experimentally observed molecular weight at semi-dilute concentrations is in the order of 106 Dalton and the molecular weight of the polymer can be controlled by adding mono-functional chain-cappers.

Chain-growth polymerization

Conventional chain-growth polymerization involves at least two phases; initiation and propagation, while and in some cases termination and chain transfer phases also occur. Chain-growth supramolecular polymerization in a broad sense involves two distinct phases; a less favored nucleation and a favored propagation. In this mechanism, after the formation of a nucleus of a certain size, the association constant is increased, and further monomer addition becomes more favored, at which point the polymer growth is initiated. Long polymer chains will form only above a minimum concentration of monomer and below a certain temperature. However, to realize a covalent analogue of chain-growth supramolecular polymerization, a challenging prerequisite is the design of appropriate monomers that can polymerize only by the action of initiators. Recently one example of chain-growth supramolecular polymerization with "living" characteristics is demonstrated. [21] In this case, a bowl-shaped monomer with amide-appended side chains form a kinetically favored intramolecular hydrogen bonding network and does not spontaneously undergo supramolecular polymerization at ambient temperatures. [22] However, an N-methylated version of the monomer serves as an initiator by opening the intramolecular hydrogen bonding network for the supramolecular polymerization, just like ring-opening covalent polymerization. The chain end in this case remains active for further extension of supramolecular polymer and hence chain-growth mechanism allows for the precise control of supramolecular polymer materials.

Seeded polymerization

This is a special category of chain-growth supramolecular polymerization, where the monomer nucleates only in an early stage of polymerization to generate "seeds" and becomes active for polymer chain elongation upon further addition of a new batch of monomer. A secondary nucleation is suppressed in most of the case and thus possible to realize a narrow polydispersity of the resulting supramolecular polymer. In 2007, Ian Manners and Mitchell A. Winnik introduced this concept using a polyferrocenyldimethylsilane–polyisoprene diblock copolymer as the monomer, which assembles into cylindrical micelles. [23] When a fresh feed of the monomer is added to the micellar "seeds" obtained by sonication, the polymerization starts in a living polymerization manner. They named this method as crystallization-driven self-assembly (CDSA) and is applicable to construct micron-scale supramolecular anisotropic structures in 1D–3D. A conceptually different seeded supramolecular polymerization was shown by Kazunori Sugiyasu in a porphyrin-based monomer bearing amide-appended long alkyl chains. [24] At low temperature, this monomer preferentially forms spherical J-aggregates while fibrous H-aggregates at higher temperature. By adding a sonicated mixture of the J-aggregates ("seeds") into a concentrated solution of the J-aggregate particles, long fibers can be prepared via living seeded supramolecular polymerization. Frank Würthner achieved similar seeded supramolecular polymerization of amide functionalized perylene bisimide as monomer. [25] Importantly, the seeded supramolecular polymerization is also applicable to prepare supramolecular block copolymers.

Examples

Hydrogen bonding interaction

Monomers capable of forming single, double, triple or quadruple hydrogen bonding has been utilized for making supramolecular polymers, and increased association of monomers obviously possible when monomers have maximum number of hydrogen bonding donor/acceptor motifs. For instance, ureidopyrimidinone-based monomer with self-complementary quadruple hydrogen bonding termini polymerized in solution, accordingly with the theory of conventional polymers and displayed a distinct viscoelastic nature at ambient temperatures.

π-π stacking

Monomers with aromatic motifs such as bis(merocyanine), oligo(para-phenylenevinylene) (OPV), perylene bisimide (PBI) dye, cyanine dye, corannulene and nano-graphene derivatives have been employed to prepare supramolecular polymers. In some cases, hydrogen bonding side chains appended onto the core aromatic motif help to hold the monomer strongly in the supramolecular polymer. A notable system in this category is a nanotubular supramolecular polymer formed by the supramolecular polymerization of amphiphilic hexa-peri-hexabenzocoronene (HBC) derivatives. [26] Generally, nanotubes are categorized as 1D objects morphologically, however, their walls adopt a 2D geometry and therefore require a different design strategy. [27] HBC amphiphiles in polar solvents solvophobically assemble into a 2D bilayer membrane, which roles up into a helical tape or a nanotubular polymer. Conceptually similar amphiphilic design based on cyanine dye and zinc chlorin dye also polymerize in water resulting in nanotubular supramolecular polymers. [28] [29]

Host-guest interaction

A variety of supramolecular polymers can be synthesized by using monomers with host-guest complementary binding motifs, such as crown ethers/ammonium ions, cucurbiturils/viologens, calixarene/viologens, cyclodextrins/adamantane derivatives, and pillar arene/imidazolium derivatives [30–33]. [30] [31] [32] When the monomers are "heteroditopic", supramolecular copolymers results, provided the monomers does not homopolymerize. Akira Harada was one of the firstwhorecognize the importance of combining polymers and cyclodextrins. [33] Feihe Huang showed an example of supramolecular alternating copolymer from two heteroditopic monomers carrying both crown ether and ammonium ion termini. [34] Takeharo Haino demonstrated an extreme example of sequence control in supramolecular copolymer, where three heteroditopic monomers are arranged in an ABC sequence along the copolymer chain. [35] The design strategy utilizing three distinct binding interactions; ball-and-socket (calix[5]arene/C60), donor-acceptor (bisporphyrin/trinitrofluorenone), and Hamilton's H-bonding interactions is the key to attain a high orthogonality to form an ABC supramolecular terpolymer.

Chirality

Stereochemical information of a chiral monomer can be expressed in a supramolecular polymer. [36] Helical supramolecular polymer with P-and M-conformation are widely seen, especially those composed of disc-shaped monomers. When the monomers are achiral, both P-and M-helices are formed in equal amounts. When the monomers are chiral, typically due to the presence of one or more stereocenters in the side chains, the diastereomeric relationship between P- and M-helices leads to the preference of one conformation over the other. Typical example is a C3-symmetric disk-shaped chiral monomer that forms helical supramolecular polymers via the "majority rule". A slight excess of one enantiomer of the chiral monomer resulted in a strong bias to either the right-handed or left-handed helical geometry at the supramolecular polymer level. [37] In this case, a characteristic nonlinear dependence of the anisotropic factor, g, on the enantiomeric excess of a chiral monomer can be generally observed. Like in small molecule based chiral system, chirality of a supramolecular polymer also affected by chiral solvents. Some application such as a catalyst for asymmetric synthesis [38] and circular polarized luminescence are observed in chiral supramolecular polymers too.

Copolymers

A copolymer is formed from more than one monomeric species. Advanced polymerization techniques have been established for the preparation of covalent copolymers, however supramolecular copolymers are still in its infancy and is slowly progressing. In recent years, all plausible category of supramolecular copolymers such as random, alternating, block, blocky, or periodic has been demonstrated in a broad sense. [39]

Properties

Supramolecular polymers are the subject of research in academia and industry.

Reversibility and dynamicity

The stability of a supramolecular polymer can be described using the association constant, Kass. When Kass ≤ 104M−1, the polymeric aggregates are typically small in size and do not show any interesting properties and when Kass≥ 1010 M−1, the supramolecular polymer behaves just like covalent polymers due to the lack of dynamics. So, an optimum Kass = 104–1010M−1need to be attained for producing functional supramolecular polymers. The dynamics and stability of the supramolecular polymers often affect by the influence of additives (e.g. co-solvent or chain-capper). When a good solvent, for instance chloroform, is added to a supramolecular polymer in a poor solvent, for instance heptane, the polymer disassembles. However, in some cases, cosolvents contribute the stabilization/destabilization of supramolecular polymer. For instance, supramolecular polymerization of a hydrogen bonding porphyrin-based monomer in a hydrocarbon solvent containing a minute amount of a hydrogen bond scavenging alcohol shows distinct pathways, i.e. polymerization favored both by cooling as well as heating, and is known as "thermally bisignate supramolecular polymerization". In another example, minute amounts of molecularly dissolved water molecules in apolar solvents, like methylcyclohexane, become part of the supramolecular polymer at lower temperatures, due to specific hydrogen bonding interaction between the monomer and water. [40]

Self-healing

Supramolecular polymers may be relevant to self-healing materials. [41] A supramolecular rubber based on vitrimers can self-heal simply by pressing the two broken edges of the material together. [42] High mechanical strength of a material and self-healing ability are generally mutually exclusive. Thus, a glassy material that can self-heal at room temperature remained a challenge until recently. A supramolecularly polymer based on ether-thiourea is mechanically robust (e= 1.4 GPa) but can self-heal at room temperature by a compression at the fractured surfaces. [43] The invention of self-healable polymer glass updated the preconception that only soft rubbery materials can heal.

Examples of hydrogen-bonding based self-healing 'supramolecular rubber' (a) and 'polymer glass' (b). Supramolecular rubber and polymer glass.tif
Examples of hydrogen-bonding based self-healing 'supramolecular rubber' (a) and 'polymer glass' (b).

Another strategy uses a bivalent poly(isobutylene)s (PIBs) functionalized with barbituric acid at head and tail. [44] Multiple hydrogen bonding existed between the carbonyl group and amide group of barbituric acid enable it to form a supramolecular network. In this case, the snipped small PIBs-based disks can recover itself from mechanical damage after several-hour contact at room temperature.

Interactions between catechol and ferric ions exhibit pH-controlled self-healing supramolecular polymers. [45] The formation of mono-, bis- and triscatehchol-Fe3+ complexes can be manipulated by pH, of which the bis- and triscatehchol-Fe3+ complexes show elastic moduli as well as self-healing capacity. For example, the triscatehchol-Fe3+ can restore its cohesiveness and shape after being torn. Chain-folding polyimide and pyrenyl-end-capped chains give rise to supramolecular networks. [46]

Optoelectronic

By incorporating electron donors and electron acceptors into the supramolecular polymers, features of artificial photosynthesis can be replicated. [47] [2]

Biocompatible

DNA is a major example of a supramolecular polymer. [48] protein [49] Much effort has been develoted to related but synthetic materials. [50] At the same time, their reversible and dynamic nature make supramolecular polymers bio-degradable, [51] [52] which surmounts hard-to-degrade issue of covalent polymers and makes supramolecular polymers a promising platform for biomedical applications. Being able to degrade in biological environment lowers potential toxicity of polymers to a great extent and therefore, enhances biocompatibility of supramolecular polymers. [53] [54]

Biomedical applications

With the excellent nature in biodegradation and biocompatibility, supramolecular polymers show great potential in the development of drug delivery, gene transfection and other biomedical applications. [50]

Drug delivery: Multiple cellular stimuli could induce responses in supramolecular polymers. [55] [56] [50] The dynamic molecular skeletons of supramolecular polymers can be depolymerized when exposing to the external stimuli like pH in vivo. On the basis of this property, supramolecular polymers are capable of being a drug carrier. Making use of hydrogen bonding between nucleobases to induce self-assemble into pH-sensitive spherical micelles.

Gene transfection: Effective and low-toxic nonviral cationic vectors are highly desired in the field of gene therapy. [50] On account of the dynamic and stimuli-responsive properties, supramolecular polymers offer a cogent platform to construct vectors for gene transfection. By combining ferrocene dimer with β-cyclodextrin dimer, a redox-control supramolecular polymers system has been proposed as a vector. In COS-7 cells, this supramolecular polymersic vector can release enclosed DNA upon exposing to hydrogen peroxide and achieve gene transfection. [57]

Adjustable mechanical properties

Association and dissociation kinetics for polymer dynamics Association and dissociation kinetics for polymer.png
Association and dissociation kinetics for polymer dynamics
  1. Basic Principle : Noncovalent interactions between polymer molecules significantly affect the mechanical properties of supramolecular polymers. More interaction between polymers tends to enhance the interaction strength between polymers. The association rate and dissociation rate of interacting groups in polymer molecules determine intermolecular interaction strength. For supramolecular polymers, the dissociation kinetics for dynamic networks plays a critical role in the material design and mechanical properties of the SPNs(supramolecular polymer networks). [58] By changing the dissociation rate of polymer crosslink dynamics, supramolecular polymers have adjustable mechanical properties. With a slow dissociation rate for dynamic networks of supramolecular polymers, glass-like mechanical properties are dominant, on the other hand, rubber-like mechanical properties are dominant for a fast dissociation rate. These properties can be obtained by changing the molecular structure of the crosslink part of the molecule.
  2. Experimental examples : One research controlled the molecular design of cucurbit[8]uril, CB[8]. The hydrophobic structure of the second guest of CB-mediated host-guest interaction within its molecular structure can tune the dissociative kinetics of the dynamic crosslinks. To slow the dissociation rate (kd), a stronger enthalpic driving force is needed for the second guest association (ka) to release more of the conformationally restricted water from the CB(8] cavity. [59] In other words, the hydrophobic second guest exhibited the highest Keq and lowest kd values. Therefore, by polymerizing different concentrations of polymer subgroups, different dynamics of the intermolecular network can be designed.For example, mechanical properties like compressive strain can be tuned by this process. Polymerized with different hydrophobic subgroups in CB[B], The compressive strength was found to increase across the series in correlation with a decrease of kd, which could be tuned between 10–100MPa. [60] NVI, is the most hydrophobic subgroup structure of monomer which have two benzene rings, on the other hand, BVI is the least hydrophobic subgroup structure of monomer via control group. Besides, varying concentrations of hydrophobic subgroups in CB[B], polymerized molecules show different compressive properties. Polymers with the highest concentration of hydrophobic subgroups show the highest compressive strain and vice versa.

Biomaterials

Supramolecular polymers with specific, directional, tunable and reversible non-covalent interactions should be advantageous for biomaterials as well as biomedical applications. For instance, the reversible nature of supramolecular polymers can produce biomaterials that can sense and respond to physiological cues, or that mimic the structural and functional aspects of biological signaling. On the basis of their formation mechanisms, supramolecular biomaterials can be broadly classified as: (1) materials prepared from one-dimensional assemblies of molecular stacking motifs as in the case of peptide amphiphiles introduced by Samuel I. Stupp, [61] and (2) materials prepared through chain extension of oligomers or through crosslinking of polymeric precursors by specific supramolecular recognition motifs. [62]

Rationally designed supramolecular polymers-based polymers can simultaneously meet the requirements of aqueous compatibility, bio-degradability, biocompatibility, stimuli-responsiveness and other strict criterion. [50] Consequently, supramolecular polymers can be applied to the biomedical field as a robust system. Other than applications mentioned above, other important and fascinating biomedical applications, like protein delivery, [63] [64] bio-imaging and diagnosis [65] [66] and tissue engineering, [67] [68] are also well developed.

Conceptual expansion

Unconventional monomers

Over the time, methods for supramolecular polymerization has expanded, and the range of its useable monomers has diversified. In addition to plethora of molecular motifs, biomolecules such as DNA, DNA nanostructures and proteins as well as inorganic objects as unconventional monomers has recently been investigated for supramolecular polymerization. In all of these cases, monomers are in much higher size, usually several nanometers, and the non-covalent interactions varies from hydrogen bonding, host-guest and metal coordination. [69] A notable example is Mg2+-assisted multivalent supramolecular polymerization of ATP-responsive biomolecular machines, chaperonine GroEL, resulting in a highly stable protein nanotube. [70] Importantly, this nanotube shows an ATPase activity and dissociates into short-chain oligomers when treated with ATP because of the opening/closing motions of the constituent GroEL units.

Unconventional media

Supramolecular polymers usually prepared in solution. However anomalous polymeric properties can be expected when these polymers are prepared without a conventional organic or aqueous medium. For instance, liquid crystal media may affect the elementary steps of supramolecular polymerization as demonstrated by Takashi Kato in 1998, in the supramolecular crosslinking polymerization of physical gelators, which form a liquid crystal physical gel. [71] When monomers are designed to be highly affinitive toward the LC media, supramolecular polymerization causes an order-increasing phase transition, resulting in a core-shell columnar LC. [72] Supramolecular polymers can also be prepared in the solid-state, for instance, a nucleobase-appended telechelic oligomer as a monomer, resulted in the formation of 1D fibers upon cooling from its hot melt. As a new class of materials, supramolecular polymers formed at electrode and at the interface also become available.

Related Research Articles

<span class="mw-page-title-main">Hydrogen bond</span> Intermolecular attraction between a hydrogen-donor pair and an acceptor

In chemistry, a hydrogen bond is primarily an electrostatic force of attraction between a hydrogen (H) atom which is covalently bonded to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a lone pair of electrons—the hydrogen bond acceptor (Ac). Such an interacting system is generally denoted Dn−H···Ac, where the solid line denotes a polar covalent bond, and the dotted or dashed line indicates the hydrogen bond. The most frequent donor and acceptor atoms are the period 2 elements nitrogen (N), oxygen (O), and fluorine (F).

<span class="mw-page-title-main">Polymer</span> Substance composed of macromolecules with repeating structural units

A polymer (;) is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals.

<span class="mw-page-title-main">Micelle</span> Group of fatty molecules suspended in liquid by soaps and/or detergents

A micelle or micella is an aggregate of surfactant amphipathic lipid molecules dispersed in a liquid, forming a colloidal suspension. A typical micelle in water forms an aggregate with the hydrophilic "head" regions in contact with surrounding solvent, sequestering the hydrophobic single-tail regions in the micelle centre.

<span class="mw-page-title-main">Copolymer</span> Polymer derived from more than one species of monomer

In polymer chemistry, a copolymer is a polymer derived from more than one species of monomer. The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are sometimes called bipolymers. Those obtained from three and four monomers are called terpolymers and quaterpolymers, respectively. Copolymers can be characterized by a variety of techniques such as NMR spectroscopy and size-exclusion chromatography to determine the molecular size, weight, properties, and composition of the material.

Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the energy parameters of the component. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi–pi interactions and electrostatic effects.

<span class="mw-page-title-main">Polycatenane</span> Mechanically interlocked molecular architecture

A polycatenane is a chemical substance that, like polymers, is chemically constituted by a large number of units. These units are made up of concatenated rings into a chain-like structure.

<span class="mw-page-title-main">Host–guest chemistry</span> Supramolecular structures held together other than by covalent bonds

In supramolecular chemistry, host–guest chemistry describes complexes that are composed of two or more molecules or ions that are held together in unique structural relationships by forces other than those of full covalent bonds. Host–guest chemistry encompasses the idea of molecular recognition and interactions through non-covalent bonding. Non-covalent bonding is critical in maintaining the 3D structure of large molecules, such as proteins and is involved in many biological processes in which large molecules bind specifically but transiently to one another.

<span class="mw-page-title-main">Supramolecular assembly</span> Complex of molecules non-covalently bound together

In chemistry, a supramolecular assembly is a complex of molecules held together by noncovalent bonds. While a supramolecular assembly can be simply composed of two molecules, or a defined number of stoichiometrically interacting molecules within a quaternary complex, it is more often used to denote larger complexes composed of indefinite numbers of molecules that form sphere-, rod-, or sheet-like species. Colloids, liquid crystals, biomolecular condensates, micelles, liposomes and biological membranes are examples of supramolecular assemblies, and their realm of study is known as supramolecular chemistry. The dimensions of supramolecular assemblies can range from nanometers to micrometers. Thus they allow access to nanoscale objects using a bottom-up approach in far fewer steps than a single molecule of similar dimensions.

<span class="mw-page-title-main">Molecular imprinting</span> Technique in polymer chemistry

Molecular imprinting is a technique to create template-shaped cavities in polymer matrices with predetermined selectivity and high affinity. This technique is based on the system used by enzymes for substrate recognition, which is called the "lock and key" model. The active binding site of an enzyme has a shape specific to a substrate. Substrates with a complementary shape to the binding site selectively bind to the enzyme; alternative shapes that do not fit the binding site are not recognized.

<span class="mw-page-title-main">Salt bridge (protein and supramolecular)</span> Combination of hydrogen and ionic bonding in chemistry

In chemistry, a salt bridge is a combination of two non-covalent interactions: hydrogen bonding and ionic bonding. Ion pairing is one of the most important noncovalent forces in chemistry, in biological systems, in different materials and in many applications such as ion pair chromatography. It is a most commonly observed contribution to the stability to the entropically unfavorable folded conformation of proteins. Although non-covalent interactions are known to be relatively weak interactions, small stabilizing interactions can add up to make an important contribution to the overall stability of a conformer. Not only are salt bridges found in proteins, but they can also be found in supramolecular chemistry. The thermodynamics of each are explored through experimental procedures to access the free energy contribution of the salt bridge to the overall free energy of the state.

<span class="mw-page-title-main">Crystal engineering</span> Designing solid structures with tailored properties

Crystal engineering studies the design and synthesis of solid-state structures with desired properties through deliberate control of intermolecular interactions. It is an interdisciplinary academic field, bridging solid-state and supramolecular chemistry.

<span class="mw-page-title-main">Self-healing material</span> Substances that can repair themselves

Self-healing materials are artificial or synthetically created substances that have the built-in ability to automatically repair damages to themselves without any external diagnosis of the problem or human intervention. Generally, materials will degrade over time due to fatigue, environmental conditions, or damage incurred during operation. Cracks and other types of damage on a microscopic level have been shown to change thermal, electrical, and acoustical properties of materials, and the propagation of cracks can lead to eventual failure of the material. In general, cracks are hard to detect at an early stage, and manual intervention is required for periodic inspections and repairs. In contrast, self-healing materials counter degradation through the initiation of a repair mechanism that responds to the micro-damage. Some self-healing materials are classed as smart structures, and can adapt to various environmental conditions according to their sensing and actuation properties.

In chemistry, a halogen bond occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a halogen atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity. Like a hydrogen bond, the result is not a formal chemical bond, but rather a strong electrostatic attraction. Mathematically, the interaction can be decomposed in two terms: one describing an electrostatic, orbital-mixing charge-transfer and another describing electron-cloud dispersion. Halogen bonds find application in supramolecular chemistry; drug design and biochemistry; crystal engineering and liquid crystals; and organic catalysis.

<span class="mw-page-title-main">Takuzo Aida</span> Japanese polymer chemist

Takuzo Aida is a polymer chemist known for his work in the fields of supramolecular chemistry, materials chemistry and polymer chemistry. Aida, who is the Deputy Director for the RIKEN Center for Emergent Matter Science (CEMS) and a Distinguished University Professor at the University of Tokyo, has made pioneering contributions to the initiation, fundamental progress, and conceptual expansion of supramolecular polymerization. Aida has also been a leader and advocate for addressing critical environmental issues caused by plastic waste and microplastics in the oceans, soil, and food supply, through the development of dynamic, responsive, healable, reorganizable, and adaptive supramolecular polymers and related soft materials.

<span class="mw-page-title-main">Peptide amphiphile</span>

Peptide amphiphiles (PAs) are peptide-based molecules that self-assemble into supramolecular nanostructures including; spherical micelles, twisted ribbons, and high-aspect-ratio nanofibers. A peptide amphiphile typically comprises a hydrophilic peptide sequence attached to a lipid tail, i.e. a hydrophobic alkyl chain with 10 to 16 carbons. Therefore, they can be considered a type of lipopeptide. A special type of PA, is constituted by alternating charged and neutral residues, in a repeated pattern, such as RADA16-I. The PAs were developed in the 1990s and the early 2000s and could be used in various medical areas including: nanocarriers, nanodrugs, and imaging agents. However, perhaps their main potential is in regenerative medicine to culture and deliver cells and growth factors.

<span class="mw-page-title-main">Two-dimensional polymer</span>

A two-dimensional polymer (2DP) is a sheet-like monomolecular macromolecule consisting of laterally connected repeat units with end groups along all edges. This recent definition of 2DP is based on Hermann Staudinger's polymer concept from the 1920s. According to this, covalent long chain molecules ("Makromoleküle") do exist and are composed of a sequence of linearly connected repeat units and end groups at both termini.

<span class="mw-page-title-main">Self-healing hydrogels</span> Type of hydrogel

Self-healing hydrogels are a specialized type of polymer hydrogel. A hydrogel is a macromolecular polymer gel constructed of a network of crosslinked polymer chains. Hydrogels are synthesized from hydrophilic monomers by either chain or step growth, along with a functional crosslinker to promote network formation. A net-like structure along with void imperfections enhance the hydrogel's ability to absorb large amounts of water via hydrogen bonding. As a result, hydrogels, self-healing alike, develop characteristic firm yet elastic mechanical properties. Self-healing refers to the spontaneous formation of new bonds when old bonds are broken within a material. The structure of the hydrogel along with electrostatic attraction forces drive new bond formation through reconstructive covalent dangling side chain or non-covalent hydrogen bonding. These flesh-like properties have motivated the research and development of self-healing hydrogels in fields such as reconstructive tissue engineering as scaffolding, as well as use in passive and preventive applications.

<span class="mw-page-title-main">Polyrotaxane</span>

Polyrotaxane is a type of mechanically interlocked molecule consisting of strings and rings, in which multiple rings are threaded onto a molecular axle and prevented from dethreading by two bulky end groups. As oligomeric or polymeric species of rotaxanes, polyrotaxanes are also capable of converting energy input to molecular movements because the ring motions can be controlled by external stimulus. Polyrotaxanes have attracted much attention for decades, because they can help build functional molecular machines with complicated molecular structure.

<span class="mw-page-title-main">Macromolecular cages</span>

Macromolecular cages have three dimensional chambers surrounded by a molecular framework. Macromolecular cage architectures come in various sizes ranging from 1-50 nm and have varying topologies as well as functions. They can be synthesized through covalent bonding or self-assembly through non-covalent interactions. Most macromolecular cages that are formed through self-assembly are sensitive to pH, temperature, and solvent polarity.

<span class="mw-page-title-main">Topochemical polymerization</span>

Topochemical polymerization is a polymerization method performed by monomers aligned in the crystal state. In this process, the monomers are crystallised and polymerised under external stimuli such as heat, light, or pressure. Compared to traditional polymerisation, the movement of monomers was confined by the crystal lattice in topochemical polymerisation, giving rise to polymers with high crystallinity, tacticity, and purity. Topochemical polymerisation can also be used to synthesise unique polymers such as polydiacetylene that are otherwise hard to prepare.

References

  1. ↑ Brunsveld L, Folmer BJ, Meijer EW, Sijbesma RP (December 2001). "Supramolecular polymers". Chemical Reviews. 101 (12): 4071–4098. doi:10.1021/cr990125q. PMID   11740927.
  2. 1 2 De Greef TF, Smulders MM, Wolffs M, Schenning AP, Sijbesma RP, Meijer EW (November 2009). "Supramolecular polymerization". Chemical Reviews. 109 (11): 5687–5754. doi:10.1021/cr900181u. PMID   19769364.
  3. ↑ Aida T, Meijer EW, Stupp SI (February 2012). "Functional supramolecular polymers". Science. 335 (6070): 813–817. Bibcode:2012Sci...335..813A. doi:10.1126/science.1205962. PMC   3291483 . PMID   22344437.
  4. ↑ Aida T (May 2020). "On Supramolecular Polymerization: Interview with Takuzo Aida". Advanced Materials. 32 (20): e1905445. doi:10.1002/adma.201905445. PMID   31867791.
  5. ↑ Aida T, Meijer EW (January 2020). "Supramolecular Polymers – we've Come Full Circle". Israel Journal of Chemistry. 60 (1–2): 33–47. doi:10.1002/ijch.201900165. ISSN   0021-2148.
  6. ↑ Hashim PK, Bergueiro J, Meijer EW, Aida T (2020-06-01). "Supramolecular Polymerization: A Conceptual Expansion for Innovative Materials". Progress in Polymer Science. 105: 101250. doi:10.1016/j.progpolymsci.2020.101250. ISSN   0079-6700.
  7. ↑ Amabilino DB, Smith DK, Steed JW (May 2017). "Supramolecular materials" (PDF). Chemical Society Reviews. 46 (9): 2404–2420. doi:10.1039/c7cs00163k. PMID   28443937. S2CID   206086133.
  8. ↑ Yang L, Tan X, Wang Z, Zhang X (August 2015). "Supramolecular Polymers: Historical Development, Preparation, Characterization, and Functions". Chemical Reviews. 115 (15): 7196–7239. doi:10.1021/cr500633b. PMID   25768045.
  9. ↑ Wehner M, Würthner F (2019-12-21). "Supramolecular polymerization through kinetic pathway control and living chain growth". Nature Reviews Chemistry. 4 (1): 38–53. doi:10.1038/s41570-019-0153-8. ISSN   2397-3358. S2CID   209432740.
  10. ↑ Aida T, Takemura A, Fuse M, Inoue S (1988). "Synthesis of a novel amphiphilic porphyrin carrying water-soluble polyether side chains of controlled chain length. Formation of a cofacial molecular assembly in aqueous media". Journal of the Chemical Society, Chemical Communications (5): 391. doi:10.1039/c39880000391. ISSN   0022-4936.
  11. ↑ Ducharme Y, Wuest JD (November 1988). "Use of hydrogen bonds to control molecular aggregation. Extensive, self-complementary arrays of donors and acceptors". The Journal of Organic Chemistry. 53 (24): 5787–5789. doi:10.1021/jo00259a037. ISSN   0022-3263.
  12. ↑ Kato T, Takashi JM (October 1989). "A new approach to mesophase stabilization through hydrogen bonding molecular interactions in binary mixtures". Journal of the American Chemical Society. 111 (22): 8533–8534. doi:10.1021/ja00204a044. ISSN   0002-7863.
  13. ↑ Fouquey C, Lehn JM, Levelut AM (May 1990). "Molecular recognition directed self-assembly of supramolecular liquid crystalline polymers from complementary chiral components". Advanced Materials. 2 (5): 254–257. doi:10.1002/adma.19900020506. ISSN   0935-9648.
  14. ↑ Ghadiri MR, Granja JR, Milligan RA, McRee DE, Khazanovich N (November 1993). "Self-assembling organic nanotubes based on a cyclic peptide architecture". Nature. 366 (6453): 324–327. Bibcode:1993Natur.366..324G. doi:10.1038/366324a0. PMID   8247126. S2CID   4367103.
  15. ↑ Lee CM, Jariwala CP, Griffin AC (October 1994). "Heteromeric liquid-crystalline association chain polymers: structure and properties". Polymer. 35 (21): 4550–4554. doi:10.1016/0032-3861(94)90801-x. ISSN   0032-3861.
  16. ↑ Sijbesma RP, Beijer FH, Brunsveld L, Folmer BJ, Hirschberg JH, Lange RF, et al. (November 1997). "Reversible polymers formed from self-complementary monomers using quadruple hydrogen bonding" (PDF). Science. 278 (5343): 1601–1604. Bibcode:1997Sci...278.1601S. doi:10.1126/science.278.5343.1601. PMID   9374454.
  17. ↑ Sorrenti A, Leira-Iglesias J, Markvoort AJ, de Greef TF, Hermans TM (September 2017). "Non-equilibrium supramolecular polymerization". Chemical Society Reviews. 46 (18): 5476–5490. doi: 10.1039/c7cs00121e . PMC   5708531 . PMID   28349143.
  18. ↑ Korevaar PA, George SJ, Markvoort AJ, Smulders MM, Hilbers PA, Schenning AP, et al. (January 2012). "Pathway complexity in supramolecular polymerization". Nature. 481 (7382): 492–496. Bibcode:2012Natur.481..492K. doi:10.1038/nature10720. PMID   22258506. S2CID   4412624.
  19. ↑ Jain A, Dhiman S, Dhayani A, Vemula PK, George SJ (January 2019). "Chemical fuel-driven living and transient supramolecular polymerization". Nature Communications. 10 (1): 450. Bibcode:2019NatCo..10..450J. doi: 10.1038/s41467-019-08308-9 . PMC   6347607 . PMID   30683874.
  20. ↑ Venkata Rao K, Miyajima D, Nihonyanagi A, Aida T (November 2017). "Thermally bisignate supramolecular polymerization". Nature Chemistry. 9 (11): 1133–1139. Bibcode:2017NatCh...9.1133V. doi:10.1038/nchem.2812. PMID   29064499.
  21. ↑ Kang J, Miyajima D, Mori T, Inoue Y, Itoh Y, Aida T (February 2015). "Noncovalent assembly. A rational strategy for the realization of chain-growth supramolecular polymerization". Science. 347 (6222): 646–651. Bibcode:2015Sci...347..646K. doi:10.1126/science.aaa4249. PMID   25657246. S2CID   8487579.
  22. ↑ Kang J, Miyajima D, Itoh Y, Mori T, Tanaka H, Yamauchi M, et al. (July 2014). "C5-symmetric chiral corannulenes: desymmetrization of bowl inversion equilibrium via "intramolecular" hydrogen-bonding network". Journal of the American Chemical Society. 136 (30): 10640–10644. doi:10.1021/ja505941b. PMID   25046475.
  23. ↑ Wang X, Guerin G, Wang H, Wang Y, Manners I, Winnik MA (August 2007). "Cylindrical block copolymer micelles and co-micelles of controlled length and architecture". Science. 317 (5838): 644–647. Bibcode:2007Sci...317..644W. doi:10.1126/science.1141382. PMID   17673656. S2CID   10616507.
  24. ↑ Ogi S, Sugiyasu K, Manna S, Samitsu S, Takeuchi M (March 2014). "Living supramolecular polymerization realized through a biomimetic approach". Nature Chemistry. 6 (3): 188–195. Bibcode:2014NatCh...6..188O. doi:10.1038/nchem.1849. PMID   24557132. S2CID   205292495.
  25. ↑ Wagner W, Wehner M, Stepanenko V, Ogi S, Würthner F (December 2017). "Living Supramolecular Polymerization of a Perylene Bisimide Dye into Fluorescent J-Aggregates". Angewandte Chemie. 56 (50): 16008–16012. doi:10.1002/anie.201709307. PMID   29035005.
  26. ↑ Hill JP, Jin W, Kosaka A, Fukushima T, Ichihara H, Shimomura T, et al. (June 2004). "Self-assembled hexa-peri-hexabenzocoronene graphitic nanotube". Science. 304 (5676): 1481–1483. Bibcode:2004Sci...304.1481H. doi:10.1126/science.1097789. PMID   15178796. S2CID   39674411.
  27. ↑ Shimizu T, Masuda M, Minamikawa H (April 2005). "Supramolecular nanotube architectures based on amphiphilic molecules". Chemical Reviews. 105 (4): 1401–1443. doi:10.1021/cr030072j. PMID   15826016.
  28. ↑ Eisele DM, Cone CW, Bloemsma EA, Vlaming SM, van der Kwaak CG, Silbey RJ, et al. (July 2012). "Utilizing redox-chemistry to elucidate the nature of exciton transitions in supramolecular dye nanotubes" (PDF). Nature Chemistry. 4 (8): 655–662. Bibcode:2012NatCh...4..655E. doi:10.1038/nchem.1380. PMID   22824898. S2CID   878082.
  29. ↑ Sengupta S, Ebeling D, Patwardhan S, Zhang X, von Berlepsch H, Böttcher C, et al. (June 2012). "Biosupramolecular nanowires from chlorophyll dyes with exceptional charge-transport properties". Angewandte Chemie. 51 (26): 6378–6382. doi:10.1002/anie.201201961. PMID   22644905.
  30. ↑ Shi X, Zhang X, Ni XL, Zhang H, Wei P, Liu J, et al. (November 2019). "Supramolecular Polymerization with Dynamic Self-Sorting Sequence Control 0". Macromolecules. 52 (22): 8814–8825. Bibcode:2019MaMol..52.8814S. doi:10.1021/acs.macromol.9b02010. S2CID   209711431.
  31. ↑ Qian H, Guo DS, Liu Y (April 2012). "Cucurbituril-modulated supramolecular assemblies: from cyclic oligomers to linear polymers". Chemistry: A European Journal. 18 (16): 5087–5095. doi:10.1002/chem.201101904. PMID   22407677.
  32. ↑ Pappalardo S, Villari V, Slovak S, Cohen Y, Gattuso G, Notti A, et al. (2007-10-05). "Counterion-dependent proton-driven self-assembly of linear supramolecular oligomers based on amino-calix[5]arene building blocks". Chemistry: A European Journal. 13 (29): 8164–8173. doi:10.1002/chem.200601785. PMID   17639537.
  33. ↑ Deng W, Yamaguchi H, Takashima Y, Harada A (2007-07-02). "A chemical-responsive supramolecular hydrogel from modified cyclodextrins". Angewandte Chemie. 46 (27): 5144–5147. doi:10.1002/anie.200701272. PMID   17526038.
  34. ↑ Wang F, Han C, He C, Zhou Q, Zhang J, Wang C, et al. (August 2008). "Self-sorting organization of two heteroditopic monomers to supramolecular alternating copolymers". Journal of the American Chemical Society. 130 (34): 11254–11255. doi:10.1021/ja8035465. PMID   18680368.
  35. ↑ Hirao T, Kudo H, Amimoto T, Haino T (September 2017). "Sequence-controlled supramolecular terpolymerization directed by specific molecular recognitions". Nature Communications. 8 (1): 634. Bibcode:2017NatCo...8..634H. doi: 10.1038/s41467-017-00683-5 . PMC   5608752 . PMID   28935856.
  36. ↑ Yashima E, Ousaka N, Taura D, Shimomura K, Ikai T, Maeda K (November 2016). "Supramolecular Helical Systems: Helical Assemblies of Small Molecules, Foldamers, and Polymers with Chiral Amplification and Their Functions". Chemical Reviews. 116 (22): 13752–13990. doi: 10.1021/acs.chemrev.6b00354 . PMID   27754649.
  37. ↑ van Gestel J, Palmans AR, Titulaer B, Vekemans JA, Meijer EW (April 2005). ""Majority-rules" operative in chiral columnar stacks of C3-symmetrical molecules". Journal of the American Chemical Society. 127 (15): 5490–5494. doi:10.1021/ja0501666. PMID   15826186.
  38. ↑ Shen Z, Sang Y, Wang T, Jiang J, Meng Y, Jiang Y, et al. (September 2019). "Asymmetric catalysis mediated by a mirror symmetry-broken helical nanoribbon". Nature Communications. 10 (1): 3976. Bibcode:2019NatCo..10.3976S. doi: 10.1038/s41467-019-11840-3 . PMC   6726595 . PMID   31484928.
  39. ↑ Adelizzi B, Van Zee NJ, de Windt LN, Palmans AR, Meijer EW (April 2019). "Future of Supramolecular Copolymers Unveiled by Reflecting on Covalent Copolymerization" (PDF). Journal of the American Chemical Society. 141 (15): 6110–6121. doi: 10.1021/jacs.9b01089 . PMID   30889358.
  40. ↑ Van Zee NJ, Adelizzi B, Mabesoone MF, Meng X, Aloi A, Zha RH, et al. (June 2018). "Potential enthalpic energy of water in oils exploited to control supramolecular structure". Nature. 558 (7708): 100–103. Bibcode:2018Natur.558..100V. doi:10.1038/s41586-018-0169-0. PMID   29849144. S2CID   44075506.
  41. ↑ Herbst F, Döhler D, Michael P, Binder WH (February 2013). "Self-healing polymers via supramolecular forces". Macromolecular Rapid Communications. 34 (3): 203–220. doi:10.1002/marc.201200675. PMID   23315930.
  42. ↑ Cordier P, Tournilhac F, Soulié-Ziakovic C, Leibler L (February 2008). "Self-healing and thermoreversible rubber from supramolecular assembly". Nature. 451 (7181): 977–980. Bibcode:2008Natur.451..977C. doi:10.1038/nature06669. PMID   18288191. S2CID   205212362.
  43. ↑ Yanagisawa Y, Nan Y, Okuro K, Aida T (January 2018). "Mechanically robust, readily repairable polymers via tailored noncovalent cross-linking". Science. 359 (6371): 72–76. Bibcode:2018Sci...359...72Y. doi: 10.1126/science.aam7588 . PMID   29242235.
  44. ↑ Herbst F, Seiffert S, Binder WH (2012). "Dynamic supramolecular poly(isobutylene)s for self-healing materials". Polymer Chemistry. 3 (11): 3084–3092. doi:10.1039/C2PY20265D.
  45. ↑ Holten-Andersen N, Harrington MJ, Birkedal H, Lee BP, Messersmith PB, Lee KY, Waite JH (February 2011). "pH-induced metal-ligand cross-links inspired by mussel yield self-healing polymer networks with near-covalent elastic moduli". Proceedings of the National Academy of Sciences of the United States of America. 108 (7): 2651–2655. Bibcode:2011PNAS..108.2651H. doi: 10.1073/pnas.1015862108 . PMC   3041094 . PMID   21278337.
  46. ↑ Burattini S, Colquhoun HM, Fox JD, Friedmann D, Greenland BW, Harris PJ, et al. (November 2009). "A self-repairing, supramolecular polymer system: healability as a consequence of donor-acceptor pi-pi stacking interactions". Chemical Communications. 44 (44): 6717–6719. doi:10.1039/B910648K. PMID   19885456.
  47. ↑ Peurifoy SR, Guzman CX, Braunschweig AB (2015). "Topology, assembly, and electronics: three pillars for designing supramolecular polymers with emergent optoelectronic behavior". Polymer Chemistry. 6 (31): 5529–5539. doi:10.1039/C5PY00420A.
  48. ↑ Watson JD, Crick FH (April 1953). "Molecular structure of nucleic acids; a structure for deoxyribose nucleic acid". Nature. 171 (4356): 737–738. Bibcode:1953Natur.171..737W. doi:10.1038/171737a0. PMID   13054692. S2CID   4253007.
  49. ↑ Pauling L, Corey RB, Branson HR (April 1951). "The structure of proteins; two hydrogen-bonded helical configurations of the polypeptide chain". Proceedings of the National Academy of Sciences of the United States of America. 37 (4): 205–211. Bibcode:1951PNAS...37..205P. doi: 10.1073/pnas.37.4.205 . PMC   1063337 . PMID   14816373.
  50. 1 2 3 4 5 Dong R, Zhou Y, Huang X, Zhu X, Lu Y, Shen J (January 2015). "Functional supramolecular polymers for biomedical applications". Advanced Materials. 27 (3): 498–526. doi:10.1002/adma.201402975. PMID   25393728. S2CID   205257015.
  51. ↑ Lim YB, Moon KS, Lee M (April 2009). "Recent advances in functional supramolecular nanostructures assembled from bioactive building blocks". Chemical Society Reviews. 38 (4): 925–934. doi:10.1039/b809741k. PMID   19421572.
  52. ↑ Petkau-Milroy K, Brunsveld L (January 2013). "Supramolecular chemical biology; bioactive synthetic self-assemblies". Organic & Biomolecular Chemistry. 11 (2): 219–232. doi:10.1039/C2OB26790J. PMID   23160566.
  53. ↑ Li J, Li X, Ni X, Wang X, Li H, Leong KW (August 2006). "Self-assembled supramolecular hydrogels formed by biodegradable PEO-PHB-PEO triblock copolymers and alpha-cyclodextrin for controlled drug delivery". Biomaterials. 27 (22): 4132–4140. doi:10.1016/j.biomaterials.2006.03.025. PMID   16584769.
  54. ↑ Appel EA, del Barrio J, Loh XJ, Scherman OA (September 2012). "Supramolecular polymeric hydrogels". Chemical Society Reviews. 41 (18): 6195–6214. doi:10.1039/c2cs35264h. PMID   22890548.
  55. ↑ Yan X, Wang F, Zheng B, Huang F (September 2012). "Stimuli-responsive supramolecular polymeric materials". Chemical Society Reviews. 41 (18): 6042–6065. doi:10.1039/c2cs35091b. PMID   22618080.
  56. ↑ Ma X, Tian H (July 2014). "Stimuli-responsive supramolecular polymers in aqueous solution". Accounts of Chemical Research. 47 (7): 1971–1981. doi:10.1021/ar500033n. PMID   24669851.
  57. ↑ Dong R, Su Y, Yu S, Zhou Y, Lu Y, Zhu X (October 2013). "A redox-responsive cationic supramolecular polymer constructed from small molecules as a promising gene vector". Chemical Communications. 49 (84): 9845–9847. doi:10.1039/C3CC46123H. PMID   24030731.
  58. ↑ Seiffert S, Sprakel J (January 2012). "Physical chemistry of supramolecular polymer networks". Chemical Society Reviews. 41 (2): 909–930. doi:10.1039/c1cs15191f. PMID   21909565.
  59. ↑ Huang Z, Chen X, Wu G, Metrangolo P, Whitaker D, McCune JA, Scherman OA (April 2020). "Host-Enhanced Phenyl-Perfluorophenyl Polar-π Interactions". Journal of the American Chemical Society. 142 (16): 7356–7361. doi:10.1021/jacs.0c02275. PMC   7181256 . PMID   32248683.
  60. ↑ Huang Z, Chen X, O'Neill SJ, Wu G, Whitaker DJ, Li J, et al. (January 2022). "Highly compressible glass-like supramolecular polymer networks". Nature Materials. 21 (1): 103–109. Bibcode:2022NatMa..21..103H. doi:10.1038/s41563-021-01124-x. PMID   34819661. S2CID   244532641.
  61. ↑ Hartgerink JD, Beniash E, Stupp SI (November 2001). "Self-assembly and mineralization of peptide-amphiphile nanofibers" . Science. 294 (5547): 1684–1688. Bibcode:2001Sci...294.1684H. doi:10.1126/science.1063187. PMID   11721046. S2CID   19210828.
  62. ↑ Lu HD, Charati MB, Kim IL, Burdick JA (March 2012). "Injectable shear-thinning hydrogels engineered with a self-assembling Dock-and-Lock mechanism". Biomaterials. 33 (7): 2145–2153. doi:10.1016/j.biomaterials.2011.11.076. PMID   22177842.
  63. ↑ Kameta N, Masuda M, Mizuno G, Morii N, Shimizu T (May 2008). "Supramolecular nanotube endo sensing for a guest protein". Small. 4 (5): 561–565. doi:10.1002/smll.200700710. PMID   18384039.
  64. ↑ Kameta N, Yoshida K, Masuda M, Shimizu T (2009). "Supramolecular Nanotube Hydrogels: Remarkable Resistance Effect of Confined Proteins to Denaturants". Chemistry of Materials. 21 (24): 5892–5898. doi:10.1021/cm903108h.
  65. ↑ Janib SM, Moses AS, MacKay JA (August 2010). "Imaging and drug delivery using theranostic nanoparticles". Advanced Drug Delivery Reviews. 62 (11): 1052–1063. doi:10.1016/j.addr.2010.08.004. PMC   3769170 . PMID   20709124.
  66. ↑ Barreto JA, O'Malley W, Kubeil M, Graham B, Stephan H, Spiccia L (March 2011). "Nanomaterials: applications in cancer imaging and therapy". Advanced Materials. 23 (12): H18–H40. doi:10.1002/adma.201100140. PMID   21433100. S2CID   205239939.
  67. ↑ Shah RN, Shah NA, Del Rosario Lim MM, Hsieh C, Nuber G, Stupp SI (February 2010). "Supramolecular design of self-assembling nanofibers for cartilage regeneration". Proceedings of the National Academy of Sciences of the United States of America. 107 (8): 3293–3298. doi: 10.1073/pnas.0906501107 . PMC   2840471 . PMID   20133666.
  68. ↑ Dankers PY, Harmsen MC, Brouwer LA, van Luyn MJ, Meijer EW (July 2005). "A modular and supramolecular approach to bioactive scaffolds for tissue engineering". Nature Materials. 4 (7): 568–574. Bibcode:2005NatMa...4..568D. doi:10.1038/nmat1418. PMID   15965478. S2CID   17464761.
  69. ↑ Buchberger A, Simmons CR, Fahmi NE, Freeman R, Stephanopoulos N (January 2020). "Hierarchical Assembly of Nucleic Acid/Coiled-Coil Peptide Nanostructures". Journal of the American Chemical Society. 142 (3): 1406–1416. doi: 10.1021/jacs.9b11158 . PMID   31820959.
  70. ↑ Biswas S, Kinbara K, Oya N, Ishii N, Taguchi H, Aida T (June 2009). "A tubular biocontainer: metal ion-induced 1D assembly of a molecularly engineered chaperonin". Journal of the American Chemical Society. 131 (22): 7556–7557. doi:10.1021/ja902696q. PMID   19489642.
  71. ↑ Kato T, Kondo G, Hanabusa K (March 1998). "Thermoreversible Self-Organized Gels of a Liquid Crystal Formed by Aggregation of trans-1,2-Bis(acylamino)cyclohexane Containing a Mesogenic Moiety". Chemistry Letters. 27 (3): 193–194. doi:10.1246/cl.1998.193. ISSN   0366-7022.
  72. ↑ Yano K, Itoh Y, Araoka F, Watanabe G, Hikima T, Aida T (January 2019). "Nematic-to-columnar mesophase transition by in situ supramolecular polymerization". Science. 363 (6423): 161–165. Bibcode:2019Sci...363..161Y. doi: 10.1126/science.aan1019 . PMID   30630928.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.