title: Novel intestinal-targeted Ca-alginate-based carrier for pH-responsive protection and release of lactic acid bacteria.
abstract: A novel intestinal-targeted carrier for pH-responsive protection of lactic acid bacteria in stomach and rapid release of lactic acid bacteria in small intestine is successfully developed. The proposed carrier is composed of a Ca-alginate/protamine (CAP) composite shell and a Lactobacillus-casei-encapsulated Ca-alginate (CA) core. The carriers are prepared simply by a coextrusion minifluidic and subsequent adsorption method. The CAP composite shell offers not only improved protection for Lactobacillus casei to guarantee the endurance and survival in the stomach but also satisfactory intestinal-targeted characteristics to guarantee the rapid release of Lactobacillus casei in the small intestine. In the stomach, where there is an acidic environment, the diffusion channels delineated by the CA networks in the CAP composite shell of the carriers are choked with protamine molecules; as a result, it is hard for the gastric acid to diffuse across the CAP composite shell and thus the encapsulated Lactobacillus casei inside carriers can be efficiently protected. However, when they come to the small intestine, where there is a neutral environment, the carriers dissolve rapidly because of the cooperation between protamine and trypsin; consequently, the encapsulated Lactobacillus casei can be quickly released. The proposed CAP composite carrier provides a novel mode for developing efficient protection systems, responsive controlled-release systems, and intestinal-targeted drug delivery systems.
authors.affiliation: School of Chemical Engineering, §School of Light Industry, Textile and Food Engineering, and ⊥State Key Laboratory of Polymer Materials Engineering, and Collaborative Innovation Center for Biomaterials Science and Technology, Sichuan University , Chengdu, Sichuan 610065, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Mei
authors.forename: Fan
authors.initials: F
authors.lastname: He
authors.forename: Rong-Qing
authors.initials: RQ
authors.lastname: Zhou
authors.forename: Chong-De
authors.initials: CD
authors.lastname: Wu
authors.forename: Ru
authors.initials: R
authors.lastname: Liang
authors.forename: Rui
authors.initials: R
authors.lastname: Xie
authors.forename: Xiao-Jie
authors.initials: XJ
authors.lastname: Ju
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Liang-Yin
authors.initials: LY
authors.lastname: Chu
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D002118:Calcium / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry* / Q000378:metabolism; D016503:Drug Delivery Systems / Q000295:instrumentation / Q000379:methods*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007422:Intestines / Q000382:microbiology*; D019344:Lactic Acid / Q000378:metabolism; D007780:Lacticaseibacillus casei / Q000737:chemistry* / Q000378:metabolism; D051379:Mice; D019936:Probiotics / Q000008:administration & dosage / Q000737:chemistry*
chemical_list: D000464:Alginates; D004337:Drug Carriers; D006603:Hexuronic Acids; D019344:Lactic Acid; D020723:Glucuronic Acid; D002118:Calcium