# Biocompatibility Research of Magnetosomes Synthesized by Acidithiobacillus ferrooxidans

## TL;DR

This study evaluates the biocompatibility of magnetic nanoparticles produced by a specific bacterium, finding them safe and suitable for biomedical applications.

## Contribution

A comprehensive biocompatibility assessment of Fe3O4 magnetosomes synthesized by Acidithiobacillus ferrooxidans is presented.

## Key findings

- Magnetosomes degrade thoroughly in major organs with minimal residue in rats.
- Low toxicity levels were observed at lower injection concentrations.
- Magnetosomes showed low cytotoxicity, genotoxicity, immunotoxicity, and hemolysis rates.

## Abstract

Magnetosomes are magnetic nanocrystals synthesized by bacteria that have important application value in biomedicine. Therefore, it is very important to evaluate their biocompatibility. It has been reported that the extremophilic acidophilic bacterium Acidithiobacillus ferrooxidans, which is aerobic, can synthesize intracellular Fe3O4 magnetosomes. In this paper, we performed a comprehensive and systematic evaluation of the biocompatibility of magnetosomes with an average particle size of 53.66 nm from Acidithiobacillus ferrooxidans, including pharmacokinetics, degradation pathways, acute systemic toxicity, cytotoxicity, genotoxicity, blood index and immunotoxicity. The phase composition of the magnetosomes was identified as Fe3O4 through XRD and HRTEM analyses. Biocompatibility evaluation results showed that magnetosomes metabolized rapidly in rats and degraded thoroughly in major organs, with almost no residue. When the injection concentration was low (40 mg/kg, 60 mg/kg), magnetosomes would not cause pathological changes in the major organs of mice, basically. At the same time, magnetosomes had low cytotoxicity, genotoxicity, immunotoxicity and hemolysis rate, which proved that the magnetosomes synthesized by Acidithiobacillus ferrooxidans are magnetic nanomaterials with good biocompatibility. This research provides an important theoretical basis for the large-scale application of bacterial magnetosomes as functional magnetic nanomaterials.