NIR-triggered drug delivery system based on tungsten disulfide nanosheets coated pH/temperature responsive polymer for controlled delivery of palbociclib: Release kinetics models

Background: Polymers that respond to changes in ambient conditions, such as physiological pH and temperature, have garnered increasing interest in the realm of drug delivery systems. In this study, a novel pH and temperature dual-responsive carrier was prepared for palbociclib delivery. Methods: The tungsten disulfide nanosheets were functionalized with allyl glycidyl ether, allyl alcohol, and Nvinylcaprolactam, and then grafted with 2, 3-diaminopyridine. The in-vitro drug release was studied in simulated cancer (pH=5.6) and blood (pH=7.4) fluids at different temperatures. Significant Findings: The in-vitro drug release test showed better release behavior at high temperatures in simulated cancer fluid compared to lower temperatures in simulated blood fluid, releasing about 87.53% of the entrapped drug within 6 h at 45 degrees C in simulated cancer fluid. The drug release shown the best fitting with the Korsmeyer-Peppas kinetic model. When the near-infrared laser irradiation was applied for 15 min, the drug release from the nanocarrier was three times higher than that without the laser irradiation. The maximum sorption capacity of the drug was achieved at approximately 79.04 mg g-1 at pH=8 for 45 min at 25 degrees C. The sorption procedure was found to follow the Langmuir isotherm and a pseudo-2nd-order kinetic model quite well.