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

Enhancing Loop-Mediated Isothermal Amplification through Nonpowered Nanoelectric Preconcentration

“…The sample was then introduced to the top of the NPP and allowed to pass through a Nafion membrane patterned on the NPP (see Materials & Methods for detailed fabrication). During this step, the virus particles were enriched on the upper part of Nafion membrane by the balance between gravitational, capillary, and depletion-induced forces 30 (Figure 1b). The preconcentrated upper part (called disc) was sectioned, and the enriched viruses on discs were lysed by loading lysis buffer, releasing the extracted RNA under the centrifugation for subsequent LAMP assay.…”

“…For a comprehensive description of the fabrication process, refer to our previous literature. 30 To operate the NPP device, 400 μL of a patient sample was introduced and allowed to be preconcentrated for 5 min. The concentrated discs were then sectioned and subjected to centrifugation under 10,000 rpm for 10 min which yielded ∼40 to 50 μL of enriched samples.…”

“…After the Nafion resin was applied and dried, the paper was manually configured into a roll-shaped and securely sealed with transparent tape (3 M Scotch, USA). For a comprehensive description of the fabrication process, refer to our previous literature . To operate the NPP device, 400 μL of a patient sample was introduced and allowed to be preconcentrated for 5 min.…”

Recent advances in point-of-care testing of COVID-19

“…Antigen LFAs have been successfully utilized for the diagnosis of COVID-19. 20,21 These assays are particularly effective in detecting antigens at high concentrations in human specimens, facilitating prompt confirmation of COVID-19. Fig.…”

Immunochromatographic enhancement strategy for SARS-CoV-2 detection based on nanotechnology

“…Sample enrichment techniques have attracted considerable attention from researchers for improving the sensitivity and reducing the LOD. A powerless pre-concentrator for the detection of SARS-CoV-2 was developed by Kim et al 68 The pre-concentrator comprised glass fiber-based composite paper and an ion permeation selective material, which achieved sample enrichment by balancing gravity, capillary forces, and depletion-induced forces without the need for an external power source. The proposed method facilitated the enrichment of SARS-CoV-2 N protein within 10 min and reduced the LOD by a factor of 10.…”