Just like watching boats in the night, seeing movement at the nanoscale is easier when the object you are watching has a beacon.Dynamic three-dimensional tracking with high precision is possible with nanoscale light emitting particles known as quantum dots at better resolution than 10 nanometers in the vertical direction. This opens up the possibility for understanding three dimensional movement in nanoscale structures and biological systems. The quantum dots are followed using the technique known as scanning-angle total internal reflection fluorescence microscopy (SA-TIRFM). Quantum dots hold advantages over other fluorescent probes because they can be tuned to emit various colors of light. Many, however, will spontaneously “blink” meaning the emitted light is suddenly turns off (or on) thus interrupting measurements. Researchers have developed "non-blinking" quantum dots that make them useful for high precision tracking in dynamic environments. This methodology was used to show the potential of motor proteins as components in nanomachines to transport cargo.
High-Precision Tracking with Non-blinking Quantum Dots Resolves Nanoscale Vertical Displacement