Formulation and Characterization of Bilayer Floating Tablets of Glipizide & Lisinopril

*Sheetal Buddhadev¹, Raval Kashyap², Dr. Sandip Buddhadev^3 
1Assistant Professor, Department of Pharmaceeutics, Noble Pharmacy College, Junagadh
²HOD, Department of QA, Noble Pharmacy College, Junagadh
³Associate Prof., Department of Dravyaguna, Government Ayurved College, Junagadh

A B S T R A C T
The purpose of the study is to prepare Bilayer floating tablets containing Glipizide as sustained release and Lisinopril as immediate release which can be used to treat both the diseases concomitantly. Sustained layer were prepared by direct compression method using the release retarding polymer HPMC K4M & HPMC K100M and gas generating agent sodium bicarbonate and citric acid. Immediate release layer were prepared by direct compression method using superdisintegrants such as sodium starch glycolate and pregelatinized starch. Bilayer tablets were prepared with different quantities of polymers like HPMC K4 M and HPMC K100M. A 3² Full factorial design was used for optimization of polymers. The quantity of HPMC K4M (X1) and HPMC K100M (X2) were selected as independent variables and Floating Duration, Percentage drug release at 8 h(Q₈)and Percentage drug release at 20 h(Q₂₀) were selected as dependent variables.  Tablets were evaluated. The formulations (FT4) showed release of Lisinopril within 30 min followed by sustained release of Glipizide (98.86%) at 20 h. The kinetics release of optimize batch FT4 was best explained by first order and Korsmeyer–Peppas. The IR spectrum revealed that there is no disturbance in the principal peaks of pure drugs Glipizide and Lisinopril. There is  no incompatibility of them with excipients.
Keywords: Glipizide, Lisinopril, Floating, Immediate release, Bilayer Tablets.