Enhanced and selective delivery of enzyme therapy to 9L-glioma tumor via magnetic targeting of PEG-modified, ß-glucosidase- conjugated iron oxide nanoparticles

Abstract

The stability of enzyme-conjugated magnetic iron oxide nanoparticles in plasma is of great importance for in vivo delivery of the conjugated enzyme. In this study, β-glucosidase was conjugated on aminated magnetic iron oxide nanoparticles using the glutaraldehyde method (β-Glu-MNP), and further PEGylated via N-hydroxysuccinimide chemistry. The PEG-modified, β-glucosidase-immobilized magnetic iron oxide nanoparticles (PEG-β-Glu-MNPs) were characterized by hydrodynamic diameter distribution, zeta potential, Fourier transform infrared spectroscopy, transmission electron microscopy, and a superconducting quantum interference device. The results showed that the multidomain structure and magnetization properties of these nanoparticles were conserved well throughout the synthesis steps, with an expected diameter increase and zeta potential shifts. The Michaelis constant was calculated to evaluate the activity of conjugated β-glucosidase on the magnetic iron oxide nanoparticles, indicating 73.0% and 65.4% of enzyme activity remaining for β-Glu-MNP and PEG-β-Glu-MNP, respectively. Both magnetophoretic mobility analysis and pharmacokinetics showed improved in vitro/in vivo stability of PEG-β-Glu-MNP compared with β-Glu-MNP. In vivo magnetic targeting of PEG-β-Glu-MNP was confirmed by magnetic resonance imaging and electron spin resonance analysis in a mouse model of subcutaneous 9L-glioma. Satisfactory accumulation of PEG-β-Glu-MNP in tumor tissue was successfully achieved, with an iron content of 627±45 nmol Fe/g tissue and β-glucosidase activity of 32.2±8.0 mU/g tissue.

Immobilization of β-Glucosidase from Thermatoga maritima on Chitin-functionalized Magnetic Nanoparticle via a Novel Thermostable Chitin-binding Domain

“…The characteristic peak at 1689.46 cm −1 revealed the presence of an amide-I region of Tm-β-Glu which confirmed the successful immobilization of Tm-β-Glu onto Ch-MNPs. The broadband at around 3320 cm −1 after immobilization of Tm-β-Glu-Tt-ChBD could be due to association intermolecular bonds from N-H stretching vibration with O-H stretching vibration in the β-Glu molecules 28 , which confirmed successful immobilization of Tm-β-Glu-Tt-ChBD on Ch-MNPs. www.nature.com/scientificreports www.nature.com/scientificreports/ Also, through the analysis of user access strategies in the correlation between Fe 3 O 4 MNPs synthesis with Tm-β-Glu-Tt-ChBD and specificity binding through target molecules using AutoDock software to design and correlation analysis.…”

Glioma-targeted superparamagnetic iron oxide nanoparticles as drug-carrying vehicles for theranostic effects

“…Recently, several reports have indicated that magnetic nanoparticles combined with an external magnetic field could be used for the transportation of drugs across the BBB30,31 . Seong Deok Kong et al first noticed that magnetic nanoparticles could cross the normal BBB when subjected to an external magnetic field.…”

Nanoparticle corona artefacts derived from specimen preparation of particle suspensions

“…This was diluted in cell culture media to 100 μg/mL, either in DMEM or RPMI, both supplemented with 10% fetal bovine serum (FBS). DMEM and RPMI are common cell culture media formulated from salts, vitamins and amino acids; the two different media contain the same components but differ in the relative concentrations notably of Ca 2+ and PO 4 3− ions 8 . Henceforth, DMEM/RPMI is referred to as cell culture media (CCM) and when supplemented with 10% FBS is referred to as complete cell culture media (CCCM).…”

“…There is increasing evidence and understanding of the potential therapeutic benefits of using nanotechnology within medicine 1,2 . A wide range of nanoparticles have been studied and shown promise in applications such as drug delivery, medical imaging and cancer therapy [3][4][5][6] . Typically such nanomedical studies require nanoparticles to be dispersed in biological fluids.…”