High-sensitivity chromatographic detector incorporating three-dimensional charge coupled device fluorimetry.
This article describes a detector for liquid chromatography that provides three-dimensional, excitation-emission-intensity data of fluorescent compounds. The instrument achieves multi-wavelength excitation by employing a polychromator that disperses radiation along the vertical portion of a quartz capillary flow cell. The ensuing sample fluorescence is collected in the horizontal plane and dispersed using an emission polychromator to form a focused two-dimensional excitation-emission image at a charge coupled device (CCD) pixel array. Each vertical pixel equates to a narrowly defined excitation wavelength band, whilst horizontal pixels equate to corresponding emission wavelengths, with the intensity of light encroaching onto the CCD pixel elements providing the third-dimensional variable in the measurement. It is shown that the extreme sensitivity of CCD detection coupled to the dual polychromator arrangement makes possible the collection of fluorescence excitation-emission-intensity data of polycyclic aromatic hydrocarbons in a flow stream in less than 0.05 s with nanogram per millilitre limits of detection.
Setford
S J
SJ
Cranfield Centre for Analytical Science, IBST, Cranfield University, Bedford, UK.
Saini
S
S
D000873:Anthracenes / Q000032:analysis; D002138:Calibration; D002853:Chromatography, Liquid / Q000295:instrumentation*; D005449:Fluorenes / Q000032:analysis; D010616:Phenanthrenes / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*
D000873:Anthracenes; D005449:Fluorenes; D010616:Phenanthrenes; C027704:benzo(j)fluoranthene; C031181:phenanthrene; C034020:anthracene