Nano- drugs enhance the bioavailability through the improvement of dissolution rate and saturation solubility of drugs, by virtue of their small sizes. Besides enhancing the solubilization of compounds in water, they are known to exhibit influences on surfactant aggregation leading to micelle formation, phase manifestation of multicomponent systems with reference to nanodispersions and conductance percolation, clouding of surfactants and polymers, and so forth [57]. The basic advantage of precipitation technique is the use of simple and low cost equipments; but the challenge is the addition of the growing drug crystals to avoid formation of microparticles. Hence, its appropriate analysis and optimization is necessary to enhance the drug’s pharmacokinetic and therapeutic effects. Date, and R. M. Kulkarni, “Nanosuspensions: a promising drug delivery strategy,”, R. H. Muller, B. H. L. Bohm, and J. Grau, “Nanosuspensions: a formulation approach for poorly soluble and poorly bioavailable drugs,” in, E. Merisko-Liversidge, G. G. Liversidge, and E. R. Cooper, “Nanosizing: a formulation approach for poorly-water-soluble compounds,”, G. G. Liversidge and P. Conzentino, “Drug particle size reduction for decreasing gastric irritancy and enhancing absorption of naproxen in rats,”, C. M. Keck and R. H. Müller, “Drug nanocrystals of poorly soluble drugs produced by high pressure homogenisation,”, P. Langguth, A. Hanafy, D. Frenzel et al., “Nanosuspension formulations for low-soluble drugs: pharmacokinetic evaluation using spironolactone as model compound,”, C. Jacobs and R. H. Müller, “Production and characterization of a budesonide nanosuspension for pulmonary administration,”, J. Möschwitzer, G. Achleitner, H. Pomper, and R. H. Müller, “Development of an intravenously injectable chemically stable aqueous omeprazole formulation using nanosuspension technology,”, G. Sunkara and U. Micronization is another conventional technique for the particle size reduction. The volume estimate of 250 mL is derived from typical bioequivalence study protocols that prescribe administration of a drug product to fasting human volunteers with a glass of water [9]. Hydrotropes with cationic hydrophilic group are rare, for example salts of aromatic amines, such as procaine hydrochloride. Surfactant also improves wetting of solids and increases the rate of disintegration of solid into finer particles [11]. It is well-known that the addition of an organic cosolvent to water can dramatically change the solubility of drugs[80-81]. A third benefit to increased drug solubility is the choice of solvent systems. 3721725, 1973. I. R. Buxton and J. M. Peach, “Process and apparatus for freezing a liquid medium,” US Patent no. Micronized fenofibrate exhibited more than 10-fold (1.3% to 20%) increase in dissolution in at 30 minutes biorelevant media [16, 17]. The particle size distribution of the solid particles in nanosuspensions is usually less than one micron with an average particle size ranging between 200 and 600 nm [25, 26]. Polar solvents dissolve polar solutes, … The term insoluble is often applied to poorly or very poorly soluble compounds [2]. Cryogenic techniques have been developed to enhance the dissolution rate of drugs by creating nanostructured amorphous drug particles with high degree of porosity at very low-temperature conditions. 4 0 obj High-shear forces resulting in high local temperature in the extruder is a problem for heat sensitive materials. Erythromycin dihydrate was found to exhibit significant differences in the dissolution rate when compared to monohydrate and anhydrate forms [63]. This system restricts the prediction using the parameters solubility and intestinal permeability. Hot-melt extrusion is essentially the same as the fusion method except that intense mixing of the components is induced by the extruder. Nanosuspension technology has been developed as a promising candidate for efficient delivery of hydrophobic drugs. For example, zinc is insoluble in hydrochloric acid, but does dissolve in it by chemically reacting into zinc chloride and hydrogen, where zinc chloride is soluble in hydrochloric acid. The improvement of drug solubility thereby its oral bio-availability remains one of the most challenging aspects of drug development process especially for oral-drug delivery system. A classic example of the importance of polymorphism on bioavailability is that of chloramphenicol palmitate suspensions. There are numerous approaches available and reported in literature to enhance the solubility of poorly water-soluble drugs. It is commonly expressed as a concentration, either by mass (g of solute per kg of solvent, g per dL (100 mL) of solvent), molarity, molality, mole fraction, or other similar descriptions of concentration. Solubility enhancement of poorly solubility drugs is a challange and many drugs are affected to their bioavailability. In this article, physicochemical principles of salt solubility are presented, with special reference to the influence of pH-solubility profiles of acidic and basic drugs on salt formation and dissolution. endobj It is a prodrug of tenofovir and can be rapidly metabolized to tenofovir. The cavitations forces within the particles are sufficiently high to convert the drug microparticles into nanoparticles. 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