Chitosan coated alginate beads containing poly(N-isopropylacrylamide) for dual-stimuli-responsive drug release

摘要

Chitosan coated alginate beads containing poly(N-isopropylacrylamide) (PNIPAAM),were prepared to be used as a controlled pH/temperature sensitive drug deliverysystem with improved encapsulation efficiency and delayed release rate. The studied beadswere characterized by differential scanning calorimetry, scanning electron microscopy, andFourier transform infrared spectroscopy. Water uptake and release studies using indomethacinas a model drug were also performed. The drug loading efficiency of the beads with thepolyelectrolyte complex coating is significantly higher (84%) than that of the uncoated ones(74%). The equilibrium swelling of the developed materials was found to be pH- and thermoresponsive.For all the conditions it was found that the release profile was slower for the coatedbeads, indicating that the polyelectrolyte complex coating could slow down the release rateeffectively. These results suggest that the studied smart system has potential to be used as an effective pH/temperature sustainable delivery system for biomedical applications.