title: Evaluation of functional characteristics of preactivated thiolated chitosan as potential therapeutic agent for dry mouth syndrome.
abstract: OBJECTIVE
  The objective of this study was to investigate preactivated thiomers for their potential in the treatment of dry mouth syndrome.
  
  
  METHODS
  Chitosan-thioglycolic-mercaptonicotinamide conjugates (chitosan-TGA-MNA) were synthesized by the oxidative S-S coupling of chitosan-thioglycolic acid (chitosan-TGA) with 6-mercaptonicotinamide (MNA). Test disks were compressed out of unmodified chitosan, chitosan-TGA (thiomers) and chitosan-TGA-MNA conjugates to investigate cohesive properties, cytotoxicity assays and mucoadhesion studies.
  
  
  RESULTS
  Immobilizing the MNA achieved higher swelling and cohesive properties of chitosan-TGA-MNA conjugates compared to unmodified chitosan. Rotating cylinder studies displayed a 3.1-fold improvement of mucoadhesiveness of chitosan-TGA-MNA conjugates compared to thiolated polymers. Findings in tensile strength were in good agreement with rotating cylinder ones. Furthermore, preactivated thiomers exhibit higher stability. All conjugates were found non-toxic against Caco-2 cells.
  
  
  CONCLUSIONS
  Preactivated thiolated chitosan could be a promising system for the treatment of dry mouth syndrome where mucosa requires lubrication and mucoadhesiveness.
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria.
authors.forename: Flavia
authors.initials: F
authors.lastname: Laffleur
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Fischer
authors.affiliation: Institute of Analytical Chemistry & Radiochemistry, CCB - Center for Chemistry and Biomedicine, University of Innsbruck, Austria.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmutzler
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria.
authors.forename: Fabian
authors.initials: F
authors.lastname: Hintzen
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria. Electronic address: andreas.bernkop@uibk.ac.at.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bernkop-Schnürch
mesh_terms: D045744:Cell Line, Tumor; D048271:Chitosan / Q000737:chemistry / Q000627:therapeutic use*; D006801:Humans; D008422:Materials Testing; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D014987:Xerostomia / Q000188:drug therapy*
chemical_list: D013438:Sulfhydryl Compounds; D048271:Chitosan
keywords: Chitosan–thioglycolic acid; Dry mouth syndrome; Mercaptonicotinamide; Preactivated thiomers; Thiomers