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Updated: Jul 27, 2026
High-throughput Detection Method for Influenza Virus
Published on: February 4, 2012
Cellulose test strips modified with virus-like particles: Advancing viral immunity screening technologies
Claudia Pereira1, Cristina E A Sousa2, Daniela Mateus3
1CIETI - LabRISE-School of Engineering, Polytechnic of Porto, R. Dr. António Bernardino de Almeida, 431 4249-015 Porto, Portugal; HE-FP-Hospital Fernando Pessoa, CECLIN-Center of Clinical Studies 4420-096 Gondomar, Portugal; FP-I3ID-Instituto de Investigação, Inovação e Desenvolvimento, FP-BHS-Biomedical and Health Sciences, Portugal; FCS-Faculty of Health Sciences, Fernando Pessoa University 4249-004 Porto, Portugal; I3S-Instituto de Investigação e Inovação em Saúde 4200-135 Porto, Portugal.
A new colorimetric biosensor detects COVID-19 immunity by identifying SARS-CoV-2 antibodies. This rapid, sensitive test using virus-like particles on cellulose shows promise for global health screening.
Area of Science:
- Biomedical Engineering
- Immunology
- Materials Science
Background:
- The COVID-19 pandemic spurred widespread immunity via infection and vaccination, necessitating reliable antibody detection methods.
- Existing diagnostic tools vary in accessibility and speed, highlighting the need for innovative screening solutions.
Purpose of the Study:
- To develop and validate a novel colorimetric biosensor for detecting SARS-CoV-2 antibodies, indicating COVID-19 immunity.
- To assess the biosensor's sensitivity, selectivity, and potential for clinical application.
Main Methods:
- Chemically modified cellulose carriers immobilized SARS-CoV-2 spike protein motifs on virus-like particles (VLPs).
- Detection was performed using the Bradford reagent, with results analyzed via RGB colorimetry using ImageJ and smartphone imaging.
- Fourier-transform infrared spectroscopy (FTIR) confirmed VLP immobilization.
Main Results:
- The biosensor demonstrated high sensitivity with a correlation coefficient (R) > 0.998 over a 10-40 µg/mL antibody concentration range.
- Effective detection was achieved in both buffer and serum samples within a 30-minute incubation period.
- The biosensor showed excellent selectivity, unaffected by common biological interferents like albumin, glucose, and urea.
Conclusions:
- The developed colorimetric biosensor offers a sensitive, selective, and rapid method for assessing COVID-19 immunity.
- Its performance with undiluted samples and REASSURED compliance indicate significant potential for widespread global diagnostic applications.
