Water-soluble quantum dots used to image capillaries

Extremely bright, water-soluble quantum dots can be used to image capillaries within the dermis with cellular resolution. In this image, collagen is imaged by second harmonic generation (blue) and the quantum dots are imaged by two photon fluorescence excitation (yellow). Red blood cells exclude the quantum dots, forming shadows within the capillaries, which can be monitored over time (yellow trace). Image Courtesy of Dr. Watt W.Webb of Cornell University, Grant No. EB001976

Image courtesy of Dr. Watt W.Webb, Cornell University. Grant EB001976