Nanosensors are nanoscale devices that measure physical quantities and convert these to signals that can be detected and analyzed. There are several ways proposed today to make nanosensors;these include top-down lithography,bottom-up assembly,and molecular self-assembly. There are different types of nanosensors in the market and in development for various applications,most notably in defense,environmental,and healthcare industries. These sensors share the same basic workflow:a selective binding of an analyte,signal generation from the interaction of the nanosensor with the bio-element,and processing of the signal into useful metrics.
Colloidal gold is a sol or colloidal suspension of nanoparticles of gold in a fluid,usually water. The colloid is coloured usually either wine red or blue-purple . Due to their optical,electronic,and molecular-recognition properties,gold nanoparticles are the subject of substantial research,with many potential or promised applications in a wide variety of areas,including electron microscopy,electronics,nanotechnology,materials science,and biomedicine.
Nanochemistry is an emerging sub-discipline of the chemical and material sciences that deals with the development of new methods for creating nanoscale materials. The term "nanochemistry" was first used by Ozin in 1992 as 'the uses of chemical synthesis to reproducibly afford nanomaterials from the atom "up",contrary to the nanoengineering and nanophysics approach that operates from the bulk "down"'. Nanochemistry focuses on solid-state chemistry that emphasizes synthesis of building blocks that are dependent on size,surface,shape,and defect properties,rather than the actual production of matter. Atomic and molecular properties mainly deal with the degrees of freedom of atoms in the periodic table. However,nanochemistry introduced other degrees of freedom that controls material's behaviors by transformation into solutions. Nanoscale objects exhibit novel material properties,largely as a consequence of their finite small size. Several chemical modifications on nanometer-scaled structures approve size dependent effects.
See also artificial metalloenzyme.
Layer-by-layer (LbL) deposition is a thin film fabrication technique. The films are formed by depositing alternating layers of oppositely charged materials with wash steps in between. This can be accomplished by using various techniques such as immersion,spin,spray,electromagnetism,or fluidics.
A nanodisc is a synthetic model membrane system which assists in the study of membrane proteins. Nanodiscs are discoidal proteins in which a lipid bilayer is surrounded by molecules that are amphipathic molecules including proteins,peptides,and synthetic polymers. It is composed of a lipid bilayer of phospholipids with the hydrophobic edge screened by two amphipathic proteins. These proteins are called membrane scaffolding proteins (MSP) and align in double belt formation. Nanodiscs are structurally very similar to discoidal high-density lipoproteins (HDL) and the MSPs are modified versions of apolipoprotein A1 (apoA1),the main constituent in HDL. Nanodiscs are useful in the study of membrane proteins because they can solubilise and stabilise membrane proteins and represent a more native environment than liposomes,detergent micelles,bicelles and amphipols.
Magnetolithography (ML) is a photoresist-less and photomaskless lithography method for patterning wafer surfaces. ML based on applying a magnetic field on the substrate using paramagnetic metal masks named "magnetic mask" placed on either topside or backside of the wafer. Magnetic masks are analogous to a photomask in photolithography,in that they define the spatial distribution and shape of the applied magnetic field. The fabrication of the magnetic masks involves the use of conventional photolithography and photoresist however. The second component of the process is ferromagnetic nanoparticles that are assembled over the substrate according to the field induced by the mask which blocks its areas from reach of etchants or depositing materials.
Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. While frequently described as being 'silver' some are composed of a large percentage of silver oxide due to their large ratio of surface to bulk silver atoms. Numerous shapes of nanoparticles can be constructed depending on the application at hand. Commonly used silver nanoparticles are spherical,but diamond,octagonal,and thin sheets are also common.
Within surface science,a quartz crystal microbalance with dissipation monitoring (QCM-D) is a type of quartz crystal microbalance (QCM) based on the ring-down technique. It is used in interfacial acoustic sensing. Its most common application is the determination of a film thickness in a liquid environment. It can be used to investigate further properties of the sample,most notably the layer's softness.
A holographic sensor is a device that comprises a hologram embedded in a smart material that detects certain molecules or metabolites. This detection is usually a chemical interaction that is transduced as a change in one of the properties of the holographic reflection,either refractive index or spacing between the holographic fringes. The specificity of the sensor can be controlled by adding molecules in the polymer film that selectively interacts with the molecules of interest.
Amit Chakrabarti is the former William and Joan Porter Chair in Physics at Kansas State University. He currently serves as the dean of the college of arts and sciences at Kansas State University.
Nanoparticles are classified as having at least one of its dimensions in the range of 1-100 nanometers (nm). The small size of nanoparticles allows them to have unique characteristics which may not be possible on the macro-scale. Self-assembly is the spontaneous organization of smaller subunits to form larger,well-organized patterns. For nanoparticles,this spontaneous assembly is a consequence of interactions between the particles aimed at achieving a thermodynamic equilibrium and reducing the system’s free energy. The thermodynamics definition of self-assembly was introduced by Professor Nicholas A. Kotov. He describes self-assembly as a process where components of the system acquire non-random spatial distribution with respect to each other and the boundaries of the system. This definition allows one to account for mass and energy fluxes taking place in the self-assembly processes.
Štefan Luby is a Slovak physicist and senior research fellow at the Slovak Academy of Sciences (SAS). He is doctor honoris causa of University of Salento,Italy,Slovak University of Technology in Bratislava,University of Constantine the Philosopher in Nitra,Slovakia,and Alexander Dubček University in Trenčín,Slovakia. He occupied positions of the director of the Institute of Physics of SAS for nine years and was the president of the SAS for fourteen years (1995–2009). He was the acting president of the All European Academies and the acting president of the Central European Academy of Sciences and Arts. At present,he is a member of Senate and vice-president of the European Academy of Sciences and Arts with the headquarters in Salzburg. He has chaired the editorial board of the Slovak Encyclopaedia Beliana since 1992.
A chemiresistor is a material that changes its electrical resistance in response to changes in the nearby chemical environment. Chemiresistors are a class of chemical sensors that rely on the direct chemical interaction between the sensing material and the analyte. The sensing material and the analyte can interact by covalent bonding,hydrogen bonding,or molecular recognition. Several different materials have chemiresistor properties:semiconducting metal oxides,some conductive polymers,and nanomaterials like graphene,carbon nanotubes and nanoparticles. Typically these materials are used as partially selective sensors in devices like electronic tongues or electronic noses.
In materials and electric battery research,cobalt oxide nanoparticles usually refers to particles of cobalt(II,III) oxide Co
3O
4 of nanometer size,with various shapes and crystal structures.
A copper nanoparticle is a copper based particle 1 to 100 nm in size. Like many other forms of nanoparticles,a copper nanoparticle can be prepared by natural processes or through chemical synthesis. These nanoparticles are of particular interest due to their historical application as coloring agents and the biomedical as well as the antimicrobial ones.
Niveen M. Khashab is a Lebanese chemist and an associate Professor of chemical Sciences and engineering at King Abdullah University of Science and Technology in Saudi Arabia since 2009. She is a laureate of the 2017 L'Oréal-UNESCO Awards for Women in Science "for her contributions to innovative smart hybrid materials aimed at drug delivery and for developing new techniques to monitor intracellular antioxidant activity." She is also a fellow of the Royal Chemical Society,and a member of the American Chemical Society.
Nanoparticle deposition refers to the process of attaching nanoparticles to solid surfaces called substrates to create coatings of nanoparticles. The coatings can have a monolayer or a multilayer and organized or unorganized structure based on the coating method used. Nanoparticles are typically difficult to deposit due to their physical properties.
Susan M. Kauzlarich is an American chemist and is presently a distinguished professor of chemistry at the University of California,Davis. At UC Davis,Kauzlarich leads a research group focused on the synthesis and characterization of Zintl phases and nanoclusters with applications in the fields of thermoelectric materials,magnetic resonance imaging,energy storage,opto-electronics,and drug delivery. Kauzlarich has published over 250 peer-reviewed publications and has been awarded several patents. In 2009,Kauzlarich received the annual Presidential Award for Excellence in Science,Mathematics and Engineering Mentoring,which is administered by the National Science Foundation to acknowledge faculty members who raise the membership of minorities,women and disabled students in the science and engineering fields. In January 2022 she became Deputy Editor for the scientific journal,Science Advances. She gave the Edward Herbert Boomer Memorial Lecture of the University of Alberta in 2023.
So-Jung Park 박소정(朴昭靜) is a professor of chemistry at Ewha Womans University,Republic of Korea. Her research considers the self-assembly of nanoparticles and functional molecules for biomedical and optoelectronic devices. She serves as Associate Editor of ACS Applied Materials &Interfaces and Nanoscale.
