Comparative studies of lamivudine-zidovudine nanoparticles for the selective uptake by macrophages.

The present study investigates the specific drug targeting of anti retroviral drugs, such as lamivudine and zidovudine, after intraperitoneal (i.p) injection by incorporation into polymeric nanoparticles (PNs) and solid lipid nanoparticles (SLNs). Our results showed that Glyceryl Monosterate-Poloxamer 188 SLNs (average diameter of 522.466 nm) showed slow drug release rates (63.18% of lamivudine and 62.37% of zidovudine were released in 12 hrs) among all the SLN formulations. For Poly lactic-co-glycolic acid (PLGA)-Poloxamer 188 PNs (average diameter of 70.348 nm), there were faster release rates of both lamivudine and zidovudine (97% and 94.06%, respectively, in 12 hrs). Tissue distribution studies were carried out in mice and concentrations of drugs in different organs were determined using high performance liquid chromatography (HPLC) after i.p. administration. Glyceryl Monosterate-Poloxamer 188 SLNs and PLGA-Poloxamer 188 PNs showed increase in the distribution of lamivudine and zidovudine to liver and spleen when compared to the drugs in solution. Also, Glyceryl Monosterate-P 188 SLNs showed higher concentration of drugs in RES organs than PLGA-P 188 PNs.