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Magnetic relaxation switching biosensor via polydopamine nanoparticle mediated click chemistry for detection of chlorpyrifos.
- Source :
-
Biosensors & bioelectronics [Biosens Bioelectron] 2022 Jul 01; Vol. 207, pp. 114127. Date of Electronic Publication: 2022 Feb 26. - Publication Year :
- 2022
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Abstract
- Traditional magnetic relaxation switching (MRS) biosensors suffer from poor sensitivity and unsatisfactory stability. In this study, a polydopamine (PDA) nanoparticles (NPs)-Cu <superscript>2+</superscript> chelate complex mediated signal conversion system and a Cu <superscript>+</superscript> -catalyzed click chemistry triggered magnetic signal amplification system were evaluated and dynamically integrated into an MRS biosensor. Owing to abundant functional groups and a large surface area, PDA NPs enabled the absorption of a large amount of Cu <superscript>2+</superscript> ions by chelation. The residual Cu <superscript>2+</superscript> ions can be reduced with sodium ascorbate to Cu <superscript>+</superscript> , which could initiate the click reaction between azide-functionalized magnetic NPs (MNPs) and alkyne-functionalized MNPs that resulted in the production of aggregated nanoclusters. The transverse relaxation time (T <subscript>2</subscript> ) depends on the degree of aggregation of MNPs; T <subscript>2</subscript> is expressed as the magnetic signal readout. In addition, PDA NPs can be easily conjugated with antibodies by mixing, thus providing a straightforward bridge that integrates the immunoassay and magnetic signal readout. Combined with the high capacity of PDA NPs for chelating Cu <superscript>2+</superscript> and high efficiency of click reaction for changing the T <subscript>2</subscript> signals, the PDA-MRS biosensor enables the detection of chlorpyrifos with a limit of detection of 0.084 ng/mL, providing 22-fold enhancement than traditional enzyme-linked immunosorbent assay (1.86 ng/mL). This demonstrates its great potential for the detection of hazardous chemical molecules in a complex sample matrix.<br /> (Copyright © 2022 Elsevier B.V. All rights reserved.)
Details
- Language :
- English
- ISSN :
- 1873-4235
- Volume :
- 207
- Database :
- MEDLINE
- Journal :
- Biosensors & bioelectronics
- Publication Type :
- Academic Journal
- Accession number :
- 35278785
- Full Text :
- https://doi.org/10.1016/j.bios.2022.114127