Micromeritics

Last updated

Micromeritics is the science and technology of small particles pioneered by Joseph M. DallaValle. [1] It is thus the study of the fundamental and derived properties of individual as well as a collection of particles. The knowledge and control of the size of particles has importance in pharmacy and materials science. The size, and hence the surface area of a particle, can be related to the physical, chemical and pharmacological properties of drugs. Clinically, the particle size of a drug can affect its release from dosage forms that are administered orally, parenterally, rectally and topically. The successful formulation of suspensions, emulsions and tablets; both physical stability and pharmacological response also depends on the particle size achieved in the product. [2] [3] [4] [5]

Contents

Origin

The term was coined by Joseph Marius DallaValle in his book Micromeritics: The Technology of Fine Particles (1948). [1] It was derived from the Greek words Greek : μικρο, romanized: micro meaning "small" and Greek : μέρος, romanized: méros meaning "part". [6] The size range which he covered in the book was from 10−1 to 105 micrometers. Anything smaller than this but bigger than a molecule was referred to at the time as a colloid but is now often referred to as a nanoparticle. Applications included soil physics, mineral physics, chemical engineering, geology, and hydrology. Characteristics discussed included particle size and shape, packing, electrical, optical, chemical and surface science.

Applications

Release and dissolution

Particle size and surface area influence the release of a drug from a dosage form that is administered orally, rectally, parenterally, and topically. Higher surface area brings about intimate contact of the drug with the dissolution fluids in vivo and increases the drug solubility and dissolution.

Absorption and drug action

Particle size and surface area influence the drug absorption and subsequently the therapeutic action. The higher the dissolution, the faster the absorption and hence the quicker and greater the drug action.

Physical stability

Micromeritic properties of a particle, i.e. the particle size in a formulation, influence the physical stability of the suspensions and emulsions. The smaller the size of the particle, the better the physical stability of the dosage form owing to the Brownian motion of the particles in the dispersion.

Dose uniformity

Good flow properties of granules and powders are important in the manufacturing of tablets and capsules. The distribution of particles should be uniform in terms of number and weight. Very small particle size causes attraction, which in turn destabilises the suspension by coagulating.

See also

Related Research Articles

An emulsion is a mixture of two or more liquids that are normally immiscible owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid is dispersed in the other. Examples of emulsions include vinaigrettes, homogenized milk, liquid biomolecular condensates, and some cutting fluids for metal working.

<span class="mw-page-title-main">Route of administration</span> Path by which a drug, fluid, poison, or other substance is taken into the body

In pharmacology and toxicology, a route of administration is the way by which a drug, fluid, poison, or other substance is taken into the body.

<span class="mw-page-title-main">Topical medication</span> Medication applied to body surfaces

A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes including creams, foams, gels, lotions, and ointments. Many topical medications are epicutaneous, meaning that they are applied directly to the skin. Topical medications may also be inhalational, such as asthma medications, or applied to the surface of tissues other than the skin, such as eye drops applied to the conjunctiva, or ear drops placed in the ear, or medications applied to the surface of a tooth. The word topical derives from Greek τοπικόςtopikos, "of a place".

<span class="mw-page-title-main">Nanoparticle</span> Particle with size less than 100 nm

A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead.

Microencapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules, with useful properties. In general, it is used to incorporate food ingredients, enzymes, cells or other materials on a micro metric scale. Microencapsulation can also be used to enclose solids, liquids, or gases inside a micrometric wall made of hard or soft soluble film, in order to reduce dosing frequency and prevent the degradation of pharmaceuticals.

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

Enteral administration is food or drug administration via the human gastrointestinal tract. This contrasts with parenteral nutrition or drug administration, which occurs from routes outside the GI tract, such as intravenous routes. Enteral administration involves the esophagus, stomach, and small and large intestines. Methods of administration include oral, sublingual, and rectal. Parenteral administration is via a peripheral or central vein. In pharmacology, the route of drug administration is important because it affects drug metabolism, drug clearance, and thus dosage. The term is from Greek enteros 'intestine'.

Absorption is the journey of a drug travelling from the site of administration to the site of action.

<span class="mw-page-title-main">Miniemulsion</span> Particular type of emulsion

A miniemulsion is a particular type of emulsion. A miniemulsion is obtained by ultrasonicating a mixture comprising two immiscible liquid phases, one or more surfactants and, possibly, one or more co-surfactants. They usually have nanodroplets with uniform size distribution (20–500 nm) and are also known as sub-micron, mini-, and ultra-fine grain emulsions.

Dosage forms are pharmaceutical drug products presented in a specific form for use. They contain a mixture of active ingredients and inactive components (excipients), configured in a particular way and apportioned into a specific dose. For example, two products may both be amoxicillin, but one may come in 500 mg capsules, while another may be in 250 mg chewable tablets.

Pharmaceutical formulation, in pharmaceutics, is the process in which different chemical substances, including the active drug, are combined to produce a final medicinal product. The word formulation is often used in a way that includes dosage form.

<span class="mw-page-title-main">Solid lipid nanoparticle</span> Novel drug delivery system

Lipid nanoparticles (LNPs) are very small spherical particles composed of lipids. They are a novel pharmaceutical drug delivery system, and a novel pharmaceutical formulation. Using LNPs for drug delivery was first approved in 2018 for the siRNA drug Onpattro. LNPs became more widely known in late 2020, as some COVID-19 vaccines that use RNA vaccine technology coat the fragile mRNA strands with PEGylated lipid nanoparticles as their delivery vehicle.

<span class="mw-page-title-main">Nano spray dryer</span>

Nano spray dryers refer to using spray drying to create particles in the nanometer range. Spray drying is a gentle method for producing powders with a defined particle size out of solutions, dispersions, and emulsions which is widely used for pharmaceuticals, food, biotechnology, and other industrial materials synthesis.

<span class="mw-page-title-main">Pharmaceutical manufacturing</span> Synthesis of pharmaceutical drugs

Pharmaceutical manufacturing is the process of industrial-scale synthesis of pharmaceutical drugs as part of the pharmaceutical industry. The process of drug manufacturing can be broken down into a series of unit operations, such as milling, granulation, coating, tablet pressing, and others.

A nanocapsule is a nanoscale shell made from a nontoxic polymer. They are vesicular systems made of a polymeric membrane which encapsulates an inner liquid core at the nanoscale. Nanocapsules have many uses, including promising medical applications for drug delivery, food enhancement, nutraceuticals, and for self-healing materials. The benefits of encapsulation methods are for protection of these substances to protect in the adverse environment, for controlled release, and for precision targeting. Nanocapsules can potentially be used as MRI-guided nanorobots or nanobots, although challenges remain.

<span class="mw-page-title-main">Characterization of nanoparticles</span> Measurement of physical and chemical properties of nanoparticles

The characterization of nanoparticles is a branch of nanometrology that deals with the characterization, or measurement, of the physical and chemical properties of nanoparticles.,. Nanoparticles measure less than 100 nanometers in at least one of their external dimensions, and are often engineered for their unique properties. Nanoparticles are unlike conventional chemicals in that their chemical composition and concentration are not sufficient metrics for a complete description, because they vary in other physical properties such as size, shape, surface properties, crystallinity, and dispersion state.

Nanoparticle drug delivery systems are engineered technologies that use nanoparticles for the targeted delivery and controlled release of therapeutic agents. The modern form of a drug delivery system should minimize side-effects and reduce both dosage and dosage frequency. Recently, nanoparticles have aroused attention due to their potential application for effective drug delivery.

Nanomaterials are materials with a size ranging from 1 to 100 nm in at least one dimension. At the nanoscale, material properties become different. These unique properties can be exploited for a variety of applications, including the use of nanoparticles in skincare and cosmetics products.

<span class="mw-page-title-main">Topical cream formulation</span>

Topical cream formulation is an emulsion semisolid dosage form that is used for skin external application. Most of the topical cream formulations contain more than 20 per cent of water and volatiles and/or less than 50 per cent of hydrocarbons, waxes, or polyethylene glycols as the vehicle for external skin application. In a topical cream formulation, ingredients are dissolved or dispersed in either a water-in-oil (W/O) emulsion or an oil-in-water (O/W) emulsion. The topical cream formulation has a higher content of oily substance than gel, but a lower content of oily ingredient than ointment. Therefore, the viscosity of topical cream formulation lies between gel and ointment. The pharmacological effect of the topical cream formulation is confined to the skin surface or within the skin. Topical cream formulation penetrates through the skin by transcellular route, intercellular route, or trans-appendageal route. Topical cream formulation is used for a wide range of diseases and conditions, including atopic dermatitis (eczema), psoriasis, skin infection, acne, and wart. Excipients found in a topical cream formulation include thickeners, emulsifying agents, preservatives, antioxidants, and buffer agents. Steps required to manufacture a topical cream formulation include excipient dissolution, phase mixing, introduction of active substances, and homogenization of the product mixture.

<span class="mw-page-title-main">Polystyrene (drug delivery)</span> Polystyrene in drug delivery

Polystyrene is a synthetic hydrocarbon polymer that is widely adaptive and can be used for a variety of purposes in drug delivery. These methods include polystyrene microspheres, nanoparticles, and solid foams. In the biomedical engineering field, these methods assist researchers in drug delivery, diagnostics, and imaging strategies.

Topical gels are a topical drug delivery dosage form commonly used in cosmetics and treatments for skin diseases because of their advantages over cream and ointment. They are formed from a mixture of gelator, solvent, active drug, and other excipients, and can be classified into organogels and hydrogels. Drug formulation and preparation methods depend on the properties of the gelators, solvents, drug and excipients used.

References

  1. 1 2 Valle, Joseph Marius Dalla; DallaValle, Joseph Marius (1948). Micromeritics: The Technology of Fine Particles. Pitman Publishing Corporation. ISBN   9780598902719. OCLC   1016195333.
  2. Brittain, H. G. (1995). Physical characterization of pharmaceutical solids. Vol. 08. New York: M. Dekker. pp. 963–73. doi:10.1023/a:1015888520352. ISBN   0-8247-9372-2. PMID   1924166. S2CID   38179603.{{cite book}}: |journal= ignored (help)
  3. Carstensen, Jens Thurø (1993). Pharmaceutical principles of solid dosage forms . Lancaster, Pa: Technomic Pub. p.  211. ISBN   0-87762-955-2.
  4. Martin, Alfred N.; Patrick J Sinko (2006). Martin's physical pharmacy and pharmaceutical sciences: physical chemical and biopharmaceutical principles in the pharmaceutical sciences. Phila: Lippincott Williams and Wilkins. pp. 533–560. ISBN   0-7817-5027-X.
  5. Orr, Clyde; Webb, Paul W. (1997). Analytical methods in fine particle technology. Norcross, Ga: Micromeritics Instrument Corp. ISBN   0-9656783-0-X.
  6. "Definition of MICROMERITICS". www.merriam-webster.com. Retrieved 2023-01-15.