Enzyme Release from Polyion Complex by Extremely Low Frequency Magnetic Field

Kseniya Yu Vlasova,Alexander G Majouga,Alexander V Kabanov,Alexander O Zhigachev,Maxim A Abakumov,Natalia L Klyachko,Dmitry Yu Golovin,Sergey L Gribanovsky,Andrey А Poloznikov,Marina Sokolsky-Papkov,Yuri I Golovin,Hemant Vishwasrao

doi:10.1038/s41598-020-61364-w

Abstract

Remote nano-magneto-mechanical actuation of magnetic nanoparticles (MNPs) by non-heating extremely low frequency magnetic field (ELF MF) is explored as a tool for non-invasive modification of bionanomaterials in pharmaceutical and medical applications. Here we study the effects of ELF MF (30–160 Hz, 8–120 kA/m) on the activity and release of a model enzyme, superoxide dismutase 1 (SOD1) immobilized by polyion coupling on dispersed MNPs aggregates coated with poly(L-lysine)-block-poly(ethylene glycol) block copolymer (s-MNPs). Such fields do not cause any considerable heating of MNPs but promote their rotating-oscillating mechanical motion that produces mechanical forces and deformations in adjacent materials. We observed the changes in the catalytic activity of immobilized SOD1 as well as its release from the s-MNPs/SOD1 polyion complex upon application of the ELF MF for 5 to 15 min. At longer exposures (25 min) the s-MNPs/SOD1 dispersion destabilizes. The bell-shaped effect of the field frequency with maximum at f = 50 Hz and saturation effect of field strength (between 30 kA/m and 120 kA/m at f = 50 Hz) are reported and explained. The findings are significant as one early indication of the nano-magneto-mechanical disruption by ELF MF of cooperative polyion complexes that are widely used for design of current functional healthcare bionanomaterials.

Highlights

Non-invasive functional control of bionanomaterials in inaccessible areas of a human body could greatly advance development of diagnostics and therapeutic modalities[1]
This paper for the first time describes the release of the enzyme, superoxide dismutase 1 (SOD1), from the polyion complex formed by electrostatic complexation of this enzyme with a cationic polymer coated magnetic nanoparticles (MNPs) via activation by non-heating extremely low frequency magnetic field (ELF MF)
The saturation magnetization normalized for the magnetite mass was 58 emu/g and 57 emu/g for bare MNPs and stabilized MNPs (s-MNPs) respectively (Supporting information, Figure S1), which is consistent with the literature data for spherical magnetite MNPs with Dm = 10 nm[27]

Summary

Introduction

Non-invasive functional control of bionanomaterials in inaccessible areas of a human body (e.g., biochemical reactions, drug release, gene expression, etc.) could greatly advance development of diagnostics and therapeutic modalities[1] This control can be accomplished by remote actuation of nanoparticles by external fields[2,3,4,5,6]. An alternative nano-magneto-mechanical actuation of MNPs by non-heating extremely low frequency magnetic field (ELF MF) has attracted increasing attention in drug delivery and nanomedicine[13,14,15,16,17]. The phenomenon of nano-magneto-mechanical actuation is linked to the ability of MNPs to undergo mechanical motion in ELF MF and as a consequence produce mechanical forces and deformations in adjacent materials It is well known, that a single-domain MNPs can relax in an external magnetic field, reducing an angle between the MNPs magnetic moment μ and the field vector H18–20. This paper for the first time describes the release of the enzyme, superoxide dismutase 1 (SOD1), from the polyion complex formed by electrostatic complexation of this enzyme with a cationic polymer coated MNPs via activation by non-heating ELF MF

Methods

Results

Conclusion