Development and Evaluation of Nanoparticle-Loaded Hydrogel of Co-trimoxazole

In this study, development of nanoparticle loaded hydrogel of Cotrimoxazole that could simultaneously deliver trimethoprim and sulfamethoxazole at the site of wound to promote and accelerate wound healing is planned. Chitosan nanoparticles loaded with Co-trimoxazole were prepared by ionic gelation method. Chitosan nanoparticles were optimized and F5 formulation was selected 5:1 Chitosan TPP ratio for this Homogenization speed was kept at 5000 rpm and an average size of 209.8 ± 34.6 was obtained, PDI was found to be 0.26 ± 0.04, the zeta potential of the nanoparticles was found to be + 24.7 ± 3.12 and the entrapment efficiency of 89.7 ± 3.1 % was seen. Hydrogel was prepared and optimized on the basis of Conc. of Carbopol 940 1.2%, viscosity 14.953 ± 0.51, pH 5.9 ± 0.04, Swelling index 250 ± 4.71 and Spreadability 34 ± 3.5. Antimicrobial study and Minimum Inhibitory Concentration (MIC) were performed and it was observed that the MIC of Co-trimoxazole was 2 µg/mL and the hydrogel formulation showed maximum zone of inhibition 3.7 ± 0.3 after 72 hours against plain drug and marketed formulation. The rate of wound contraction was calculated in percentage and at 15th day the control group had 72% ± 3.9%, Marketed formulation group had 36% ± 5.2% and the hydrogel formulation had reduced the wound size to mere 4% ± 1.3% only. Hydrogel loaded with nanoparticles of Co-trimoxazole that possessed optimum rheology and provided sustained drug release was successfully prepared. The developed hydrogel formulation was found to heal the wound 1.5 times faster than the marketed formulation thus providing us with a better alternative to other conventional wound dressings.