New test to detect respiratory infections

A team from the Universitat Politècnica de València (UPV), coordinated by Professor Ángel Maquieira, belonging to the Institute of Molecular Recognition and Technological Development (IDM), has developed a new test based on compact disc technology, which allows the rapid, simple, and low-cost detection of up to five different respiratory infections, specifically: COVID-19, Influenza A, Influenza B, Adenovirus, Respiratory Syncytial Virus (RSV).

The work has been published in the journal Biosensors and Bioelectronics, and it involves researchers from the departments of Microbiology and Chemistry-Physics of the University of Valencia and the Microbiology Service of the Hospital Clínic Universitari de València, under the direction of Dr David Navarro, principal investigator of the Research Group in Molecular Microbiology and Microbial Pathogenesis of INCLIVA.

The biosensing test system consists of a transparent microperforated disc with microfluidic structures on which the samples to be analysed are placed and a DVD-type compact disc reader adapted with technology developed by the UPV research group. "When a person tests positive, the sample generates an optical signal, which the reader interprets and determines whether the patient is infected or not and what pathology he or she is suffering from," explains Sergi Morais, professor in the Department of Chemistry and researcher at the IDM Institute of the Polytechnic University of Valencia and one of the creators of the test.

The device devised by the UPV team can simultaneously detect both viral antigens in nasopharyngeal swab samples and the presence of specific antiviral antibodies in human serum samples. Also, it can analyse up to six samples simultaneously, in 30 minutes, at a reduced cost - the researchers estimate €1/sample.

"The main advantage of this system is the possibility to simultaneously identify and discriminate several respiratory diseases in a single assay. Both nasopharyngeal and human serum samples can be tested in a single device. And it offers fast and reliable results at a lower cost. All this makes it an attractive solution for implementation at health care units," says Ángel Maquieira.

In addition, another feature that differentiates this prototype device from others on the market is its versatility, as it would be able to detect new variants of interest, and other microorganisms, that occur in the same period of the year. "This multiple and rapid detection has not been reported, so far, by any other type of rapid test device," says William Teixeira, a researcher at IDM and another of the test's developers.

Validated at the Hospital Clínic Universitari de València and at the UPV

To obtain actual samples, the IDM-UPV team collaborated with the Hospital Clínic Universitari de València and the Juana Portaceli Occupational Health Centre of the UPV. They analysed 287 actual samples from individuals suspected of having COVID-19, both symptomatic and asymptomatic. Validation was performed by comparison with commercially established methods, either rapid antigen detection with test strips or antibody detection by ELISA assays.

"An excellent level of concordance of results has been observed in all cases. 100% of the samples that tested positive for the strip test (Abbott) were also detected as positive by our biosensor. In the case of COVID-19, the predictive capacity of the assays for positive and negative results is, respectively, 88% and 98% for the serological test, and 95% and 100% for the antigen test," explains Sergi Morais.

Suitable for mass testing

The device has great potential for mass testing and is especially useful for population screening management. It can be used in crowded places such as airports, schools, hospitals or sports stadiums.

In addition, the solution's versatility means that the device could be used in future health emergencies due to epidemics or pandemics, as it can integrate other new viruses or strains of interest. "It can even be used to evaluate the effectiveness of vaccination of the population, as it can also analyse the antibodies of people who have already suffered or are suffering from one of these diseases," adds Teixeira.

Awarded by the Spanish Royal Society of Chemistry (RSEQ)

The team from the IDM Institute of the Universitat Politècnica de València presented this device at the XXXVIII Biennial Meeting of the Spanish Royal Society of Chemistry (RSEQ), held in Granada last June. His research was awarded the prize for the best paper in the area of biosensors, granted by the company LASING S.A. and the group specialising in Science and (Bio)Analytical Technologies (GCT(b)A) of the RSEQ.

They also presented it at the latest edition of the International Workshop on Sensors and Molecular Recognition 2022 IWOSMOR, which took place in mid-July at the Universitat Politècnica de València.

Reference

An all-in-one point-of-care testing device for multiplexed detection of respiratory infections. William Teixeira, Yeray Pallás-Tamarit, Augusto Juste-Dolz, Amadeo Sena-Torralba, Roberto Gozalbo-Rovira, Jesús Rodríguez-Díaz, David Navarro, Javier Carrascosa, David Gimenez-Romero, Ángel Maquieira, Sergi Morais. Biosensors and Bioelectronics 213 (2022) 114454, ISSN: 0956-5663. https://doi.org/10.1016/j.bios.2022.114454.