Table 1.
A comparative study between the proposed carbon quantum dots/gold (CQDs/Au) nanocomposite immunoassay technique and the other previously published approaches.
| Technique | Principle | Linear Concentration Range U mL−1 | Detection Limit U mL−1 | Reference |
|---|---|---|---|---|
| Electrochemical immunoassay | Immobilization of CA 19-9 antigen with titania sol–gel on a graphite electrode | 3–20 | 2.68 | [10] |
| Chemiluminescent immunosensor assay | Immobilization of CA 19-9 antigen on the cross-linked membrane | 2.0–25 | 1.0 | [11] |
| Chemiluminescent enzyme immunoassay | Using a derivative of 1,2-dioxetane phosphate to measure alkaline phosphatase as a labeling enzyme for the detection of CA 19-9 | 6.0–520 | 0.26 | [9] |
| ZnO quantum dots immunoassay | Employing ZnO quantum dots as an electrochemical and luminescent immunoassay | 0.1–180 1.0–180 |
0.04 0.25 |
[12] |
| Amperometric electrochemical immunoassay | Immobilization of CA 19-9 antibody on three-dimensional ordered macroporous magnetic sensors | 0.05–15.65 | 0.01 | [13] |
| Proposed CQDs/Au nanocomposite immunoassay method | Using CQDs/Au nanocomposite in the detection of CA 19-9 by a solid- phase immunoassay | 0.01–350 | 0.007 | Present study |