title: An improved pH-responsive carrier based on EDTA-Ca-alginate for oral delivery of Lactobacillus rhamnosus ATCC 53103.
abstract: A pH-responsive carrier based on an ethylenediaminetetraacetic-calcium-alginate (EDTA-Ca-Alg) system was developed by controlling the release of Ca2+. The system remained in the solution state at neutral pH since EDTA completely chelated the Ca2+. In contrast, a hydrogel immediately formed when the pH was below 4.0, which triggered the in situ release of Ca2+from the EDTA-Ca compound and led to alginate-Ca binding. Taking advantage of the pH sensitivity, we prepared hydrogel microspheres with uniform size to entrap Lactobacillus rhamnosus ATCC 53103 through emulsification. In an acidic environment, the hydrogel structure remained compact with negligible pores to protect L. rhamnosus ATCC 53103. However, in a neutral intestinal environment, the hydrogel structure gradually disassembled because of the Ca2+release from the hydrogel, which caused cell release. Therefore, a pH-responsive carrier was developed for the protection and the controlled release of cells in gastrointestinal tract, thus providing potential for oral delivery of probiotics.
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China; University of the Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China; University of the Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Meng
authors.initials: M
authors.lastname: Gao
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China; University of the Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China; University of the Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Ruyun
authors.initials: R
authors.lastname: Lou
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China.
authors.forename: Hongguo
authors.initials: H
authors.lastname: Xie
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China. Electronic address: yuwt@dicp.ac.cn.
authors.forename: Weiting
authors.initials: W
authors.lastname: Yu
authors.affiliation: College of Environment and Chemical Engineering, Dalian University, Dalian Economic Technological Development Zone, Dalian 116622, PR China. Electronic address: liuxd@dicp.ac.cn.
authors.forename: Xiudong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Laboratory of Biomedical Materials Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Ma
mesh_terms: D000464:Alginates / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D052201:Lacticaseibacillus rhamnosus; D019936:Probiotics / Q000008:administration & dosage*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020100:Hydrogels; D020723:Glucuronic Acid; D004492:Edetic Acid; D002118:Calcium
keywords: Controlled release; EDTA-Ca-Alg; Hydrogel; Lactobacillus rhamnosus ATCC 53103; pH-Responsive carrier