LED illumination for video-enhanced DIC imaging of single microtubules.

In many applications high-resolution video-enhanced differential interference contrast microscopy is used to visualize and track the ends of single microtubules. We show that single ultrabright light emitting diodes from Luxeon can be used to replace conventional light sources for these kinds of applications without loss of function. We measured the signal-to-noise ratio of microtubules imaged with three different light emitting diode colours (blue, red, green). The blue light emitting diode performed best, and the signal-to-noise ratios were high enough to automatically track the ends of dynamic microtubules. Light emitting diodes as light sources for video-enhanced differential interference contrast microscopy are high performing, low-cost and easy to align alternatives to existing illumination solutions.