Abstract

The aim of the present study was to formulate injectable in situ gel matrix containing metoprolol succinate by
cold method, using the thermosensitive polymer Pluronic F 127 (20%) together with carbopol 934P, HPMC and
SCMC. The drug polymer compatibility was studied by FTIR. The formulations were evaluated for clarity,
sterility, gelation temperature, gelation time, viscosity, drug content and drug release. Gelation temperature for
the formulations was found in between 34-41ºC with gelation time varying from 1-6 mins. The drug content for
the prepared formulations was found to be 97 to 100%. The non-irritant nature of the developed formulation
was confirmed by the HET-CAM test. In vivo appearance studies were conducted on dead calf ear. The
optimized formulation C12 had viscosity suitable for injecting, formulation C12 showed controlled drug release
and it was found to be 99.53% upto 12 h. The stability studies performed on C12 showed no single change in
physical appearance and drug release. It was concluded that the drug release performance was greatly affected
by the polymer used in the preparation of injectable in situ gel.