title: Thiol derivatization of Xanthan gum and its evaluation as a mucoadhesive polymer.
abstract: Thiol-derivatization of xanthan gum polysaccharide was carried out by esterification with mercaptopropionic acid and thioglycolic acid. Thiol-derivatization was confirmed by Fourier-transformed infra-red spectroscopy. Xanthan-mercaptopropionic acid conjugate and xanthan-thioglycolic acid conjugate were found to possess 432.68mM and 465.02mM of thiol groups as determined by Ellman's method respectively. Comparative evaluation of mucoadhesive property of metronidazole loaded buccal pellets of xanthan and thiolated xanthan gum using chicken buccal pouch membrane revealed higher ex vivo bioadhesion time of thiolated xanthan gum as compared to xanthan gum. Improved mucoadhesive property of thiolated xanthan gum over the xanthan gum can be attributed to the formation of disulfide bond between mucus and thiolated xanthan gum. In vitro release study conducted using phosphate buffer (pH 6.8) revealed a sustained release profile of metronidazole from thiolated xanthan pellets as compared to xanthan pellets. In conclusion, thiolation of xanthan improves its mucoadhesive property and sustained the release of metronidazole over a prolonged period.
authors.affiliation: Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science and Technology, Hisar 125001, Haryana, India. Electronic address: meenaxibhatia@gmail.com.
authors.forename: Meenakshi
authors.initials: M
authors.lastname: Bhatia
authors.affiliation: Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science and Technology, Hisar 125001, Haryana, India.
authors.forename: Munish
authors.initials: M
authors.lastname: Ahuja
authors.affiliation: Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science and Technology, Hisar 125001, Haryana, India.
authors.forename: Heena
authors.initials: H
authors.lastname: Mehta
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D000818:Animals; D002152:Calorimetry, Differential Scanning; D002645:Chickens; D065546:Drug Liberation; D007700:Kinetics; D008795:Metronidazole / Q000494:pharmacology; D008962:Models, Theoretical; D009061:Mouth Mucosa / Q000378:metabolism; D009077:Mucins / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013997:Time Factors
chemical_list: D000269:Adhesives; D009077:Mucins; D011108:Polymers; D011135:Polysaccharides, Bacterial; D013438:Sulfhydryl Compounds; D008795:Metronidazole; C002563:xanthan gum
keywords: Buccal pellets; Mucoadhesion; Thiolation; Xanthan gum