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Updated: Apr 4, 2026

Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
β-Lactoglobulin (BLG) binding to highly charged cationic polymer-grafted magnetic nanoparticles: effect of ionic
Li Qin1, Yisheng Xu2, Haoya Han1
1State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
Abstract:
Poly(2-(methacryloyloxy)ethyltrimethyl ammonium chloride) (PMATAC) modified magnetic nanoparticles (NPs) with a high zeta potential of ca. 50mV were synthesized by atom transfer radical polymerization (ATRP). The prepared NPs consist of a magnetic core around 13nm and a PMATAC shell around 20nm attached on the surface of magnetic nanoparticles. Thermodynamic binding parameters between β-lactoglobulin and these polycationic NPs were investigated at different ionic strengths by high-resolution turbidimetry, dynamic light scattering (DLS), and isothermal titration calorimetry (ITC). Both turbidity and ITC show that binding affinities for BLG display a non-monotonic ionic strength dependence trend and a maximum appears at ionic strength of 50mM. Such observation should arise from the coeffects of protein charge anisotropy visualized by DelPhi electrostatic modeling and the strong electrostatic repulsion among highly charged NPs at a variety of ionic strengths.

