Single molecule fluorescence measurements hold great promise for studying biological processes on a very small scale. These experiments are typically conducted using a scanning confocal fluorescence microscope.
The data rely on the focusing of excitation light to a specific point on a molecule, with the fluorescence output being collected using the same objective lens. The fluorescence output can be varied by changing the external electric field. But an out-of-focus excitation light, say scientists in Singapore, due to the not uncommon occurrence of damage to the type of thin film devices used in such experiments, can result in a decrease in the output fluorescence – which could potentially be misinterpreted as a significant effect.
The results indicate that researchers measuring fluorescence modulation using this electric field method should be aware that this type of artefact could interfere with their results.
Read more details about these interesting findings:
Other origins for the fluorescence modulation of single dye molecules in open-circuit and short-circuit devices
Edwin Yeow, Jefri Sanusi Teguh, Michael Kurniawan, Xiangyang Wu and Tze Chien Sum
DOI: 10.1039/C2CP43284F
