Researchers have long succeeded in examining individual molecules to analyze their nanoscale structures and behaviors within biological frameworks. Nonetheless, differentiating between two adjacent dipole emitters—fluorescent molecules capable of emitting light in designated directions and intensities—has posed a significant challenge, particularly when these entities emit light simultaneously and are spatially coincident, or nearly situated at the same spatial point. This constraint has obstructed scientists’ endeavors to accurately measure the orientation and angular distance between dipoles, crucial for comprehending their rotational behaviors in densely populated cellular contexts.

Recent findings from Matthew Lew, an associate professor in electrical and systems engineering at the McKelvey School of Engineering at Washington University in St. Louis, along with first author Yiyang Chen, a graduate student in WashU’s imaging science doctoral program, demonstrate that current polarization imaging methods are inadequate to separate two coinciding dipole molecules from a single molecule.

To address this issue, Lew and Chen integrate two techniques, adjusting the polarization of the illuminating laser and assessing the polarization of the captured fluorescence, to differentiate between single and paired molecules. Their unified approach also enhances the accuracy in measuring the relative orientation of molecular pairs. The findings were published on March 7 in Physical Review Letters.

Discover more on the McKelvey Engineering website.

The article In molecular imaging, details matter was originally published on The Source.