Smartphone screen testing, a novel pre-diagnostic method to identify SARS-CoV-2 infectious individuals

Young, Rodrigo; Solis, Camila J; Barriga-Fehrman, Andres; Abogabir, Carlos; Thadani, A.; Labarca, Mariana; Bustamante, Eva; Tapia, Cecilia; Sarda, Antonia G; Sepúlveda, Francisca; Pozas, Nadia; Cerpa, Leslie C.; Lavanderos, María A; Varela, Nelson; Santibáñez, Álvaro; Sandino, Ana María; Reyes-López, Felipe E.; Dixon, Garth; Quiñones, Luis A.

doi:10.7554/elife.70333

Cited by 9 publications

(6 citation statements)

References 42 publications

(62 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We envision that this approach, with proper safety precautions, could be used for home-based testing, as demonstrated by others. 3 , 4 , 19 , 21 The portable multiplexing detection prototype was built with two wavelengths in the optical system: a LED working at 490/26 nm excitation for FITC, and a second LED working at 625/17 nm with the same length of impulse for Cy5 excitation. A combination of reporter pairs could be used for this portable device such as SYTO TM 62 using Cy5 channel for tracking amplification and FRET-based FAM reporter using the FITC channel for detection of BrCas12b trans-cleavage activity, or the SYTO TM 9 and Cy5 reporter pair for the opposite channels.…”

Section: Resultsmentioning

confidence: 99%

A thermostable Cas12b from Brevibacillus leverages one-pot discrimination of SARS-CoV-2 variants of concern

et al. 2022

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 99%

A thermostable Cas12b from Brevibacillus leverages one-pot discrimination of SARS-CoV-2 variants of concern

et al. 2022

View full text Add to dashboard Cite

“…Therefore, saliva is a highly desirable specimen, which can also be easily collected. Young et al [39] demonstrated that smartphone screen swab samples could also be used for detecting positive individuals.…”

Section: Discussionmentioning

confidence: 99%

Robust Saliva-Based RNA Extraction-Free One-Step Nucleic Acid Amplification Test for Mass SARS-CoV-2 Monitoring

et al. 2021

View full text Add to dashboard Cite

Early diagnosis with rapid detection of the virus plays a key role in preventing the spread of infection and in treating patients effectively. In order to address the need for a straightforward detection of SARS-CoV-2 infection and assessment of viral spread, we developed rapid, sensitive, extraction-free one-step reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and reverse transcription loop-mediated isothermal amplification (RT-LAMP) tests for detecting SARS-CoV-2 in saliva. We analyzed over 700 matched pairs of saliva and nasopharyngeal swab (NSB) specimens from asymptomatic and symptomatic individuals. Saliva, as either an oral cavity swab or passive drool, was collected in an RNA stabilization buffer. The stabilized saliva specimens were heat-treated and directly analyzed without RNA extraction. The diagnostic sensitivity of saliva-based RT-qPCR was at least 95% in individuals with subclinical infection and outperformed RT-LAMP, which had at least 70% sensitivity when compared to NSBs analyzed with a clinical RT-qPCR test. The diagnostic sensitivity for passive drool saliva was higher than that of oral cavity swab specimens (95% and 87%, respectively). A rapid, sensitive one-step extraction-free RT-qPCR test for detecting SARS-CoV-2 in passive drool saliva is operationally simple and can be easily implemented using existing testing sites, thus allowing high-throughput, rapid, and repeated testing of large populations. Furthermore, saliva testing is adequate to detect individuals in an asymptomatic screening program and can help improve voluntary screening compliance for those individuals averse to various forms of nasal collections.

show abstract

“…2f). We envision that this approach, with proper safety precautions, could be used for home-based testing, as demonstrated by others 3,4,13,20 . The portable multiplexing detection prototype was built with two wavelengths in the optical system: a LED working at 490/26 nm excitation for FITC, and a second LED working at 625/17 nm with the same length of impulse for Cy5 excitation.…”

Section: Mainmentioning

confidence: 90%

A Thermostable Cas12b fromBrevibacillusLeverages One-pot Detection of SARS-CoV-2 Variants of Concern

Nguyễn

Macaluso

Pizzano

et al. 2021

Preprint

View full text Add to dashboard Cite

Current SARS-CoV-2 detection platforms lack the ability to differentiate among variants of concern (VOCs) in an efficient manner. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) has the potential to transform diagnostics due to its programmability. However, many of the CRISPR-based detection methods are reliant on either a multi-step process involving amplification or elaborate guide RNA designs. A complete one-pot detection reaction using alternative Cas effector endonucleases has been proposed to overcome these challenges. Yet, current approaches using Alicyclobacillus acidiphilus Cas12b (AapCas12b) are limited by its thermal instability at optimum reverse transcription loop-mediated isothermal amplification (RT-LAMP) reaction temperatures. Herein, we demonstrate that a novel Cas12b from Brevibacillus sp. SYP-B805 (referred to as BrCas12b) has robust trans-cleavage activity at ideal RT-LAMP conditions. A competitive profiling study of BrCas12b against Cas12b homologs from other bacteria genera underscores the potential of BrCas12b in the development of new diagnostics. As a proof-of-concept, we incorporated BrCas12b into an RT-LAMP-mediated one-pot reaction system, coined CRISPR-SPADE (CRISPR Single Pot Assay for Detecting Emerging VOCs) to enable rapid, differential detection of SARS-CoV-2 VOCs, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2) in 205 clinical samples. Notably, a BrCas12b detection signal was observed within 1-3 minutes of amplification, achieving an overall 98.1% specificity, 91.2% accuracy, and 88.1% sensitivity within 30 minutes. Significantly, for samples with high viral load (Ct value ≤ 30), 100% accuracy and sensitivity were attained. To facilitate dissemination and global implementation of the assay, we combined the lyophilized one-pot reagents with a portable multiplexing device capable of interpreting fluorescence signals at a fraction of the cost of a qPCR system. With relaxed design requirements, one-pot detection, and simple instrumentation, this assay has the capability to advance future diagnostics.

show abstract

Smartphone screen testing, a novel pre-diagnostic method to identify SARS-CoV-2 infectious individuals

Cited by 9 publications

References 42 publications

A thermostable Cas12b from Brevibacillus leverages one-pot discrimination of SARS-CoV-2 variants of concern

A thermostable Cas12b from Brevibacillus leverages one-pot discrimination of SARS-CoV-2 variants of concern

Robust Saliva-Based RNA Extraction-Free One-Step Nucleic Acid Amplification Test for Mass SARS-CoV-2 Monitoring

A Thermostable Cas12b fromBrevibacillusLeverages One-pot Detection of SARS-CoV-2 Variants of Concern

Contact Info

Product

Resources

About