Combined photometric detector utilizing light emitting diodes, 50 nL silica capillary cell, and CCD spectrometer

0509158 - ÚIACH 2020 PL eng A - Abstract
Šesták, Jozef - Kahle, Vladislav
Combined photometric detector utilizing light emitting diodes, 50 nL silica capillary cell, and CCD spectrometer.
CECE 2019. Gdańsk: University of Gdańsk, 2019. s. 45-45.
[CECE 2019. International Interdisciplinary Meeting on Bioanalysis /16./. 24.09.2019-26.09.2019, Gdańsk]
R&D Projects: GA MV VI20172020069
Institutional support: RVO:68081715
Keywords : capillary LC * absorbance-fluorescence detector * capillary detection cell * CCD spectrometer * light-emitting diodes
OECD category: Analytical chemistry

Many LC methods utilize absorbance and fluorescence detectors connected in series as a versatile detection strategy for quantitation of target fluorophores and non-fluorescent molecules within single run. However, the use of two bulky detectors is not a useful strategy for capillary LC (column I. D. typically less than 300 μm), where detector should be equipped with a miniaturised detection cell and positioned as close as possible to the column outlet to keep an extra column band broadening within acceptable limits. An effort to integrate absorbance and fluorescence monitoring into a single detection cell and detector device is thus a logical step. Here we present a compact photometric detector design which uses light emitting diodes (LEDs) as the light source, customized 50 nL L-shaped silica capillary detection cell [1], and CCD spectrometer as the light detector. 265 nm LED is used as the light source for measurement of absorption while 365 nm and 470 nm LEDs are used for fluorophore excitation. Presented results demonstrate 1 mm effective optical path of the detection cell and extremely low level of stray light such that upper limit of dynamic range is more than 2.5 AU. Response of the detector is linear over three orders of magnitude of concentration. Detection capabilities are demonstrated by LODs of uracil, anthracene and fluorescein of 2×10-6 M, 1×10-8 M, and 1×10-9 respectively.
Permanent Link: http://hdl.handle.net/11104/0299925