title: Formulation and optimization of mucoadhesive buccal patches of losartan potassium by using response surface methodology.
abstract: BACKGROUND
  This study was undertaken with an aim to systematically design a model of factors that would yield an optimized sustained release dosage form of an anti-hypertensive agent, losartan potassium, using response surface methodology (RSM) by employing 3(2) full factorial design.
  
  
  METHODS
  Mucoadhesive buccal patches were prepared using different grades of hydroxypropyl methylcellulose (HPMC) (K4M and K100M) and polyvinylpyrrolidone-K30 by solvent casting method. The amount of the release retardant polymers - HPMC K4M (X1) and HPMC K100M (X2) was taken as an independent variable. The dependent variables were the burst release in 30 min (Y1), cumulative percentage release of drug after 8 h (Y2) and swelling index (Y3) of the patches. In vitro release and swelling studies were carried out and the data were fitted to kinetic equations.
  
  
  RESULTS
  The physicochemical, bioadhesive, and swelling properties of patches were found to vary significantly depending on the viscosity of the polymers and their combination. Patches showed an initial burst release preceding a more gradual sustained release phase following a nonfickian diffusion process.
  
  
  CONCLUSIONS
  The results indicate that suitable bioadhesive buccal patches with desired permeability could be prepared, facilitated with the RSM.
authors.affiliation: School of Pharmacy, Suresh Gyan Vihar University, Jaipur, Rajasthan, India.
authors.forename: Md
authors.initials: M
authors.lastname: Ikram
authors.affiliation: Department of Pharmacy, Maharshi Dayanand University, Rohtak, Haryana, India.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Gilhotra
authors.affiliation: School of Pharmacy, Suresh Gyan Vihar University, Jaipur, Rajasthan, India.
authors.forename: Ritu Mehra
authors.initials: RM
authors.lastname: Gilhotra
keywords: 32 factorial design; losartan potassium; mucoadhesive; response surface methodology; sustained release