When low ocular bioavailability of conventional eye drops is taken into account for ocular bacterial conjunctivitis, there is a need for developing efficient modern drug delivery systems. In this study, PLGA based nanoparticles (NPs) were designed for levofloxacin hemihydrate (LVF) ophthalmic delivery to improve precorneal residence time and ocular penetration. This study investigates formulation and process modification to improve the versatility of the nanoprecipitation technique. The principal objective of this work was to explore the influence of modifications on particle size (PS), size distribution, zeta potential (ZP), thermal, solid-state characteristics and entrapment efficiency (EE)% values of the NPs. Modification of formulation parameters show significant improvement of physicochemical properties of NPs. Selection of NP2 and NP3 as optimum formulations for better characteristics (considerable high EE%, homogenous amorphous matrix formation, smaller PS, narrower size distribution and promising high ZP) would increase stability and enhance ocular bioavailability with prolonged release pattern.