title: Design and in vitro characterization of buccoadhesive tablets of timolol maleate.
abstract: OBJECTIVE
  The purpose of this work was to develop and evaluate buccoadhesive tablets of timolol maleate (TM) due to its potential to circumvent the first-pass metabolism and to improve its bioavailability.
  
  
  METHODS
  The tablets were prepared by direct compression using two release modifying polymers, Carbopol 974P (Cp-974p) and sodium alginate (SA). A 3(2) full factorial design was employed to study the effect of independent variables, Cp-974p and SA, in various proportions in percent w/w, which influences the in vitro drug release and bioadhesive strengths. Physicochemical properties of the drug were evaluated by ultraviolet, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and powder X-ray diffraction (P-XRD). Tablets were evaluated for hardness, thickness, weight variation, drug content, surface pH, swelling index, bioadhesive force and in vitro drug release.
  
  
  RESULTS
  The FTIR and DSC studies showed no evidence of interactions between drug, polymers and excipients. The P-XRD study revealed that crystallinity of TM remain unchanged in optimized formulation tablet. Formulation F9 achieves an in vitro drug release of 98.967% ± 0.28 at 8 h and a bioadhesive force of 0.088 N ± 0.01211.
  
  
  CONCLUSIONS
  We successfully developed buccal tablet formulations of TM and describe a non-Fickian-type anomalous transport as the release mechanism.
authors.affiliation: Department of Pharmaceutics, MGV's Pharmacy College , Panchavati, Dist-Nashik, Maharashtra , India .
authors.forename: Sachin S
authors.initials: SS
authors.lastname: Gaikwad
authors.forename: Shital K
authors.initials: SK
authors.lastname: Thombre
authors.forename: Yogesh K
authors.initials: YK
authors.lastname: Kale
authors.forename: Sheetal B
authors.initials: SB
authors.lastname: Gondkar
authors.forename: Avinash B
authors.initials: AB
authors.lastname: Darekar
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000268:Adhesiveness; D000278:Administration, Buccal; D000464:Alginates / Q000737:chemistry; D001682:Biological Availability; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D004355:Drug Stability; D005079:Excipients / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D033362:Powder Diffraction; D017550:Spectroscopy, Fourier Transform Infrared; D013607:Tablets; D013999:Timolol / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D000179:Acrylates; D000464:Alginates; D005079:Excipients; D006603:Hexuronic Acids; D013607:Tablets; C117167:carbopol 974P NF; D013999:Timolol; D020723:Glucuronic Acid