The primary motive is to develop the solid lipid nanoparticles formulation of atazanavir with enhanced dissolution rate. The prepared Atazanavir SLNs formulation batches (i.e.,18 formulations), composed of solid-lipid (Tri-stearin/ Witepsol E85), surfactants and stabilizer (Cremophor RH40, Pluronic F68, Tego care 450 and Tween 80) were fabricated employing hot homogenization followed by the ultrasonication. All the formulations were evaluated for particle Size, zeta potential, drug content, Entrapment Efficiency and in-vitro drug release. Optimised formulation was subjected for particle Size, zeta potential, FTIR, SEM and stability studies. The mean particle size, zeta potential, drug content, entrapment efficiency (EE), and in-vitro drug release profile of atazanavir loaded SLNs were found to be ranged from 59.42 nm – 146.29 nm., -15.1mV to -23.57mV, 94.61 to 99.72%, 94.83 to 99.52%, .and 54.90 to 81.40% at the end of 12 hours respectively. The amount of drug released from the SLN dispersions generated using Witepsol E85 as the lipid matrix, with tego care 450 as the surfactant (as shown highest for F18= 99.72±0.46%), was significantly controlled and regulated than that from the atazanavir-pure drug solution (31.09±1.16%). The optimized formulation (F18) exhibited particle size of 79.21 nm, zeta potential -16.1mV and FTIR studies revealed that there is no incompatibility between drug and excipients, SEM images exhibited nanoparticles to be more porous and in spherical shape. Stability studies indicated F18 formulation was stable for 3months.The results implied that the proposed way of SLN preparation could be considered as a proper method for production of atazanavir loaded colloidal carrier system

Atazanavir, solid-lipid nanoparticle, Particle size, In-vitro drug release, FTIR studies