Use of bacterial magnetosomes in the magnetic hyperthermia treatment of tumours: A review

Abstract

We review the most recent and significant results published in the field of magnetotactic bacteria (MTB), in particular data relating to the use of bacterial magnetosomes in magnetic hyperthermia for the treatment of tumours. We review different methods for cultivating MTB and preparing suspensions of bacterial magnetosomes. As well as the production of magnetosomes, we also review key data on the toxicity of the magnetosomes as well as their heating and anti-tumour efficiencies. The toxicity and efficiency of magnetosomes needs to be understood and the risk-benefit ratio with which to evaluate their use in the magnetic hyperthermia treatment of tumours needs to be measured.

Characterization of magnetic nanoparticles from Magnetospirillum Gryphiswaldense as potential theranostics tools

“…In particular, we showthattheMNsactaseffectivehyperthermiamediatorswhenexposedtoalternatingmagneticfieldsofanamplitudeof17kA/mand frequency183 kHz,andasMRInegativecontrastagentsattheclinical fields0.2 Tand1.5 Tbothinvitroandinvivo (8,(12)(13)(14).TheMRIcontrast efficiency has been established by collecting, for the first time to our knowledge, the complete NMR-dispersion profiles of longitudinal and transverserelaxivities.…”

Nanoprobe Synthesized by Magnetotactic Bacteria, Detecting Fluorescence Variations under Dissociation of Rhodamine B from Magnetosomes following Temperature, pH Changes, or the Application of Radiation

“…With these probes, it is possible to detect locally a wide range of 4 hyperthermia and magnetic resonance imaging 28,29,30 . Fabrication of fluorescent magnetosomes were previously described, either involving genetic manipulations of magnetotactic bacteria to produce magnetosomes tagged with green fluorescent proteins 31,32 , or a chemical hydrophobic interaction between a fluorophore (DiI) and magnetosomes extracted from magnetotactic bacteria 33 .…”

Synthesis, Functionalization, and Design of Magnetic Nanoparticles for Theranostic Applications

“…[278] Surprisingly, there are several species of MTB that can be cultivated in vitro under conditions where growth and magnetite biomineralization are optimized to collect their biomineralized magnetosome for biological applications. [279] A series of three publications have described the optimization of the growth of the most popular type of MTB, Magnetospirillum gryphiswaldense MSR-1, to enable industrial developments required for the large production of magnetosomes. [280] As it was mentioned, MTB exploit the alignment of magnetosomes to migrate into zones where oxygen and other redox active compounds are horizontally stratified.…”

“…[285] After cultivation of MTB, mature magnetosomes are extracted from the MTB through methods which use sodium hydroxide (NaOH), sonication, a French press, or a pressure homogenizer to lyse the bacterial cells. [279] Subsequently, magnetosomes are purified, most commonly by using a system of magnetic isolation which is followed by low power ultrasonication and a proper treatment with proteins K and electro-elution to remove adsorbed and surface proteins as nucleic acids. [286] …”