PNVCL‐PEGMA nanohydrogels with tailored transition temperature for controlled delivery of 5‐fluorouracil

Abstract

ABSTRACT Sensitive nanohydrogels were prepared via surfactant free emulsion copolymerization of N ‐vinylcaprolactam and poly(ethylene glycol) methyl ether methacrylate, and either N ‐vinylpyrrolidone (VP) or 2‐methacryloyloxybenzoic acid (2MBA) to adjust the transition temperature ( T tr ). The crosslinker ethylene glycol dimethacrylate was used for the polymer network construction. The resulting nanohydrogel sizes are between 120 and 300 nm. ρ ‐Parameter, obtained from light scattering studies, suggests that core‐sell nanogels of flexible chains were obtained. T tr increases with increasing comonomer content (VP or 2MBA) and decreases with decreasing pH for 2MBA containing nanohydrogels. Nanohydrogels containing 15.5% of 2MBA exhibit T tr close to 38 °C. Nanogels are able to control the release of the loaded antineoplastic drug 5‐fluorouracil. For the prepared T/pH‐sensitive nanogels, the release is slower at pH 7.4 and 37 °C than at tumor conditions: pH 6 and 40 °C. Mathematical models were applied to evaluate the kinetics of drug release; Peppas model fitted best indicating a Fickian diffusion trough a sphere. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53 , 2662–2672