A Y-shaped miktoarm amphiphilic block copolymer composed of poly(ε-caprolactone) and poly(N-isopropylacrylamide) as a thermal-responsive nano-micellar carrier for anticancerdrugs

A thermal-responsive Y-shaped amphiphilic block copolymer, namely poly(Nisopropylacrylamide- block-[poly(ε-caprolactone)]2 (PNIPAAm-b-PCL2), was synthesized through thecombination of atom transfer radical polymerization (ATRP) and ring-opening polymerization (ROP) techniques, and its potential as smart anti-cancer drug delivery system (DDS) was investigated preliminary. The fabricated polymers were characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies, as well as gel permeation chromatography (GPC) analysis. The self-assembly behavior of the fabricated PNIPAAm-b-PCL2 copolymer under thermal stimuli was investigated using dynamic light scattering (DLS) equipment, as well as ultraviolet–visible (UV–vis) spectroscopy. The lower critical solution temperature (LCST) of the synthesized PNIPAAm-b-PCL2 was calculated to be 39-41 °C using UV–vis spectroscopy. The doxorubicin hydrochloride (Dox), as a universal anti-cancer drug, loading and encapsulation capacitiesof the fabricated PNIPAAm-b-PCL2 were calculated to be 62 ± 3%, and 75 ± 4%, respectively. The formulated PNIPAAm-b-PCL2-Dox at 37 °C showed low drug release value (up to 46.5% during 40 hours). In contrast, at 40 °C the drug release value was increased significantly (up to 88% during 40 hours) due the collapse of PNIPAAm segment that lead to release of encapsulated cargo. According to this result as well as the higher temperature value of cancerous cells than those of the normal cells, the formulated PNIPAAm-b-PCL2-Dox has potential for chemotherapy of various cancers. )

کلیدواژه ها:

Cancer chemotherapy ، Stimuli responsive ، Nano-micellar carrier