title: Resistant starch film-coated microparticles for an oral colon-specific polypeptide delivery system and its release behaviors.
abstract: For the delivery of bioactive components to the colon, an oral colon-specific controlled release system coated with a resistant starch-based film through aqueous dispersion coating process was developed. Starch was modified by a high-temperature-pressure reaction, enzymatic debranching, and retrogradation, resulting in a dramatic increase in the resistibility against enzymatic digestion (meaning the formation of resistant starch, specifically RS3). This increase could be associated with an increase in the relative crystallinity, a greater amount of starch molecular aggregation structure, and the formation of a compact mass fractal structure, resulting from the treatment. The microparticles coated with this RS3 film showed an excellent controlled release property. In streptozotocin (STZ)-induced type II diabetic rats, the RS3 film-coated insulin-loaded microparticles exhibited the ability to steadily decrease the plasma glucose level initially and then maintain the plasma glucose level within the normal range for total 14-22 h with different insulin dosages after oral administration; no glycopenia or glycemic fluctuation was observed. Therefore, the potential of this new RS3 film-coated microparticle system has been demonstrated for the accurate delivery of bioactive polypeptides or protein to the colon.
authors.affiliation: Ministry of Education Engineering Research Centre of Starch and Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology , Guangzhou 510640, China.
authors.forename: Wenbei
authors.initials: W
authors.lastname: Situ
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Xueyu
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaoxi
authors.initials: X
authors.lastname: Li
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003106:Colon / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004063:Digestion; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods*; D007328:Insulin / Q000008:administration & dosage* / Q000737:chemistry; D008297:Male; D053758:Nanoparticles / Q000737:chemistry; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013213:Starch / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D004337:Drug Carriers; D007328:Insulin; D010455:Peptides; D013213:Starch