Fluorescence detection in capillary zone electrophoresis using a charge-coupled device with time-delayed integration.
A fluorescence detection system for capillary zone electrophoresis is described in which a charged-coupled device (CCD) views a 2-cm section of an axially illuminated capillary column. The CCD is operated in two readout modes: a snapshot mode that acquires a series of images in wavelength and capillary position, and a time-delayed integration mode that allows long exposure times of the moving analyte zones. By use of the latter mode, the ability to differentiate a species based on both its fluorescence emission and migration rate is demonstrated for fluorescein and sulforhodamine 101. The detection limit for fluorescein isothiocyanate (FITC) is 1.2 X 10(-20) mol; detection limits for FITC-amino acids are in the (2-8) X 10(-20) mol range.
Sweedler
J V
JV
Department of Chemistry, Stanford University, California 94305.
Shear
J B
JB
Fishman
H A
HA
Zare
R N
RN
Scheller
R H
RH
D000596:Amino Acids / Q000032:analysis; D004553:Electric Conductivity; D004586:Electrophoresis / Q000379:methods*; D019793:Fluorescein; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins / Q000032:analysis; D013050:Spectrometry, Fluorescence; D013861:Thiocyanates
D000596:Amino Acids; D005452:Fluoresceins; D013861:Thiocyanates; D016650:Fluorescein-5-isothiocyanate; D019793:Fluorescein