Chitosan-alginate microcapsules for oral delivery of egg yolk immunoglobulin (IgY): effects of chitosan concentration.
In our previous study, chitosan-alginate microcapsules were developed to protect egg yolk immunoglobulin (IgY) from gastric inactivation. The present study was undertaken to determine the effect of chitosan concentration (0-0.8%; w/v) on various properties of the microcapsules in order to produce the optimum chitosan-alginate microcapsules for use in the oral delivery of IgY. The properties investigated included microcapsule morphology, loading capacity for IgY (expressed as the IgY loading percentage, w/w, of microcapsules), encapsulation efficiency (EE%), in vitro gastroresistance, and IgY release. IgY loading percentage and EE% were both highest at 0.2% (w/v) chitosan, and, above this level, further increases were not observed. The stability of IgY in simulated gastric fluid (pH 1.2) was significantly improved by encapsulation in alginate microcapsules (IgY retained 43.5% of its activity) and was further improved by including chitosan at any of the chitosan concentrations assessed (IgY retained an average of 69.4% activity) although there was no difference in protection of gastric inactivation among concentrations of chitosan varying from 0.05% to 0.8% (w/v). Higher chitosan concentrations (i.e., >/=0.2%; w/v) prolonged the release of IgY from the microcapsules during simulated intestinal fluid incubation (pH 6.8). However, above the 0.2% (w/v) level, no significant differences were observed. We conclude that the optimum chitosan concentration for microencapsulation is 0.2% (w/v).
Department of Bioscience and Biotechnology, Dalian University of Technology, No. 2 Linggong Road, Dalian, China.
Xiao-Yu
XY
Li
Li-Ji
LJ
Jin
Ya-Nan
YN
Lu
Yu-Hong
YH
Zhen
Shu-Ying
SY
Li
Lin-Hui
LH
Wang
Yong-Ping
YP
Xu
D000284:Administration, Oral; D000464:Alginates / Q000737:chemistry*; D000818:Animals; D002214:Capsules / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D004530:Egg Yolk / Q000378:metabolism*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007136:Immunoglobulins / Q000378:metabolism; D008855:Microscopy, Electron, Scanning
D000464:Alginates; D002214:Capsules; D004337:Drug Carriers; D006603:Hexuronic Acids; C016512:IgY; D007136:Immunoglobulins; D020723:Glucuronic Acid; D048271:Chitosan