Provided herein are methods for measuring molecular flux rates of molecules of interest in a tissue sample in spatially-organized manner and generating output (e.g., an image, a heat map, a contour map, a table or a database) representing the molecular flux rates of each spatially-defined location of the sample. Provided herein are also the output, as well as systems and computer-readable medium with computer-executable instructions for determining molecular flux rates of molecules of interest in the sample.
STATEMENT REGARDING GOVERNMENTAL SUPPORT
 This invention was made with Government support under Contract No. DE-AC03-05CH11231 awarded by the Department of Energy. The Government has certain rights in the invention.