Table 2.
POC diagnostic strategies of COVID-19
| Type | Feature | Target | Sample | Method | LOD | Time (min) | Sensitivity/specificity | Ref |
|---|---|---|---|---|---|---|---|---|
| Nucleic acid testing |
Advantages: Sensitivity varies depending on the method, but is generally high Disadvantages: Some methods are time-consuming, costly and technically demanding, and not user-friendly |
M or N genes | Clinical swab | RT-LAMP, hCG-P, and PTSs | 0.5 copies μL−1 | 120 |
100%/100% (1 positive/16 negative) |
[19] |
| As1e, N, E genes | Nasopharyngeal swab | IoT, RT-eLAMP, and LoC | 20 copies μL−1 | 13 ~ 51 |
100%/100% (4 clinical samples) |
[20] | ||
| N gene | Saliva and nasopharyngeal samples | miSHERLOCK | 1.24 copies μL−1 | 60 |
96%/95% (27 positive/21 negative) |
[21] | ||
| E and N genes | Nasopharyngeal swab and sputum | NESBA | 0.5 copies μL−1 | 30 |
100%/100% (98 clinical samples) |
[27] | ||
| Antigen testing |
Advantages: rapid, low cost, simple operation, and high-throughput Disadvantages: false negatives based on viral load |
N protein | Viral samples | Antibody-coated GNPs and colorimetric readout | 150 ng mL−1 | 5 | - | [28] |
| N protein | Plasma samples | Self-powered microfluidic chip | 0.0031 ng mL−1 | 15 | - | [22] | ||
| S protein | Serum | LSG | 2.9 ng mL−1 | 60 |
100%/- (23 clinical samples) |
[29] | ||
| Antibody/serology testing |
Advantages: simple process and high accuracy Disadvantages: Detection time and sensitivity cannot be taken into account at the same time |
Total SARS-CoV-2 antibody | Serum | SQS-LFIA |
IgG: 0.10 ng mL−1 IgM: 0.04 ng mL−1 IgA: 0.06 ng mL−1 |
15 |
100%/100% (97 positive/300 negative) |
[23] |
| Anti-N antibody | Whole blood | ELISA | 5 ng mL−1 | ~ 20 | - | [24] | ||
| Antibody | Serum | MID | - | 21 |
97%/92% (170 clinical samples) |
[25] | ||
| IgM and IgG | Serum | MCIA |
IgM: 0.06 ng mL−1 IgG: 0.10 ng mL−1 |
30 | - | [26] |
RT-LAMP reverse transcription loop-mediated thermal amplification; hCG-P human chorionic gonadotropin (hCG)-conjugated toehold-mediated strand exchange (TMSE) probes; PTSs pregnancy test strips; IoT Internet of Things; RT-eLAMP real-time loop-mediated isothermal amplification; LoC lab-on-chip device; miSHERLOCK minimally instrumented SHERLOCK; NESBA nicking and extension chain reaction; LSG laser-scribed graphene; SQS-LFIA dSiO2/QD/SiO2 lateral flow immunoassay; ELISA enzyme-linked immunosorbent assay; MID magnetic immune detection; MCIA microflow cytometry-based agglutination immunoassay