Simple luminescence detectors using a light-emitting diode or a Xe lamp, optical fiber and charge-coupled device, or photomultiplier for determining proteins in capillary electrophoresis: a critical comparison.
The performance of two homemade fluorescence-induced capillary electrophoresis detectors, one based on light-emitting diode (LED) as the excitation source and a charge-coupled device (CCD) photodetector and the other based on a commercial luminescence spectrometer (Xe lamp) as the excitation source and a photomultiplier tube as a detector, were compared for the determination of fluorescent proteins R-phycoerythrin and B-phycoerythrin. Both devices use commercially available, reasonably priced optical components that can be used by nonexperts. After fine optimization of several optical and separation parameters in both devices, a zone capillary electrophoresis methodology was achieved with 50mM borate buffer (pH 8.4) and 10mM phytic acid for the determination of two phycobiliproteins. Detection limits of 0.50 and 0.64microg/ml for R-phycoerythrin and B-phycoerythrin, respectively, were achieved by using the LED-induced fluorescence capillary electrophoresis (LED-IF-CE) system, and corresponding detection limits of 2.73 and 2.16microg/ml were achieved by using the Xe lamp-IF-CE system. Analytical performance and other parameters, such as cost and potential to miniaturization, are compared for both devices.
Casado-Terrones
Silvia
S
Department of Analytical Chemistry, Faculty of Sciences, University of Granada, E-18071 Granada, Spain.
Fernández-Sánchez
Jorge F
JF
Segura-Carretero
Antonio
A
Fernández-Gutiérrez
Alberto
A
D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design / Q000295:instrumentation*; D005336:Fiber Optic Technology; D049449:Luminescence; D055100:Optical Fibers; D052979:Phycobiliproteins / Q000032:analysis / Q000737:chemistry; D010799:Phycoerythrin / Q000032:analysis* / Q000737:chemistry; D011506:Proteins / Q000032:analysis*; D012680:Sensitivity and Specificity; D014978:Xenon
D052979:Phycobiliproteins; D011506:Proteins; D010799:Phycoerythrin; D014978:Xenon