Magnetic nanowires (MNWs) rank among the most promising multifunctional magnetic nanomaterials for nanobarcoding applications, especially biolabeling, owing to their nontoxicity and remote excitation using a single magnetic source. Until recently, the first-order reversal curve (FORC) technique has been broadly used to study the MNWs for biolabeling applications. However, since FORC measurements require many data points, this technique is very slow which makes it inapplicable for clinical use. For this reason, we recently developed a fast new framework, named the projection method, to measure the irreversible switching field (ISF) distributions of MNWs as the magnetic signature for the demultiplexing of magnetic biopolymers. Here, we illustrate the ISF distributions of several MNWs types in terms of their coercivity and interaction fields, which are characterized using both FORC and projection methods. Then, we explain how to tailor the ISF distributions to generate distinct signature to reliably and quantitatively demultiplex the magnetically enriched biopolymers.
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Projection method as a probe for multiplexing/demultiplexing of magnetically enriched biological tissues
The unmet demand for cheap, accurate, and fast multiplexing of biomarkers has urged nanobiotechnology to prioritize the invention of new biomarkers that make feasible the remote detection, identification, and quantification of biological units, such as regenerative tissues. Here, we introduce a novel approach that highlights magnetic nanowires (MNWs) with such capabilities. This method employs the stable magnetization states of MNWs as a unique characteristic that can be realized by projecting the MNWs' switching field on the backward field ( P Hb ), also known as the irreversible switching field. Experimentally, several types of MNWs were directly synthesized inside polycarbonate tissues and their P Hb characteristics were measured and analyzed. Our results show that the P Hb gives an excellent identification and quantification characteristic for demultiplexing MNWs embedded in these tissues. Furthermore, this method significantly improves the characterization speed by a factor of 50×–100× that makes it superior to the current state of the art that ceased the progression of magnetic nanoparticles in multiplexing/demultiplexing applications.
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- Award ID(s):
- 1642268
- PAR ID:
- 10209704
- Date Published:
- Journal Name:
- RSC Advances
- Volume:
- 10
- Issue:
- 22
- ISSN:
- 2046-2069
- Page Range / eLocation ID:
- 13286 to 13292
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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