Table 3.
Transducer | Detection Technique | Analyte | Sample | Limit of Detection (nM *) | Ref. |
---|---|---|---|---|---|
Homo- and co-polymers | |||||
Silicon platform/poly(DMA-co-NAS-co-MAPS)/Antibodies/Analyte/Secondary Antibodies/Cyanine 3 | Fluorescent detection | Aβ42 | aCSF | 0.016 * | [98] |
SPGE/POPA co-polymer/PrPC (95–110) | EIS | Aβ oligomers | DMSO/F12 medium and Chinese hamster ovary cell line | 5 × 10−4 | [99] |
Interdigitated microelectrode/SiO2/APMES/Polyvinyl pyrrolidone-aldehyde solution/Sodium borohydride/Glutaraldehyde/Antibodies | Impedance | Aβ42 | Buffer and mouse plasma | 2.2 × 10−5 | [100] |
Ion concentration polarization-based preconcentration-Interdigitated microelectrode/SiO2/APMES/Polyvinyl pyrrolidone-aldehyde solution/Sodium borohydride/Glutaraldehyde/Antibodies | Impedance | Aβ42 | Buffer | 8.15 × 10−6 | [101] |
Glass slides/Au film/SAM of carboxyl- and hydroxyl-terminated PEG/Antibodies/Analyte/Antibody | SPR | Aβ40/Aβ42 | Buffer and CSF | 0.02 | [102] |
Conducting Polymers | |||||
AuE/Poly (pyrrole-2-carboxylic acid)/PrPC | EIS | Aβ oligomers | Buffer and Brain samples | 10−7 | [103] |
* Value expressed in μg mL−1/ng mL−1/pg mL−1 and converted to nM. aCSF, Artificial cerebrospinal fluid; APMES, 3-(ethoxydimethylsilyl) propylamine; AuE, Gold electrode; CSF, Cereborspinal fluid; DMSO, Dimethyl sulfoxide; EIS, Electrochemical impedance spectroscopy; PEG, Polyethylene glycol; poly(DMA-co-NAS-co-MAPS), Ter-copolymer made with an optimized composition of dimethylacrylamide (DMA), 3-(trimethoxysilyl)propyl methacrylate (MAPS) and N-Acryloyloxy succinimide ester (NAS); POPA, Co-polymer of polytyr-amine/3-(4-hydroxyphenyl) propionic acid; SAM, Self-assembled monolayer; SPGE, Screen-printed gold electrode; SPR, Surface plasmon resonance.