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Novel integrated paired emitter-detector diode (PEDD) as a miniaturized photometric detector in HPLC

O'Toole, Martina and Lau, King-Tong and Schazmann, Benjamin and Shepherd, Roderick and Nesterenko, Pavel and Paull, Brett and Diamond, Dermot (2006) Novel integrated paired emitter-detector diode (PEDD) as a miniaturized photometric detector in HPLC. The Analyst, 131 (8). pp. 938-943. ISSN 1364-5528

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A novel low power, low cost, highly sensitive, miniaturized light emitting diode (LED) based flow detector has been used as optical detector for the detection of sample components in high performance liquid chromatography (HPLC). This colorimetric detector employs two LEDs, one operating in normal mode as a light source and the other is reverse biased to work as a light detector. Instead of measuring the photocurrent directly, a simple timer circuit is used to measure the time taken for the photocurrent generated by the emitter LED (λmax 500 nm) to discharge the detector LED (λmax 621 nm) from 5 V (logic 1) to 1.7 V (logic 0) to give digital output directly without using an A/D converter. Employing a post-column reagent method, a Nucleosil 100-7 (functionalised with iminodiacetic acid (IDA) groups) column was used to separate a mixture of transition metal complexes, manganese (II) and cobalt (II) in PAR. All optical measurements were taken by using both the in built HPLC variable wavelength detector and the proposed paired-emitter-detector-diode (PEDD) optical detector configured in-line for data comparison. The concentration range investigated using the PEDD was found to give a linear response to the Mn (II) and Co (II) PAR complexes. The effects of flow rate and emitter LED light source intensity were investigated. Under optimised conditions the PEDD detector offered a linear range of 0.9-100 µM and LOD of 0.09 µM for Mn-PAR complex. A linear range of 0.2-100 µM and LOD of 0.09 µM for Co-PAR complex was achieved.

Item Type:Article (Published)
Subjects:Physical Sciences > Detectors
Physical Sciences > Chemistry
DCU Faculties and Centres:DCU Faculties and Schools > Faculty of Science and Health > School of Chemical Sciences
Research Initiatives and Centres > Adaptive Information Cluster (AIC)
Research Initiatives and Centres > National Centre for Sensor Research (NCSR)
Publisher:Royal Society of Chemistry
Official URL:
Copyright Information:© The Royal Society of Chemistry 2006
Use License:This item is licensed under a Creative Commons Attribution-NonCommercial-Share Alike 3.0 License. View License
Funders:Science Foundation Ireland
ID Code:2976
Deposited On:16 Mar 2009 16:29 by martina o'toole. Last Modified 16 Aug 2013 09:39

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