The present study was aimed to design an in-situ ophthalmic gel formulation of timolol maleate containing combination of pH induced gelling agent i.e. carbopol 934P and thermo-sensitive gelling agent i.e. methyl cellulose A4M and to evaluate the effect of methyl cellulose A4M upon addition to carbopol 934P with respect to rheological characteristic. Brookfield viscometer LV-I model is used to check the rheological behavior. Addition of methyl cellulose to carbopol 934P increases the viscosity of system that is why because methyl cellulose works as a viscolizer and thus the release of drug from gel is retarded. After evaluation it was found that the combination of both the polymer shows the thixotrophic behavior which is an acceptable criterion to perform better in the ocular system and also acceptable as these systems prove less irritation to the cornea. As a complementary to rheological evaluation, the in-situ gel is further evaluated for in-vitro release study and statistical data analysis. The best fit model with highest correlation coefficient was shown in Higuchi�s model. The regression value is closer to unity (R2 = 0.9949). The system also shows the sustained drug delivery system and follows the fickanian diffusion which shows that the drug release from the in-situ ocular drug delivery system is diffusion controlled; it has the advantages over the eye drop solution which are instilled in eyes or to apply gel or ointment formulation in to the eyes.
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