One-step immobilization of antibodies and DNA on gold sensor surfaces via a poly-adenine oligonucleotide approach
Huertas, César S. (Institut Català de Nanociència i Nanotecnologia)
Soler Aznar, Maria (Institut Català de Nanociència i Nanotecnologia)
Estévez, M. Carmen (Institut Català de Nanociència i Nanotecnologia)
Lechuga, Laura M (Institut Català de Nanociència i Nanotecnologia)

Date:	2020
Abstract:	Label-free plasmonic biosensors have demonstrated promising capabilities as analytical tools for the detection of virtually any type of biomarker. They are presented as good candidates for precision diagnostics since they offer highly sensitive, cost-effective solutions that can be used in any clinical or laboratory setting without the need for specialized trainees. However, different surface functionalization protocols are required, depending on the nature of the biorecognition element, limiting their capabilities for integrated multi-biomarker detection. Here, we present a simple, yet efficient, one-step immobilization approach that is common for both DNA probes and antibodies. Our immobilization approach relies on the incorporation of poly-adenine (polyA) blocks in both nucleic acid probes and antibodies. PolyA sequences have a remarkable affinity for gold surfaces and can specifically interact with sufficient strength to generate stable, dense, and highly ordered monolayers. We have demonstrated excellent performance of our universal functionalization method, showing limits of detection and quantification in the pM-nM range. Moreover, it was able to reduce up to 50% of the background signal from undiluted serum samples compared to conventional methods, demonstrating the immense potential of this strategy for the direct analysis of human biofluids, essential for rapid point-of-care diagnostics. The polyA-based immobilization approach is a promising alternative for the generation of multiplexed biosensors that can detect both protein and nucleic acid biomarkers for multiparametric diagnostic assays.
Grants:	Ministerio de Ciencia e Innovación FICTS-1420-27 Ministerio de Ciencia e Innovación SEV-2017-0706
Note:	Altres ajuts: C.S.H. is a recipient of an RMIT Vice Chancellor's Postdoctoral Fellowship.
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió sotmesa a revisió
Subject:	Background signals ; Biorecognition elements ; Conventional methods ; Cost-effective solutions ; Limits of detection ; Plasmonic biosensors ; Point of care diagnostic ; Surface Functionalization
Published in:	Analytical chemistry, Vol. 92, issue 18 (Sep. 2020) , p. 12596-12604, ISSN 1520-6882

DOI: 10.1021/acs.analchem.0c02619

Preprint 10 p, 766.1 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
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