Affordable on-site COVID-19 test using non-powered preconcentrator

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Infectious Disease Diagnostics

Background:

• Point-of-care tests (POCTs) are crucial for on-site detection of infectious diseases like COVID-19.
• Lateral flow assays (LFAs) offer advantages in cost and ease of use but often lack the sensitivity needed for early diagnosis.
• Improving the limit of detection (LOD) is essential for sensitive and reliable diagnostic assays.

Purpose of the Study:

• To develop a non-powered preconcentrator (NPP) to enhance the sensitivity of SARS-CoV-2 antigen lateral flow assays.
• To improve the limit of detection (LOD) for early and accurate COVID-19 diagnostics.
• To create an affordable and easy-to-implement diagnostic tool.

Main Methods:

• A non-powered preconcentrator (NPP) was designed using glass fiber-based composite paper and ion permselective material.
• The NPP utilizes nanoelectrokinetics, balancing gravitational, capillary, and depletion-induced forces for sample concentration.
• The method was evaluated for its ability to enrich SARS-CoV-2 viral nucleocapsid (N) proteins and improve LOD in LFAs.

Main Results:

• The NPP successfully enriched SARS-CoV-2 viral nucleocapsid (N) proteins within a 10-minute operation.
• The LOD of the LFA was improved by up to tenfold.
• Virus enrichment showed an improvement in ΔCt values > 3 when evaluated using RT-PCR.

Conclusions:

• The proposed non-powered preconcentrator effectively enhances the sensitivity of SARS-CoV-2 antigen LFAs.
• This NPP-assisted LFA demonstrates potential for affordable, sensitive, and easy-to-implement point-of-care diagnostics.
• The technology was successfully applied to clinical samples, indicating its practical utility.