Enhanced L-Asparaginase Stability Through Immobilization in Supramolecular Nanogels of Peg-Grafted Poly Hpma With Bis(Α-Cyclodextrin) Publisher



Monajati M^{1, 2} ; Tamaddon AM^{1, 2, 3} ; Abolmaali SS^{1, 2} ; Yousefi G^{2, 3} ; Borandeh S² ; Dinarvand R^{4, 5}
Source: Biochemical Engineering Journal Published:2023

Abstract

This paper presents the fabrication of a biocompatible supramolecular nanogel containing immobilized L-asparaginase (ASNase), an anti-leukemic therapeutic agent, to improve the enzyme's physicochemical stability. The ASNase-conjugated random copolymer of N-(2-Hydroxypropyl)methacrylamide (HPMA) and polyethylene glycol (PEG) acrylate was simply combined with inter-molecularly crosslinked α-cyclodextrin (bisCD) in physiologic condition to prepare inclusion complex nanogels. The introduction of bisCD led to the formation of discrete, homogenous, and spherical nanogels with a mean projected diameter of 148 nm for the best formulation of ASNase bioconjugate in terms of polymer succination ratio and polymer:protein ratio. The Michaelis-Menten constant (Km) for immobilized ASNase was 1.6-fold lower than the free form, indicating a higher affinity for the asparagine substrate. The ASNase immobilization significantly extended the pH stability range. In addition, when compared to the free enzyme, ASNase-bisCD nanogel exhibited superior stability against elevated temperature, freeze-thaw cycles, and proteolysis. Overall, the immobilization of ASNase in bisCD nanogels yields a novel stabilized preparation with promising biomedical applications. © 2023 Elsevier B.V.