Table 3. Summarized Examples of the Use of Radiative and Nonradiative Energy-Transfer Sensorsa.
| QDs | λmax emission (nm) | capping | modifications and functionalization | modification method | size (nm) | target | cell line | LOD value (mol L-1) | ref |
|---|---|---|---|---|---|---|---|---|---|
| CdTe/CdS core–shell | 580 | MPA | thiolated DNA | ligand exchange | DNA | 10 × 10–15 | (13) | ||
| miRNA-21 | 100 × 10–15 | ||||||||
| QD605sAv | 605 | short 8 nucleotide DNA sequences | biotin-labeled oligonucleotides | hsa-miR-20a-5p; hsa-miR-20b-5p; hsa-miR-21–5p | 1 × 10–9 | (15) | |||
| QD655-sAv | 655 | ||||||||
| QD705-sA | 705 | ||||||||
| CdSe/ZnS | 627 | ODA | GSH; 50-amino-functionalized nucleic acid | ligand exchange | miRNA-141 | (63) | |||
| CdTe | 630 | GSH | phosphorothioate-DNA | 3.8 | miRNA-21 | HeLa; MCF-7; MDA-MB-231 | 4.56 × 10–9 | (97) | |
| ZnS | MPA-capped and Mn-doped | PDDA | 5 | miRNA-21 | 0.16 × 10–9 | (133) | |||
| CdSe@ZnS | 530 | MPA | thiol-modified DNA | 8 | miRNA-21 | HeLa | 1.5 × 10–12 | (64) | |
| CdTe | 625 | 5 | miRNA-141 | 22Rv1 | |||||
| CdTe | 535 | MPA | DNA | carbodiimide coupling (EDC/NHS) | 2.23 | miRNA-122 | 9.4 × 10–12 | (50) | |
| CdSxSe1–x/ZnS (core/shell) | 525 | oleic acid | His6-tag DNA | ligand exchange | miRNA-148 | MCF-7; MDA-MB-231 | 42 × 10–15 | (65) | |
| 570 | miRNA-21 | ||||||||
| CdSe/ZnS core/shell | 525 | streptavidin | ∼15 | miRNA- 21 | MCF-7; HEK-293; HeLa | 7.2 × 10–16 | (12) | ||
| miRNA-221 | 1.6 × 10–17 | ||||||||
| CdTe | 631 | DNA | 3.7 | miRNA-21 | HEK-293; HeLa | 10.4 × 10–12 | (134) | ||
| CdTe | 550 | 5 | miRNA-155 | MCF-7; HEK-293 | 12.0 × 10–12 | (135) | |||
| CdTe | 530 | TGA | 5 | miRNA-155 | SK-BR-3; MCF-7; HEK 293 | 0.42 × 10–12 | (136) | ||
| CdTe | 618 | DNA 1–AuNPs and DNA 2–AuNPs | AuNPs, 20.8; QDs, 3.4 | miRNA-21; miRNA-122 | (137) | ||||
| CdTe | 525 | mercaptoacetic acid (MAA) | DNA | 2 | miRNA-155 | MCF-7; HEK-293 | 14.0 × 10–12 | (138) | |
| 599 | |||||||||
| CdSe | 617 | multishell: CdS, CdZnS, and ZnS; silica encapsulation | DIBO; anti-AGO2 antibody | site-click coupling | 20 | (75) | |||
| carbodiimide coupling (EDC/NHS) | |||||||||
| carboxyl-modified | 525 | DNA | carbodiimide coupling (EDC/NHS) | miRNA-21 | 36.0 × 10–12 | (139) | |||
| 565 | miRNA-20a | 35.1 × 10–12 | |||||||
| 605 | miRNA-155 | 36.5 × 10–12 | |||||||
| 650 | miRNA-221 | 38.3 × 10–12 | |||||||
| QD605sAv | 605 | streptavidin | biotin-labeled oligonucleotides | miRNA-155 | HL7702; MCF-7; HeLa | 6.32 × 10–17 | (140) | ||
| CdTe | 542 | MPA | DNA | streptavidin–biotin | 2.3 | miRNA-33 | 0.09 × 10–9 | (141) | |
| 630 | 4.1 | miRNA-125b | 0.02 × 10–9 |
a
TGA, thioglycolic acid; MPA, 3-mercaptopropionic acid; DNA, deoxyribonucleic acid; EDC, 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride; NHS, N-hydroxysuccinimide; miRNA, micro ribonucleic acid; GSH, l-glutathione reduced; His6-tag, hexahistidine; ODA, octadecylamine; AuNPs, gold nanoparticles. FePc, iron phthalocyanine; DIBO, dibenzocyclooctyne; PDDA, poly(diallyldimethylammonium chloride); QD605sAv, streptavidin-coated 605 nm-emitting quantum dots.