Double emulsion technique

Figure 16.2 Preparation of starch acetate microparticles by water-in-oil-in-water double emulsion technique.

Meng FT, Ma GH, Qiu W, Su ZG. W/O/W double emulsion technique using ethyl acetate as organic solvent effects of its diffusion rate on the characteristics of microparticles. J Control Release 2003 91(3) 407-416. 

Boyadzhiev L and Bezenshek E. Carrier mediated extraction Application of double emulsion technique for mercury removal from waste water. J Membr Sci 1983 14 13-18. 

Upon addition of proteins to aprotic, hydrophobic solvents, the increased intramolecular interactions of the lyophilized protein result in restricted conformational mobility of the protein, thus restricting activity [30], However, proteins display increased thermostability in anhydrous organic solvents as a result of the reduced conformational mobility [31], and water-free methods may help avoid aggregation processes that occur when using the double-emulsion technique, in which the protein is conformationally mobile. 

In particle production by solvent evaporation, the dmg and polymers are dissolved (solvation) in one organic solvent phase that is not miscible with water. The drug-loaded polymer solution is dispersed in a water phase, yielding an oil in water (O/W) emulsion. The organic solvent partitions into the aqueous phase from which it is removed by evaporation [73]. Usually, double-emulsion techniques are used to prepare the microcapsules. Water/oil/water (W/O/W) or oil/oil/water (0/0/W) systems are prepared by dissolving or dispersing the compound in an aqueous or lipid me-... 

Fig. 1.5 Preparation of microcapsules with a double emulsion technique. A primary water-in-oil (W/O) emulsion (step 1) serves as the oil phase for secondary emulsification step with a water phase...

Double stranded RNA, see dsRNA Double emulsion technique... 

Dinarvand R, Moghadam SH, Sheikhi A, Atyabi F. Effect of surfactant HLB and different formnlation variables on the properties of poly-D,L-lactide microspheres of naltrexone prepared by double emulsion technique. Journal of Microencapsulation. March 2005 22(2) 139-151. PubMed PMID 16019900. 

Tapan Kumar G., Chhatrapal C., Ajazuddin, Amit A., Hemant B., and Dulal Krishna T. Prospects of pharmaceuticals and biopharmaceuticals loaded microparticles prepared by double emulsion technique for controlled delivery. Saudi Pharm. J. 21(2) (2013) 125-141. 

The polymers represented by 6 have been used to incorporate proteins of different molecular sizes into microspheres by a double-emulsion technique (Tabata et al, 1993b). The proteins—lysozyme, trypsin, heparinase, ovalbumin, BSA, and immunoglobulin—were primarily incorporated into a 25 75 fatty acid/sebacic acid copolymer at a loading of 2 wt%. The microspheres produced by this method were spherical, irrespective of the... 

Particle formulations can be also used for sustained gene delivery (Fig. 3.10). In several studies, plasmid DNA was loaded into biodegradable particles by using a double emulsion technique (Akiyama et al, 2010 Kang et al.,200B). 

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