FORMULATION DEVELOPMENT AND IN-VITRO EVALUATION OF DOUBLE LAYER TABLET OF SUSTAINED RELEASE (S.R.) FLURBIPROFEN AND IMMEDIATE RELEASE DOXYCYCLINE

Purpose: To formulate and characterize the bi-layer tablet of doxycycline immediate release and flurbiprofen sustained release. Method: Bi-layer tablets were formulated by wet granulation method. Ethyl cellulose and HPMC K 100 were used as polymer for sustained release layer. Five immediate release formulations were developed with varying excipients. Bi-layer tablets were evaluated by pre formulation and post formulation parameters as stated by USP. Dissolution was conducted in 0.1 N HCl and 6.8 phosphate buffer and resulting data were analyzed statistically by one way ANOVA and drug release kinetics was studied using various pharmacokinetic models. Results: Data from pre formulation confirmed the purity of doxycycline hyclate and flurbiprofen. FTIR confirmed the absence of incompatibility between drugs and excipients. Dissolution profile in 0.1 N HCl and 6.8 phosphate buffer was according to USP guidelines. Regression coefficient (R2) values from kinetic analysis showed that release followed Higuchi model indicating release mechanism followed diffusion transport. Results of one way ANOVA confirmed that there is no statistically significant difference (p > 0.05) between drug dissolution of all formulations.  Conclusion: Bi-layer tablet was successfully formulated and it is a suitable approach to increase patient compliance and decrease cost of therapy.