Bioapplications of Magnetic Nanowires: Barcodes, Biocomposites, Heaters

Abstract

Magnetic nanowires (MNWs) can have their moments reversed via several mechanisms that are controlled using the composition, length, diameter, and density of nanowires in arrays as-synthesized or as individual nanoparticles in assays or gels. This tailoring of magnetic reversal leads to unique properties that can be used as a signature for reading out the type of MNW for applications as nano-barcodes. When synthesized inside track etched polycarbonate membranes, the resulting MNW-embedded membranes can be used as biocompatible bandaids for detection without contact or optical sighting. When etched out of the growth template, free-floating MNWs are internalized by cells at 37ºC, such that cells and/or exosomes can be collected and detected. In applications of cryopreservation, MNWs can be suspended in cryopreservation agents for injection into the blood vessels of tissues and organs as they are vitrified to -200ºC. Using an alternating magnetic field, the MNWs can then be nanowarmed rapidly to prevent crystallization and uniformly to prevent cracking of specimens, for example as grafts or transplants. This invited paper is a review of recent progress in the specific bioapplications of MNWs to barcodes, biocomposites, and nanowarmers.

Special Issue: Ceramic and Metallic Biomaterials Nanoparticles for Applications in Medical Sciences

“…Another important property that makes this type of material suitable to be used in bio-medicine is that magnetic nanomaterials can be heated by an applied magnetic field. Thus, the data presented in the literature show that magnetic nanoparticles can be used to transport drugs in the body, for the treatment of cancer (by hyperthermia or magneto-mechanical effect), and as contrast agents for cancer cell visualization [10][11][12], etc.…”