Emulsions encapsulation

Control of the particle size while retaining precise control over the release rate is enabled by compartmentalization of the sol-gel solution into droplets of definite size. This can be achieved by emulsification of the sol-gel solution by mixing it with a solution composed of a surfactant and a non-polar solvent (Figure 2.13). When an active molecule is located in the aqueous droplet of a W/O emulsion, encapsulation occurs as the silicon precursors polymerize to build an oxide cage around the active species. By changing the solvent-surfactant combination, the particle size can be varied from 10 nm to 100 pm as the size of the particles is controlled by the size of the emulsion droplet, which acts as a nano-reactor for the sol-gel reaction (Figure 2.13). 

Forty-five hundred pound batches, each, of modified Compn A-3 using the three different waxes were prepd. It is significant that the method used in their production was by an emulsion encapsulation technique. As part of this program, 400 each 105mm HEP-T M393 rounds were loaded and ballistically tested against standard Compn A-3. As a result, Compn A-3 made using AC-656 polyethylene was selected for further evaluation. All acceptance and safety certification tests were successfully completed. It is concluded from the evaluation of the materials produced that ... 

The emulsion encapsulation system is superior to the present production technique(hot water slurry technique). 

The most recent method of coating RDX is with the emulsion encapsulation technique (Refs 103, 104, 109 111). The process involves essentially the following steps ... 

The method described in Ref 109 for the emulsion encapsulation process is about the same as that described above. Sulfuric acid is used to break the polyethylene wax emulsion. In addition, 0.05% methyl p-hydroxbenzoate is used in the final wash to prevent mold growth... 

Aizpurua et al. [96] have studied the kinetics of vinyl acetate miniemulsions stabilized with PS or PVAc. Guyot and coworkers [97] used PS as the costabilizer for the mini emulsion encapsulation of pigment. Samer [67] has used PMMA to stabilize MMA miniemulsions for continuous polymerization in a CSTR. 

Klinkesorn U, Sophanodora P, Chinachoti P et al. (2005) Stability of spray-dried tuna oil emulsions encapsulated with two-layered interfacial membranes. Journal of Agricultural and Food Chemistry 53 8365-8371. 

Grigoriev DO, Bukreeva T, Mohwald H, Shchukin DG. New method for fabrication of loaded micro- and nanocontainers emulsion encapsulation by polyelectrolyte layer-by-layer deposition on the liquid core. Langmuir 2008 24(3) 999—1004. 

Carrier material is a blend of CA and MD, flavor is D-limonene. Feed emulsion, Emulsion after atomization, < Reconstitute emulsion encapsulated in spray-dried powder. 

Sediment stabilization in fruit juices, obtaining body in beverage powders Stabilization of powdery tiroma emulsions, encapsulation of aroma substances... 

The survival times of the rats after i.v. administration of the emulsions are shown in Figure 11.7. The survival time of the rat administered the W/O/W emulsion is longer than that of the rat with the O/W emulsion. The rats administered the O/W emulsion (>1.5ml/kg) died within two days. Dyspnea was observed in these rats after administration of the O/W emulsion. The rats administered W/O/W emulsion encapsulating drug (>2.0ml/kg) died between seven and nine days. Diarrhea, bloody stool, and anemia were observed in these rats at four to five days after administration. 

The acute toxicity and deposition in liver of the hpiodol W/O/W emulsion encapsulating anticancer agent after hepatic arterial administration to rats were investigated and compared to the O/W emulsion used conventionally for TAB therapy (Hino et al., 1999). 

Hino T, T akeuchi H, Niwa T, Nagaya K, Kawashima Y, Nakano S, Yamazaki F, Kumada T. 1995. Formulation of W/O/W emulsion encapsulating epirubicin hydrochloride for the transcatheter arterial embolization therapy for heparocellular carcinoma. Drug Deliv Sys 10 115-119. 

Grigoriev D. O., Bukreeva T, Mohwald H. and Shchukin D. G. (2008), New Method for Fabrication of Loaded Micro- and Nanocontainers Emulsion Encapsulation by Polyelectrolyte Layer-by-Layer Deposition on the Liquid Core , Langmuir, 24,999-1004. 

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