Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Formulation of Chloramphenicol In situ Ophthalmic Gels Using Different Matrix Combinations

In situ ophthalmic gel is solution which form a gel when it is placed onto the eyes. It is intended to have a longer contact time in order to improve the response of therapy. In this experiment, In situ ophthalmic gels were formulated by using Chloramphenicol 0.5% and matrix combination of either 0.4% Hydroxy Propyl Cellulose (HPC) or 0.2% Hydroxy Propyl Methyl Cellulose (HPMC) with Sodium Alginate 0.4, 0.5 and 0.6%. All formulas were sterilized by autoclave at 115 oC for 30 minutes. Physical evaluation including organoleptic, pH, viscosity, and drug content showed that all formulas fulfilled the ophthalmic gel requirements according to USP and Indonesian Pharmacopoiea. From rheological study, it can be concluded that the gels had pseudoplastic flow. Either matrix combination of HPC or HPMC with sodium alginate were in solution form during storage and formed a gel once contacted with Simulated Tear Fluids (STF) at 37 oC, which reflected eyes condition. Chloramphenicol release from all in situ gels formulations showed sustained release profiles, and 80% release of drugs were retarded to four hours. Antibiotic potency tests of ophthalmic in situ gels showed that formulation with HPC and sodium alginate matrix (F1, F2 and F3) had potency of 99.22, 98.45, and 96.97% against Staphylococcus aureus as well as 96.46, 96.68, and 96.49% against Pseudomonas aeruginosa, while that with HPMC and sodium alginate matrix (F4, F5 and F6) had potency of 99.87, 98.45 and 95.58 against Staphylococcus aureus as well as 97.66, 95.05 and 94.42% against Pseudomonas aeruginosa. It can be concluded that in situ gel system with either HPC or HPMC in combination with sodium alginate provide sustained release of chloramphenicol. Formulation process, including sterilization did not affect antibiotic potency since it remained in the range of potency value requirements.