Sustainable Electrochemical-Magnetic Biosensor Fabricated from Recycled Materials for Label-Free Detection of SARS-CoV-2 in Human Saliva

Author(s):Show less -

Carvalho, Caio Lenon Chaves ; Nascimento, Steffane Q. ; Bertaglia, Thiago ; Faria, Luana C. I. ; Manuli, Erika R. ; Pereira, Geovana M. ; da Silva, Welter Cantanhede ; Costa, Carlos M. ; Maestu, Josu Fernandez ; Lanceros-Mendez, Senentxu ; Oliveira Jr, Osvaldo N. ; Sabino, Ester C. ; Crespilho, Frank N.

• Document type: Journal article
• Source: ACS SENSORS; v. 10, n. 3, p. 16-pg., 2025-03-14.

Abstract

The COVID-19 pandemic has highlighted the critical need for scalable, rapid, and cost-effective diagnostic solutions, especially in resource-limited settings. In this study, we developed a sustainable magnetic electrochemical biosensor for the mass testing of SARS-CoV-2, emphasizing affordability, environmental impact reduction, and clinical applicability. By leveraging recycled materials from spent batteries and plastics, we achieved a circular economy-based fabrication process with a recyclability rate of 98.5%. The biosensor employs MnFe2O4 nanoparticles functionalized with anti-SARS-CoV-2 antibodies, integrated into a 3D-printed electrochemical device for decentralized testing. Advanced characterization confirmed the biosensor's robust performance, including high sensitivity (LOD: 3.46 pg mL-1) and specificity, with results demonstrating a 95% correlation to RT-PCR gold standard testing. The cost of materials used per biosensor test is only USD 0.2, making it highly affordable and suitable for large-scale production using additive manufacturing. Key features include simple preparation, rapid response, and reusability, making it ideal for point-of-care diagnostics. Beyond COVID-19, this platform's modularity allows for adaptation to other viral diseases, offering a versatile solution to global diagnostic challenges. This work highlights the potential of integrating electrochemical sensing with sustainable practices to address healthcare inequities and reduce environmental impact. (AU)

• FAPESP's process: 22/09164-5 - Understanding the charge transfer mechanisms in biological and biomimetic systems using in-situ and operando techniques: from fundamental science to energy application
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/03681-2 - Organic microbatteries: using bioinspired hydrogels and redox molecules
• Grantee: Thiago Bertaglia
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 23/13288-4 - Development of Electrochemical Nanodevices
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 19/15333-1 - Bio-photo-electrochemical hybrid cells for solar energy conversion
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/12053-8 - High performance electrodes applied in organic batteries and in biofuel cell
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants