In‐column fiber‐optic laser‐induced fluorescence detection for CE

Abstract

A highly sensitive in-column fiber-optic LIF detector for CE has been constructed and evaluated. In this detection system, a 457-nm diode-pumped solid-state blue laser was used as the excitation light source and an optical fiber (40 mum od) was used to transmit the excitation light. One end of the optical fiber was inserted into the separation capillary and was in situ positioned at the detection window. The other end of the fiber was protruded from the capillary to capture the excitation light beam from the blue laser. Fluorescence emission was collected by a 40 x microscope objective, focused on a spatial filter, and passed through a yellow color filter before reaching the photomultiplier tube. The present CE-fluorescence detection is a simple and compact optical system. It reduces the laser scattering effect from the capillary and fiber as compared to the conventional LIF detection for CE. Its utility was successfully demonstrated by the separation and determination of D-penicillamine labeled with naphthalene-2,3-dicarboxaldehyde. The detection limit was 0.8 nM (S/N = 3). The present detection scheme has been proven to be attractive for sensitive fluorescence detection for CE.

Determination of riboflavin in urine and beverages by capillary electrophoresis with in-column optical fiber laser-induced fluorescence detection

“…To avoid these shortcomings, an optical fiber was inserted directly into the tail end of capillary and was settled right at the detection window in the new CE-LIF detection system. The excitation light was guided into the capillary directly and then could be utilized completely to excite analytes [25][26][27].…”

Enhanced Indirect Fluorescence Detection of p-Nitrophenol, 2,4-Dinitrophenol and Trinitrophenol by Micellar Electrokinetic Capillary Chromatography with In-column Optical-fiber LED-induced Fluorescence Detection

“…The in-column fiber-optics LED-IF for CE has been previously described. 25,27,28 To further improve the design, a fiber coupling device was used to match the precision translation stage (Fig. 1a) with the optical fiber.…”

HPLC with In-Capillary Optical Fiber Laser-Induced Fluorescence Detection of Picomolar Amounts of Amino Acids by Precolumn Fluorescence Derivatization with Fluorescein Isothiocyanate

“…Recently, our research group has successfully developed in-column optical fiber induced-fluorescence detection system for capillary electrophoresis (CE) [16][17][18][19][20][21][22][23][24][25]. For the in-column optical fiber induced-fluorescence detection system, our previous work demonstrated that an excitation light beam waveguided by an optical fiber to the detection point of the capillary shows relatively lower background light than that obtained from an excitation light beam impinged orthogonally on the capillary exterior wall.…”