PROBING SINGLE SECRETORY VESICLES WITH CAPILLARY ELECTROPHORESIS

Secretory vesicles obtained from the atrial gland of the gastropod mol lusk Aplysia californica were chemically analyzed individually with a combination of optical trapping, capillary electrophoresis separation, and a laser-induced fluorescence detection. With the use of optical t rapping, a single Vesicle that had attoliters (10(-18) liters) of volu me was introduced into the tapered inlet of a separation capillary, On ce the vesicle was injected, it was lysed, and its components were flu orescently labeled with naphthalene-2,3-dicarboxaldehyde before separa tion, The resultant electropherograms indicated distinct variations in the contents of single vesicles.