PEG modification enhances the in vivo stability of bioactive proteins immobilized on magnetic nanoparticles

• Published in: Biotechnology letters Vol. 42; no. 8; pp. 1407 - 1418
• Main Authors: Xu, Qing, Hou, Jing, Rao, Jun, Li, Guo-Hao, Liu, Yun-Long, Zhou, Jie
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2020; Springer Nature B.V
• Subjects: Animals; Applied Microbiology; beta-Glucosidase - chemistry; beta-Glucosidase - metabolism; beta-Glucosidase - pharmacokinetics; Biochemistry; Biological activity; Biomedical and Life Sciences; Biotechnology; Cellobiase; Coupling (molecular); Coupling methods; Deionization; Enzymatic activity; Enzyme activity; Enzyme Stability; Enzymes; Enzymes, Immobilized - chemistry; Enzymes, Immobilized - metabolism; Enzymes, Immobilized - pharmacokinetics; Glucosidase; Immobilization; In vivo methods and tests; Life Sciences; Magnetite Nanoparticles - chemistry; Microbiology; Nanoparticles; Original Research Paper; Particle Size; Pharmacokinetics; Physicochemical properties; Polyethylene glycol; Polyethylene Glycols - chemistry; Proteins; Rats; Rats, Sprague-Dawley; Stability analysis; Zeta potential; β-Glucosidase; Immobilization; β-Glucosidase; PEG modification; Magnetic nanoparticles
• DOI: 10.1007/s10529-020-02867-4
• ISSN: 0141-5492

Objective To increase the in vivo stability of bioactive proteins via optimized loading methods. Results β-Glucosidase (β-Glu), as a model protein, was immobilized on magnetic nanoparticles(denoted as MNP-β-Glu) by chemical coupling methods and was further modified by poly(ethylene glycol) (PEG) molecules (denoted as MNP-β-Glu-PEG) to increase its stability. The physicochemical properties of the as-prepared nanohybrids, including the particle size, zeta potential, and enzyme activity, were well characterized. The proper MNP/β-Glu feed ratio was important for optimizing the particle size. Analysis of enzyme activity showed that the stability of immobilized β-Glu compared with free β-Glu was lower in deionized water and higher in blood serum at 37 °C. MNP-β-Glu-PEG retained 77.9% of the initial activity within 30 days at 4 °C, whereas the free enzyme retained only 58.2%. Pharmacokinetic studies of Sprague–Dawley (SD) rats showed that the MNP-β-Glu-PEG group retained a higher enzyme activity in vivo (41.46% after 50 min) than the MNP-β-Glu group (0.03% after 50 min) and the β-Glu group (0.37% after 50 min). Moreover, in contrast to the MNP-β-Glu group, the enzyme activity was not fully synchronous with the decrease in the Fe concentration in the MNP-β-Glu-PEG group. Conclusions All findings indicated that the method of immobilization on magnetic nanoparticles and PEG modification is promising for the application of bioactive proteins in vivo.