Formulation Design and Optimization of Novel Sustained Release GastroRetentive Floating Matrix Tablets of Ciprofloxacin HCl By Experimental Design

Abstract

The main objective of this study was to formulate and optimize a novel gastro-retentive 
floating matrix tablet of Ciprofloxacin hydrochloride with the help of Design of Experiment 
by using HPMC K100M and Sodium Alginate each with three different levels with an 
approach to increase gastric residence and thereby improve drug bioavailability. 
Ciprofloxacin hydrochloride is a fluoroquinolone antibiotic drug which is used for the 
effective treatment of infections caused by susceptible organism. It is stable at the gastric pH 
(acidic 1.2) and possesses elimination half – life of 4 hours. It is soluble in acidic medium 
and thus a gastroretentive floating tablet of the drug would enhance the extent of absorption. 
Ciprofloxacin hydrochloride gastro-retentive tablets were formulated by direct compression

method using variable concentration of HPMC K100M and Sodium Alginate as as the 
retardant polymers and sodium bicarbonate as a gas generating agent. From FTIR results 
confirm the absence of chemical interaction between the drug with the excipients used in 
tablet formulations. Also, there was no shift in the endotherm of in the drug- excipients 
mixtures indicating compatibility of drug with all the excipients. The resulting formulation 
has been evaluated for weight variation, thickness, hardness, friability, drug content, floating 
lag time, floating duration time and in-vitro drug release for 12 hours. In this study it was 
found that all the formulations showed compliance with pharmacopeial standards. Floating 
lag times of all the formulations were within 1 minute and Total floating time of all the 
formulations were more than 12 hours. In vitro release studies revealed that the release rate 
decreased with increase polymer proportion of retarding polymers. Formulation CHA7 (12% 
HPMC K100M and 6% SA) released 21 % in 1 h, 56 % in 6 h, 96 % in 12 h, with a FLT of 
1min, TFT up to 12 h. Hence, formulation CHA7 was considered the best formulation with 
desirable floating parameters and In vitro drug release profile. From the Kinetic model it was 
found that the optimized formulation CHA7 showed linearity in case of Zero order (R2
: 0.934) and Higuchi model (R2
: 0.959). By fitting data to Korsmeyer-Peppas model and ‘n’ 
value lying above 0.5 indicating non Fickian release.