title: Useful Extend-release Chitosan Tablets with High Antioxidant Activity.
abstract: The antioxidant properties of different low molecular weight (LMW) chitosans (CS1; 22 kDa, CS2; 38 kDa, CS3; 52 kDa, CS4; 81 kDa) were examined for possible use in extended-release tablets. The criteria used were the ability of the chitosans to reduce Cu2+, and hydroxyl and superoxide radicals and N-centered radicals derived from 1,1'-diphenyl-2-picrylhydrazyl, via the use of ESR spectrometry. CS2 showed the highest scavenging activity. CS1 and CS3, however, were much less effective and CS4 was not a viable antioxidant. The results suggest that CS2 could be useful in combating the development of oxidative stress. A series of chitosan tablets were prepared using a spray drying method and evaluated as an extended-release matrix tablet using theophylline (TPH) as a model drug. The release of TPH from the different MW chitosan tablets increased with increasing MW of the chitosan used. CS2, CS3 and CS4 showed a reasonable release activity, but CS1 showed the shortest release activity. Moreover, the CS2-TPH tablet showed the highest scavenging activity of the three chitosan tablets (CS2-CS4) using 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radicals. These results suggest that a CS2-TPH tablet could be potentially useful in an extended-release matrix tablet with a high antioxidant activity.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.
authors.forename: Taira
authors.initials: T
authors.lastname: Yasufuku
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Anraku
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kondo
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Hata
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.
authors.forename: Junzo
authors.initials: J
authors.lastname: Hirose
authors.affiliation: Dainichiseika Color & Chemicals Mfg. Co., Ltd., 7-6, Nihonbashi Bakuro-cho 1-chome, Chuo-ku, Tokyo, 103-8383, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kobayashi
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan. tomida@fupharm.fukuyama-u.ac.jp.
authors.forename: Hisao
authors.initials: H
authors.lastname: Tomida
keywords: antioxidant; chitosan; extend-release; matrix tablet; molecular weight; radicals