Integration of sample preparation with RNA-Amplification in a hand-held device for airborne virus detection

A Valve-Enabled Sample Preparation Device with Isothermal Amplification for Multiplexed Virus Detection at the Point-of-Care

“…An untreated cellulose chromatography paper was chosen for RNA enrichment because it has shown better results for RNA enrichment of influenza viruses when compared with the glass-fiber paper and FTA card. 17 Additionally, the device does not require an elution step as in the QIAGEN kit, where the purified RNA needs to be eluted before amplification, which has significant disadvantages: (1) the purified RNA is diluted during elution and (2) not all the RNA on the column can be eluted. Involving no RNA transfer between tubes as in the lab operation, this device avoids possible contamination and degradation issues.…”

“…Figure 2 d shows the calibration curve between the threshold time and the influenza A virus amount, indicating that semiquantitative detection is feasible as shown previously. 17 Note that the threshold time was automatically reported from the real-time PCR machine.…”

“…An untreated cellulose chromatography paper was chosen for RNA enrichment because it has shown better results for RNA enrichment of influenza viruses when compared with the glass-fiber paper and FTA card. 17 Additionally, the device does not require an elution step as in the QIAGEN kit, where the purified RNA needs to be eluted before amplification, which has significant disadvantages:…”

“…The RNA enrichment process is driven by the capillary forces generated by the chromatography paper in the detection units, eliminating the need of external equipment. An untreated cellulose chromatography paper was chosen for RNA enrichment because it has shown better results for RNA enrichment of influenza viruses when compared with the glass-fiber paper and FTA card . Additionally, the device does not require an elution step as in the QIAGEN kit, where the purified RNA needs to be eluted before amplification, which has significant disadvantages: (1) the purified RNA is diluted during elution and (2) not all the RNA on the column can be eluted.…”

“…The Lucira kit combines RT-LAMP with colorimetric detection, while the Cue test employs an unspecified isothermal amplification followed by electrochemical detection. Many POC testing platforms have been reported for influenza virus detection, including RT-LAMP devices, − microfluidics-based RT-PCR, and other nucleic acid isothermal amplification assays . Similarly, POC platforms for SARS-CoV-2 detection have been developed to incorporate RT-PCR, RT-LAMP, ,, other amplification methods, , and those combined with CRISPR. − …”