Synthesis and characterization of non-toxic and thermo-sensitive poly(N-isopropylacrylamide)-grafted cashew gum nanoparticles as a potential epirubicin delivery matrix

摘要

Cashew gum (CG) was grafted with N-isopropylacrylamide (NIPA) by radical polymerization to originate a stimuli-sensitive copolymer for drug delivery purposes. NMR and IR spectroscopy confirmed the insertion of NIPA onto the cashew gum chains. The graft copolymer (CG:NIPA) demonstrated thermal responsiveness. The critical aggregation concentration of the copolymers at 25 degrees C was higher than at 50 degrees C. At temperatures lower than the LCST, the nanoparticle size ranged from 12 to 21 nm, depending on the CG:NIPA ratio, but above the LCST the particles aggregated, increasing the particle size. Regarding the potential for future oral application, the nanoparticles showed no cytotoxic activity against the Caco(2) and HT29-MTX intestine cell lines. Epirubicin was encapsulated into nanoparticles of CG-NIPA (1:1), resulting in a 64% association efficiency and 22% loading capacity. Thus, the CG:NIPA graft copolymer demonstrates good potential for used in controlled drug delivery systems. (C) 2016 Elsevier Ltd. All rights reserved.