Preparation of Rilpivirine Nanosponges Using Different Methodologies

Rilpivirine is an analogue of a nucleoside that inhibits reverse transcriptase. Various polymers including ethyl cellulose (EC), -cyclodextrin (-CD), polyvinyl alcohol (PVA), polyvinyl pyrrolidone K-30 (PVP K-30), cross-linkers including dichloromethane (DCM), dimethyl carbonate (DMC), glutaraldehyde (GTLD), stabilisers including kondagogu gum (kgg), olibanum gum (OLG), and solvents like ethanol, methanol, dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), dist. water etc were used with different proportion with respective methods of preparation. Emulsion Ultrasonic-assisted synthesis, solvent synthesis, and the solvent diffusion method. It was decided that the solvent technique was the best option. FESEM imaging has been used to characterise nanosponges. The resultant batch (F8) made by the solvent approach was seen to have a nanoscale size distribution, a zeta potential of -12.2 mV, and a stable surface, as seen in a scanning electron microscope (SEM) image. Because of this promising outcome, the EC polymer, DMC cross-linker, and KGG stabiliser were selected for the next stage of scale-up. However, the surface roughness and form irregularity of other batches created using methods such as Emulsion Solvent Diffusion Method and Ultrasound Assisted Synthesis were shown by FESEM. The FESEM analysis proposed using the solvent approach to develop and scale up the batches further. Based on this finding, formulation development was continued, creating many batches using various ratios of polymer (EC): cross-linker (DMC), solvent (DMSO), and stabiliser (KGG).