Optical | Colorimetric | Colorimetric changes help to make a visual observation for result interpretation | Sensitivity issues that lead to result inaccuracy | [ |
Fluorescence | Provides results with higher signal to noise ratio; higher sensitivity | Fluorescent labels are not visible at low concentration; requires external reader for specific analysis | [ |
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SERS | High sensitivity with very low detection limit; can be developed into ultiplex LFA for a wide range of detection | Expensive | [ |
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Chemiluminescence | High sensitivity when used together with metal nanoparticles; lower LOD; highly stable for immobilization | Requires addition of enzymatic substrate; low shelf-life | [ |
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Thermal | Thermal imaging | Improved LOD and high sensitivity; no photo bleaching or photo instability | The infrared image sensors are massive; expensive | [ |
Laser speckle imaging | Uses improved depth resolution reader that improves sensitivity | Expensive and not suitable at resource-limited settings | [ |
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PA imaging | PA imaging helps sample penetration deeper that improves the sensitivity of detection | Strips need to be dried before analysis since acoustic waves travelling through water-interface is a challenge | [ |
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Magnetic | MPQ | Low detection limit and highly sensitive | Not suitable for multiplex detection when using high affinity variants | [ |
Electrochemical | Amperometry, cyclic voltametric, impedimetric | The ratio of applied voltage can be adjusted to increase the sensitivity of the detection; nanoparticle integration to improve LOD | Requires expensive reagents and multistep procedure | [ |
Qualitative strip–based handheld POCT devices |
Immunochromatographic reaction Signaling depends on the simple visualization of olorimetric changes. Portable Test usually done at the site of patients’ care. E.g.: LFDs, ICSs, and multiplex LFDs |
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Quantitative strip or chip–based with unit use analyzers |
Used for quantitative analysis A reader is used to measure the reaction onto the strip. Allows to measure the INR levels of certain metabolites or proteins in our body. Test strips are for single use and disposed after the data collection. Common for blood sugar and thrombin analysis |
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Bench top POCT analyzers |
Requires sample containers, labelling and needed to be carried out in clinical settings. Can be set up at different POC locations. Miniaturized and increased computer processing. Used for spectrophotometric enzyme-substrate measurement, hemagglutination, immunoassay, and blood gas analysis. E.g.: agglutination assays, immunofiltration assays |
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Molecular biology–based/nucleic acid POCT devices |
Used for detection of pathogenic diseases. Rapidly quantifies nucleic acid from numerous infectious agents. Incorporated molecular biology techniques such as isothermal amplification reaction |