Anhydrous microencapsulation

Exposure to w/o interfaces Reducing or avoiding denaturation at w/o interfaces by including protective excipients/ employing anhydrous microencapsulation processes. 

In the anhydrous microencapsulation, protein and excipients were suspended/dissolved in PLA/acetonitrile solution and then added to cottonseed oil to form an o/o emulsion with Span 85 as an emulsifier. Petroleum ether was then added to extract the acetonitrile and the microspheres were hardened. The microspheres were then recovered by filtration and dried under vacuum. As shown in Table 5 and Fig. 5, without the pore-forming PEG, only 36% BSA was released from PLA microspheres in 1-month of incubation with a total recovery (released-fall soluble and aggregated residue in polymer after release) of 76%. Blending in 30% of 35 kDa PEG with the PLA eliminated the BSA aggregation in polymer completely, with 82% of encapsulated BSA released in 1 month. The improved BSA stability in PLA/PEG microspheres could be attributed to a less acidic and more hydrophilic microenvironment in the polymer. As seen in Fig. 6, unlike PLGA 50/50, which caused a dramatic pH drop in the release medium after a 4-week incubation (41), a relatively neutral pH was retained in the release medium for both PLA and PLA/PEG microspheres. A slightly lower pH in the release medium incubated with PLA/PEG microspheres relative to that in PLA was also... 

Hardas, N., Danviriyakul, S., Foley, J.L., Nawar, W.W., Chinachoti, P. (2000). Accelerated stability studies of microencapsulated anhydrous milk fat. Lebensmittel-Wissen-schaft und-Technologie, 33, 506-513. 

Young, S. L., Sarda, X., Rosenberg, M. (1993). Microencapsulation properties of whey proteins. 1. Microencapsulation of anhydrous milk fat. Journal of Dairy Science, 76, 2868-2877. 

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