Table 1.
Advantages and disadvantages of common fluorescent probes.
| Probes | Examples | Advantages | Disadvantages | Ref. |
|---|---|---|---|---|
| UCNPs | NaYF4:Yb,Er; NaGdF4:Yb,Tm | Large anti-Stokes shift; Narrow emission spectra; Long fluorescence lifetime; Strong stability | Low quantum yield; Potential biotoxicity | 364 |
| Fluorescent proteins | GFP; RFP; BFP | High biocompatibility; Genetically encodable | Poor stability; Shallow tissue penetration; Moderate quantum yield | 365 |
| Organic dyes | Cy5; FITC; ICG | High quantum yield; Ease of functionalization and bioconjugation | Poor stability; Biotoxicity; Broad emission spectra | 366 |
| Quantum dots | CdSe@ZnS; CdTe; InP@ZnS | High quantum yield; Broad excitation spectra; Narrow tunable emission; Strong stability | Heavy metal toxicity; Photoblinking | 367 |
| Metal complexes | [Ru(bpy)3]2+; Ir(ppy)3 | Long fluorescence lifetime; Strong stability; Tunable redox activity | Heavy metal toxicity; Poor stability; Shallow tissue penetration | 368 |
| Carbon dots | Nitrogen-doped carbon dots; B-doped carbon dots | Low biotoxicity; Strong stability | Moderate quantum yield; Broad emission spectra; Limited functionalization and bioconjugation capacity | 369 |
GFP: green fluorescent protein; RFP: red fluorescent protein; BFP: blue fluorescent protein; Cy5: cyanine 5; FITC: fluorescein isothiocyanate; ICG: indocyanine green.