Particle formulation

Particle Size Laser Refractometiy is based upon Mie scattering of particles in a liquid medium. Up until about 1985, the power of computers supplied with laser diffraction instruments was not sufficient to utilize the rigorous solution for homogeneous spherical particles formulated by Gustave Mie in 1908. Laser particle instrument manufacturers therefore used approximations conceived by Fraunhofer. 

Factors known to influence the clearance of drugs from interstitial sites, following extravasation or parenteral interstitial or transepithelial administration, include size and surface characteristics of particles, formulation medium, the composition and pH of the interstitial fluid, and disease within the interstitium. Studies indicate that soluble macromolecules smaller than 30 nm can enter the lymphatic system, whereas particulate materials larger than 50 nm are retained in the interstitial sites and serve as a sustained-release depot. The use of lipids or an oil in a formulation and the presence of a negative surface charge all appear to... 

Warheit, D.B., Brock, W.J., Lee, K.P., Webb, T.R., and Reed, K.L. (2005) Comparative pulmonary toxicity inhalation and instillation studies with different Ti02 particle formulations impact of surface treatments on partide toxicity. Toxicological Sciences, 88 (2), 514-524. 

In many cases it is convenient to start from the free-particle formulation, V = 0, and introduce suitable potential barriers to simulate specific interactions. 

Gota VS, Maru GB, Soni TG, Gandhi TR, Kochar N, Agarwal MG. (2010) Safety and pharmacokinetics of a solid lipid curcumin particle formulation in osteosarcoma patients and healthy volunteers. J Agric Eood Chem 58 2095-2099. 

A mixture of B and AP particles formulates an energetic B-AP pyrolant. A small amount of polymeric material is added to serve as a binder of the B and AP parti-... 

Defoaming agents are in three principal categories, but sometimes are used in combination II) surfactants made soluble. (2) dispersions of hard panicles, and f3) dispersions of soft panicles. The fatty acid-fatty alcohol combination in hydrocarbon oil is an example of a solubilized surfactant defoaming formulation Paraffinic waxes and laity amides may be used in soft-particle formulations. The most common of the hard-particle formulations is silica or a mineral coated with silicone dispersed in a vehicle. A particle size as small as 0.1X2 micrometer may be optimal. 

Saturation segregation involves any excess fine particles with no available binding sites on carrier particles. Formulations with excessive dmg loading act this way in certain circumstances. 

In the absence of any significant body of experimental data for rarefied, hypersonic flows, vehicle design has depended greatly on computational modeling. In this section, we briefly review continuum approaches for computing rarefied gas flows. We then pass on to a more complete description of the methods and models associated with a particle formulation. Hybrid methods that combine continuum and particle methods are reviewed briefly. 

Straub, J.A. Chickering, D.E. Lovely, J.C. Zhang, H. Shah, B. Waud, W.R. Berstein, H. Intravenous hydro-phobic drug dehvery a porius particle formulation of Paclitaxel (AI-850). Pharmaceutical Research 2005, 22 (3), 347-355. 

Preparing particle formulations using the acquired Separex technology. Separex S.A. is a French company known for its supercritical fluid technology for particle engineering. 

Equally important are problems in particle formulation. Particle shape, size, strength, and stability must be considered. Often these features coexist with chemical and difiusional difficulties. ... 

With the exception of particle formulations, catalyst manufacturing follows the same paths already considered in this chapter, except on a larger scale. In the laboratory, it is sufficient to make small batches—a hundred grams or a kilogram at the most. Even quantities this small often pose difficult quality control and manipulation problems. When the development... 

Maa Y F, Prestrelski S J (2000). Biopharmaceutical powders particle formulation and formulation considerations. Curr. Pharm. Biotechnol. 1 283-302. 

With a typical size ranging from nanometric (<100 nm) to submicrometric (<1 pm), biopolymeric particles and nanoparticles, made of proteins or polysaccharides, thanks to their excellent compatibility with foods, are able to efficiently encapsulate, protect and deliver bioactive compounds, forming different structures, such as random coils, sheets, or rods around the bioactive molecules. The most suitable biopolymers for the incorporation into foods include (1) proteins, such as whey proteins, casein, gelatin, soy protein, zein, and (2) polysaccharides, such as starch, cellulose, and other hydrocolloids, with the particle formulation depending on the desired particle functionality (size, morphology, charge, permeability, environmental stability), on end product compatibility and in general in product behavior, as well as on release properties and in body behavior. 

Zhang, X. Z., G. M. Sun, et al. (2004). Temperature sensitive dendrite-shaped PNIPAAm/Dex-AI hybrid hydrogel particles formulation and properties. European Polymer Journal 40(9) 2251-2257. 

To improve solubility, an appropriate particle formulation with fast-dissolving additives might be tried first (see example for NOBS in Ref. 145). Alternatively or additionally, disintegrants may be used. This is described in Ref. 146 for a peroxycarboxylic acid combined with swellable polymers such as carboxymethylcellulose. On the other hand, the primary particle size of the active material prior to granulation could be considered, since smaller particles typically show a shorter dissolution time, and if residues are inevitable, are likely to be less visible. If necessary, combinations of both measures (suitable additives and small particle size) may be employed. Several examples are described for the granulation of a manganese catalyst in Ref. 147. 

Reconstructable polymer surfaces form a toolbox for the rapidly developing field of smart coatings and the structure of the coatings can be programmed in the formation. For instance, the colloidal particles formulated by the emulsion copolymerization of acrylate and fluorinated acrylate monomers can form stratified film morphologies, where the fluorinated phase can be driven to the film/ air or film/substrate interfaces. As a result, static and kinetic coefficients of friction can be controlled at the film/air interface, resulting... 

General Principles of Particle Formulation in Spray Fluidized Beds... 

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