Table 1. Photochemical and Photophysical Parameters Showing the Advantages of UCNPs in Imaging Compared to Dyes and QDs.
parameter | days | QDs | UCNPs |
---|---|---|---|
emission fwhm | 50 nm | 20–50 nm | <20 nm |
decay magnitude | 1 ns | 10 ns | 100 μs |
photobleaching | fast | slow | none |
photoblinking | yes | yes | no |
multiphoton excitation power (W/cm2) | 106–109 | 104–106 | 1–103 |