The use of laser-based diagnostics for the rapid identification of infectious agents in human blood

Laser induced breakdown spectroscopy for the rapid detection of SARS-CoV-2 immune response in plasma

As the SARS-CoV-2 pandemic persists, methods that can quickly and reliably confirm infection and immune status is extremely urgently and critically needed. In this contribution we show that combining laser induced breakdown spectroscopy (LIBS) with machine learning can distinguish plasma of donors who previously tested positive for SARS-CoV-2 by RT-PCR from those who did not, with up to 95% accuracy. The samples were also analyzed by LIBS-ICP-MS in tandem mode, implicating a depletion of Zn and Ba in samples of SARS-CoV-2 positive subjects that inversely correlate with CN lines in the LIBS spectra.

The use of laser-based diagnostics for the rapid identification of blood borne viruses in human plasma samples

AIMS

To demonstrate the use of a laser-based method of detection as a potential diagnostic test for the rapid identification of blood borne viruses in human plasma.

METHODS AND RESULTS

In this study, using light emissions from laser sparks on plasma samples, the successful differentiation of both human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in both residual de-identified plasma samples and plasma samples spiked to clinically relevant levels with each virus were demonstrated using plasma from more than 20 individuals spanning six different blood types (O+, O-, A+, A-, B+, B-).

CONCLUSIONS

These experiments demonstrate that mathematical analysis of spectral data from laser sparks can provide accurate results within minutes. This capability was demonstrated using both spiked laboratory plasma samples and clinical plasma samples collected from infected and uninfected individuals.

SIGNIFICANCE AND IMPACT OF THE STUDY

There is an ongoing need to rapidly detect viral infections and to screen for multiple viral infections. A laser-based approach can achieve sensitive, multiplex detection with minimal sample preparation and provide results within minutes. These properties along with the flexibility to add new agent detection by adjusting the detection programming make it a promising tool for clinical diagnosis. The potential for a laser-based approach has been previously demonstrated using pathogens spiked into human blood to clinically relevant levels. This study demonstrates this same ability to detect infections in clinical and laboratory spiked plasma samples. The ability to differentiate between plasma samples from infected and uninfected donors and determine the virus type using a laser-based diagnostic has not been previously demonstrated. Furthermore, this study is the first demonstration of the capability to differentiate viral infections in clinical plasma samples whereas previously published work used laboratory samples spiked with a virus or dealt with the detection of cancer in clinical plasma samples.