RBx 11,760 is a bi-aryl oxazolidinone antibacterial agent active against Staphylococcus aureus but has poor solubility. Here we have encapsulated RBx 11,760 in PLA–PEG NPs with an aim to improve physicochemical, pharmacokinetics and in vivo efficacy. The average size and zeta potential of RBx 11,760 loaded NPs were found to be 106.4 nm and −22.2 mV, respectively. The absolute size of nanoparticles by HRTEM was found to be approximately 80 nm. In vitro antibacterial agar well diffusion assay showed clear zone of inhibition of bacterial growth.