[Microchimica Acta]Real-time monitoring of the UV-induced formation of quantum dots on a milliliter,
Monitoring of formation of quantum dots (QDs) by UV irradiation in different volumes (mL, μL and nL) by fluorescence correlation spectroscopy and capillary electrophoresis with light emitting diode-induced fluorescence detection.
The authors report on a systematic study on the low-cost, low-temperature, and fast synthesis of water soluble quantum dots (QDs) stabilized by mercaptosuccinic acid by UV irradiation. The effects of UV irradiation (at 254 nm and 250 nm) and temperature on the precursors (Cd:Se, Cd:Te, Cd, Zn:S, Zn:Se and Zn) are described. Best results are achieved with a mixture of precursors containing cadmium, selenium and MSA where a 10-min irradiation with 254-nm light gives CdSe QDs with a quantum yield of 13.5%. The authors also describe the preparation and monitoring of the formation of QDs in sub-mg, sub-μg and sub-ng quantities, the smallest concentration being 258 pg in volume of 4 nL. The growth of the QDs can be monitored in real time by absorption, fluorescence and dynamic light scattering. The solutions of the particles also are characterized by fluorescence correlation spectroscopy and detected by LED-induced fluorescence. The preparation of such QDs by UV radiation is simple, easily controllable, and inexpensive. Conceivably, it can be integrated with lab-on-chip, micro total analysis systems or other instrumentation.
Lukas Nejdl, Jan Zitka, Filip Mravec, Vedran Milosavljevic, Ondrej Zitka, Pavel Kopel, Vojtech Adam, Marketa Vaculovicova
Nejdl, L., Zitka, J., Mravec, F. et al. Microchim Acta (2017). doi:10.1007/s00604-017-2149-8