title: Calcium alginate beads as core carriers of 5-aminosalicylic acid.
abstract: The utilization of calcium alginate beads as core carriers for delayed dissolution followed by burst release as a potential method of intestinal site specific drug delivery was investigated. 5-Aminosalicylic acid was spray-coated on dried calcium alginate beads and then coated with different percentages of enteric coating polymer and/or sustained-release polymer. Beads coated with more than 6% (w/w) methacrylic copolymer plastisized with dibutyl sebacate and triethyl citrate resisted release in 2-hr acid fluid challenge and allowed immediate dissolution upon transfer to simulated intestinal fluid. With 6% (w/w) methacrylic copolymer on top of 4% (w/w) ethylcellulose polymer, the major portion of drug did not release in 2 hr of acid treatment or the next 3 hr of simulated intestinal fluid treatment. This dosage form provides the possibility to deliver drug to the lower intestinal tract with minimal early release, followed by sustained release in the colon.
authors.affiliation: College of Pharmacy, Oregon State University, Corvallis 97331.
authors.forename: S Y
authors.initials: SY
authors.lastname: Lin
authors.forename: J W
authors.initials: JW
authors.lastname: Ayres
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000636:Aminosalicylic Acids / Q000008:administration & dosage* / Q000737:chemistry; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D016503:Drug Delivery Systems; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D007413:Intestinal Mucosa / Q000378:metabolism; D019804:Mesalamine; D008863:Microspheres; D011108:Polymers; D012995:Solubility
chemical_list: D000464:Alginates; D000636:Aminosalicylic Acids; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D006603:Hexuronic Acids; D011108:Polymers; D019804:Mesalamine; D020723:Glucuronic Acid