Preparation And Drug Release Study Of Novel Nanopharmaceuticals With Polysorbate 80 Surface Adsorption

Most free drugs that cross the blood-brain barrier are characterized by high liposolubility, but they often have limited clinical applications because of poor dissolution and poor bioavailability. In this study, we prepared donepezil drug-loaded nanoparticles (DZP) with cholesterol-modified pullulan (CHP) as the nanocarrier (DZP-CHP) and surface modified the drug-loaded nanoparticles to improve the water solubility of donepezil while enhancing its targeting and sustained release. We determined the drug loading and encapsulation efficiency of DZP-CHP nanoparticles at different feed ratios. The mean +/- SD drug loading and entrapment efficiency were high: 13.52 +/- 2.03 and 86.54 +/- 1.31. On dynamic light-scattering measurement, mean +/- SD particle size was 260.7 +/- 1.76 nm, polydispersity index 0.123 +/- 0.004, and zeta potential -5.75 +/- 0.64 mV. DZP-CHP nanoparticles prepared with the optimal feed ratio (DZP : CHP = 1 :5) were coated with polysorbate 80, and the adsorption process was determined by isothermal titration calorimetry. We found good affinity between polysorbate 80 and DZP-CHP, with mean +/- SD coverage 2.7 +/- 0.372. The mean +/- SD drug loading and entrapment efficiency of polysorbate 80-emulsified DZP-CHP nanoparticles were 8.25 +/- 1.80 and 91.28 +/- 4.57, respectively, and the proportion of drug released by 72 h was 42.71%. Compared to DZP-CHP alone, PS-DZP-CHP can enhance the release of donepezil.