High glycolic poly (DL lactic co glycolic acid) nanoparticles for controlled release of meropenem

Nanospheres of low molecular weight poly lactic co glycolic acid (PLGA) with high glycolic acid content (10:90) and polylactic acid (PLA) are synthesized and loaded with meropenem, a broad spectrum antibiotic. The loading efficiency of the drug is 82 and 70% in PLGA 10:90 and PLA respectively. The rate of drug release is higher with PLGA 10:90 (3.2 μg/s) than with PLA (2.4 μg/s). Eighty and 60% of the encapsulated drug is released from the two polymers in 30 days respectively. Initial burst followed by sustained drug release is observed which is mathematically explained using a biphasic model. The drug release from the former polymer leads to two times lower E. coli growth than the release from the latter. The nanoparticles are biocompatible with no significant effect on the viability of 3T3 cells. This study indicates that PLGA 10:90 can be used for the delivery of antibiotics for interim period, especially for post orthopaedic surgeries.