Publication Abstract
- Title
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Project ME4117 – Development and Improvement of Analytical Methods for Marine Monitoring. 4.2 – Determination of Chlorophyll in seawater by HPLC
- Publication Abstract
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Chlorophyll determination has been routinely conducted at Cefas by filtration extraction of chlorophyll from seawater and the filtrate dissolved in acetone prior to fluorescence detection using a cell fluorescence spectrometer. The method is not able to discriminate between the different analogues of chlorophyll so an HPLC technique has been employed initially to be selective for Chlorophyll a. Following a short literature survey of publications citing chlorophyll analysis by HPLC, a method by Buchaca et al [5] was adapted for the study and tested at Cefas. The method offered the simplest HPLC set-up with a faster sample through-put than the other chromatographic techniques published.
Sample preparation was unchanged from the previous Cefas technique where 250 mL of seawater is filtered through a GFS filter. The filter is then extracted with 90% acetone. The HPLC system was a reversed phase binary gradient system with UV/Visible spectrophotometric detection. A series of dilutions of chlorophyll a standard determined a signal to noise of 3:1 at 10 µg/L of a standard solution in 90% acetone: water (equating to 0.3 µg/L in seawater). Linearity was good (R2 > 0.99) over a range 50 – 1000 µg/L in solvent (equating to 1.6 to 32 µg/L in seawater).A batch of seawater extracts (n=23) were analysed using the conventional cell fluorescence and HPLC techniques. Under the HPLC conditions applied, of all samples analysed, no other peaks were detected other than chlorophyll a and allomers. A standard of chlorophyll b was later procured and analysed under the same conditions. The two chlorophyll species could easily be resolved chromatographically and gave similar response factors.Of the 23 samples analysed, seawater chlorophyll levels ranged between 0.5 and 5.3 for 22 samples with one elevated level at 11.4 µg/L. The same samples analysed independently using the original cell fluorescence technique gave similar and comparable results.
- Publication Internet Address of the Data
- Publication Authors
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M. Philo
- Publication Date
- September 2011
- Publication Reference
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Cefas Technical Report
- Publication DOI: https://doi.org/
