Laser-assisted triggered-drug release from silver nanoparticles-grafted dual-responsive polymer.

Laser assisted drug release from a synthesized plain polymer composed of poly (butyl methacrylate-co-acrylamide-co-methacrylic acid) [P(BMA-co-AAm-co-MAA)] and a metallo-polymer composed of silver nanoparticles (Ag NPs) grafted plain polymer (the nanocomposite) were studied to investigate their capability to serve as drug carriers. Positive temperature dependent swelling changes were observed for both carriers and their thermal sensitivity and thermal and optical switching properties were investigated in two buffered solutions. An acidic solution with pH=1.2 to simulate stomach body condition and a neutral solution with pH=7.4 to simulate intestine condition. Reversible phase transition (collapsing/swelling) with fast response time in the order of few seconds were observed by applying heat or by applying light radiation at the surface plasmon resonance wavelength of the attached NPs. Finally, cumulative release (%) of ofloxacin antibiotic as a model drug was investigated for both thermal and optical switching conditions. Based on these results, pulsatile release was observed which have the "on" and "off" states at higher and lower temperatures with respect to their volume-phase transition temperatures respectively.