Rapid Quantum Magnetic IL-6 Point-of-Care Assay in Patients Hospitalized with COVID-19

Abstract

Interleukin-6 (IL-6) has been linked to several life-threatening disease processes. Developing a point-of-care testing platform for the immediate and accurate detection of IL-6 concentrations could present a valuable tool for improving clinical management in patients with IL-6-mediated diseases. Drawing on an available biobank of samples from 35 patients hospitalized with COVID-19, a novel quantum-magnetic sensing platform is used to determine plasma IL-6 concentrations. A strong correlation was observed between IL-6 levels measured by QDTI10x and the Luminex assay (r = 0.70, p-value < 0.001) and between QDTI80x and Luminex (r = 0.82, p-value < 0.001). To validate the non-inferiority of QDTI to Luminex in terms of the accuracy of IL-6 measurement, two clinical parameters—the need for intensive care unit admission and the need for mechanical intubation—were chosen. IL-6 concentrations measured by the two assays were compared with respect to these clinical outcomes. Results demonstrated a comparative predictive performance between the two assays with a significant correlation coefficient. Conclusion: In short, the QDTI assay holds promise for implementation as a potential tool for rapid clinical decision in patients with IL-6-mediated diseases. It could also reduce healthcare costs and enable the development of future various biomolecule point-of-care tests for different clinical scenarios.

Quantum sensors for biomedical applications

“…In another demonstration, NV-based magnetic microscopy was applied to detect concentrations of magnetically labelled protein, interleukin-6 65 , from patients hospitalized with COVID-19. Interleukin-6 is an endogenous cytokine associated with various diseases, such as severe COVID-19.…”

Digital detection of proteins

“…Spatial isolation of labels Detection of many single labels Enzymes confined in wells 8 or droplets 76 Microwell arrays 55,140 Wide FOV, high resolution multi-wavelength imaging 69 Amplification of nucleic acid labels in droplets 64 Arrays of droplets 77 Flow combined with laser-induced fluorescence 43 Labels directly associated with beads 60,63 Flow of droplets 59 Electrical 126 Nanoparticles 33, 103 Random dispersed arrays 62 Wide FOV plasmonic imaging 104 DNA nanostructures 127 Nanopore arrays 126 Scatter imaging 119 Laser induced fluorescence of bound labels 39 Flow cytometry 60 Coincidence detection 113 Laser induced fluorescence of released labels 42 Nanostructured surfaces 135 Time-resolved fluorescence (TIRF) microscopy 37 Particle motion 119,120 Mass spectrometry 142 Differential kinetics of specifically bound labels 123 Transmission electron microscopy 113 Nanopore blockade 125 Surface plasmon imaging 123 Nanopore translocation 127 Microbubbles 137 Diamond nitrogen vacancy centers 141 digital droplet immuno-PCR (ddIPCR). They formed oligonucleotide-labeled immunocomplexes at the surface of an ELISA plate, chemically released the label from the surface, partitioned the labels into droplets using a commercial droplet generator, performed PCR on the droplets, and then analyzed the on/off status of the droplets using a commercial droplet reader.…”

“…For example, Wang et al 139 and Piraino et al 140 have used pneumatic sealing of PDMS microwell arrays against glass surfaces in integrated microfluidic devices to digitize immunocomplexes formed on planar surfaces. Atallah et al 141 reported the detection of single immunocomplexes using diamond nitrogen vacancy centers, where two different magnetic bead labels on the antibodies that respond differently to the magnetic field can, therefore, make use of coincidence optical detection. They used this approach to develop an assay for IL-6 with an LOD of 2 fM to measure the protein in the serum of COVID-19 patients.…”

Atomic-precise Pt2Cu4 cluster-based fluorescent sensor for rapid interleukin-6 detection

“…As an endogenous cytokine, interleukin-6 (IL-6) has been linked to many inammatory diseases, such as chronic obstructive pulmonary disease. 1,2 The detection of IL-6 in serum plays a signicant role in disease diagnosis and prognosis. [3][4][5] Therefore, the development of sensors for the rapid and accurate detection of IL-6 has great signicance.…”