Table 3.
Summary on microfluidic technology for SARS-CoV-2 antibodies detection.
| Method | Fluid manipulation technique | Material | Immobilized antigen/antibody/gene | Detected biomolecule | Detector | Sensitivity/% | Specificity/% | Sample size/donor/standard | Limit of detection (LOD) | Detection time | Advantage | Ref. |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Monolithic chips integrating a microfluidic chain reaction | Paper capillary pump | Transparent resin | N | Anti-N Abs | Naked eye or smartphone integrated with a folded origami box | – | – | – | 0.3 ng/mL | – | Frugal, versatile, bona fide lab-on-a-chip, sensitive, quantitative and reproducible. | 70 |
| Microfluidic DA-D4 point-of-care test (POCT) | Pipette pump | POEGMA | S1, N, RBD | Anti-S1, anti-N, anti-RBD Abs | Fluorescent detector | 100 (anti-S1 &anti-RBD) 96.3 (anti-N) | 100 | 46 plasma samples from 31 positive patients and 41 negative samples. | 0.12 ng/mL | 60 min | Easy to use, quantitative, high specificity and sensitivity, capable of measuring antibody kinetics and seroconversion directly from unprocessed blood or plasma, capable of detecting IP-10, low sample volume requirement, low cost. | 71 |
| Microfluidic nanoimmunoassay platform based on MITOMI | Pneumatic valves | PDMS | His-tagged S | Anti-S IgG | Nikon ECLIPSE Ti microscope equipped with a LED fluorescent excitation system and a Cy3 filter set | 98 | 100 | 289 positive and 134 negative samples | 1 nmol/L IgG | – | High sensitivity and specificity, high-throughput, negligible reagent consumption, ultra-flow volume blood sampling | 72 |
| Semi-automatic serological assay | Valve pump | PDMS | S, S1, RBD and N | Anti-S/S1/RBD/N IgG/IgN | Inverted fluorescence microscope | 95 | 91 | 100 serum samples from 66 positive patients | 1.6 ng/mL | 2.6 h | Low-cost, low sample/reagent consumption, multiple analyte detection, and high throughput. | 73 |
| Single molecule arrays | Commercial products | Commercial products | S ligated micron-sized beads | Anti-S Abs | Simoa HD-1 analyzer | – | – | 28 plasma samples from 10 positive patients | – | – | High throughput, rapid detection, and high specificity | 74 |
| An immunoassay based on dual-encoded beads and rolling circle amplification | Syringe pump | PDMS | S, N, RBD | Anti-S, anti-N, anti-RBD Abs | Fluorescent detector | 100 | 100 | 11 positive samples and 11 negative samples | – | – | High throughput, high sensitivity, tunable detection range | 75 |
| Decentralized, instrument-free microfluidic device | Capillary force | PDMS | S-RBD ligated magnetic beads, secondary Abs against human IgG ligated polystyrene beads | Anti-S RBD IgG | Direct visual inspection | 99 | 100 | 91 vaccinees | 13.3 ng/mL | 20 min | High specificity, low-cost, user-friendly interfaces, power-free operation, and quantification by visual inspection | 76 |
| Sandwich-based enzyme-linked immunosorbent assay on electrodes | DC pump | Grey resin | S1, N, RBD | Anti-S1, anti-N, anti-RBD Abs | Electrochemical biosensors | 100 | 100 | 3 saliva samples from actively infectious patients | 2.3 copies/μl | 50 min | Low-cost, self-contained, simple and sensitive readout for both viral RNA as well as host antibodies, and user-friendly | 77 |
‒, not applicable.