Photoluminescence Activation of Organic Dyes via Optically Trapped Quantum Dots
The spontaneous emission generated by two-photon excited quantum dots in an optical trap can in turn excite organic dyes. We demonstrate and exploit this phenomenon to acquire photoluminescence from selected regions of a stained biological sample with nanometer resolution.
Rodriguez-Rodriguez H, Acebron M, Iborra FJ, Arias-Gonzalez JR, Juarez BH.
ACS Nano 2019 Jun; 13: 7223.
Laser tweezers afford quantum dot (QD) manipulation for use as localized emitters. Here, we demonstrate fluorescence by radiative energy transfer from optically trapped colloidal QDs (donors) to fluorescent dyes (acceptors). To this end, we synthesized silica-coated QDs of different compositions and triggered their luminescence by simultaneous trapping and two-photon excitation in a microfluidic chamber filled with dyes. This strategy produces a near-field light source with great spatial maneuverability, which can be exploited to scan nanostructures. In this regard, we demonstrate induced photoluminescence of dye-labeled cells via optically trapped silica-coated colloidal QDs placed at their vicinity. Allocating nanoscale donors at controlled distances from a cell is an attractive concept in fluorescence microscopy because it dramatically reduces the number of excited dyes, which improves resolution by preventing interferences from the whole sample, while prolonging dye luminescence lifetime due to the lower power absorbed from the QDs.
PubMed: 31194513. Doi: 10.1021/acsnano.9b02835.
