bims-mricoa Biomed News
on MRI contrast agents
Issue of 2022‒05‒29
four papers selected by
Merve Yavuz
Bilkent University

  1. Pharmaceutics. 2022 Apr 26. pii: 937. [Epub ahead of print]14(5):
      Cancer is among the leading causes of mortality globally, with nearly 10 million deaths in 2020. The emergence of nanotechnology has revolutionised treatment strategies in medicine, with rigorous research focusing on designing multi-functional nanoparticles (NPs) that are biocompatible, non-toxic, and target-specific. Iron-oxide-based NPs have been successfully employed in theranostics as imaging agents and drug delivery vehicles for anti-cancer treatment. Substituted iron-oxides (MFe2O4) have emerged as potential nanocarriers due to their unique and attractive properties such as size and magnetic tunability, ease of synthesis, and manipulatable properties. Current research explores their potential use in hyperthermia and as drug delivery vehicles for cancer therapy. Significantly, there are considerations in applying iron-oxide-based NPs for enhanced biocompatibility, biodegradability, colloidal stability, lowered toxicity, and more efficient and targeted delivery. This review covers iron-oxide-based NPs in cancer therapy, focusing on recent research advances in the use of ferrites. Methods for the synthesis of cubic spinel ferrites and the requirements for their considerations as potential nanocarriers in cancer therapy are discussed. The review highlights surface modifications, where functionalisation with specific biomolecules can deliver better efficiency. Finally, the challenges and solutions for the use of ferrites in cancer therapy are summarised.
    Keywords:  biocompatibility; cancer therapy; ferrites; functionalisation; magnetic nanoparticles
  2. Int J Mol Sci. 2022 May 16. pii: 5554. [Epub ahead of print]23(10):
      Biomineralization is an elaborate process that controls the deposition of inorganic materials in living organisms with the aid of associated proteins. Magnetotactic bacteria mineralize magnetite (Fe3O4) nanoparticles with finely tuned morphologies in their cells. Mms6, a magnetosome membrane specific (Mms) protein isolated from the surfaces of bacterial magnetite nanoparticles, plays an important role in regulating the magnetite crystal morphology. Although the binding ability of Mms6 to magnetite nanoparticles has been speculated, the interactions between Mms6 and magnetite crystals have not been elucidated thus far. Here, we show a direct adsorption ability of Mms6 on magnetite nanoparticles in vitro. An adsorption isotherm indicates that Mms6 has a high adsorption affinity (Kd = 9.52 µM) to magnetite nanoparticles. In addition, Mms6 also demonstrated adsorption on other inorganic nanoparticles such as titanium oxide, zinc oxide, and hydroxyapatite. Therefore, Mms6 can potentially be utilized for the bioconjugation of functional proteins to inorganic material surfaces to modulate inorganic nanoparticles for biomedical and medicinal applications.
    Keywords:  biomineralization; magnetotactic bacteria; metal oxide; nanoparticle; protein adsorption
  3. Colloids Surf B Biointerfaces. 2022 May 11. pii: S0927-7765(22)00239-9. [Epub ahead of print]216 112556
      Magnetosomes intracellularly biomineralized by Magnetotactic bacteria (MTB) are membrane-enveloped nanoparticles of the magnetic minerals magnetite (Fe3O4) or greigite (Fe3S4). MTB thrive in oxic-anoxic interface and exhibit magnetotaxis due to the presence of magnetosomes. Because of the unique characteristic and bionavigation inspiration of magnetosomes, MTB has been a subject of study focused on by biologists, medical pharmacologists, geologists, and physicists since the discovery. We herein first briefly review the features of MTB and magnetosomes. The recent insights into the process and mechanism for magnetosome biomineralization including iron uptake, magnetosome membrane invagination, iron mineralization and magnetosome chain assembly are summarized in detail. Additionally, the current research progress in biotechnological applications of magnetosomes is also elucidated, such as drug delivery, MRI image contrast, magnetic hyperthermia, wastewater treatment, and cell separation. This review would expand our understanding of biomineralization and biotechnological applications of bacterial magnetosomes.
    Keywords:  Biomineralization; Biotechnological application; Iron uptake; Magnetosome; Magnetotactic bacteria