A Comparative Study on the Analysis Methods for Chlorophyll-a

This paper investigated three chlorophyll-a analysis methods in water sample. The UV-VIS spectrophotometry method followed SL88-2012 standard procedure, the results showed the detection limit of chlorophyll-a was 0.22 μg/L, with the lower detection limit of 1.0 μg/L. The detection range of the vivo chlorophyll-a fluorescence method was 0.1-300μg/L, the ratios of different algae matched that prepared in water samples. The detection limits and quantification limits for HPLC by using UVD and FLD were respectively 0.013 and 0.004 μg/L, 0.040 and 0.013μg/L. FLD was more sensitive than UVD for chlorophyll-a analysis, and the recovery of standard addition was in the range of 90.2% to 103.9% with UVD and FLD. Given the different pretreatment procedures of the sample, equipment conditions, correction and precision, vivo chlorophyll-a fluorescence method was the best on-site monitoring and the emergency monitoring method. Spectrophotometer was suitable for routine laboratory determination of chlorophyll-a, especially for bulk water samples. HPLC method had high precision and sensitivity, so this method applied to the determination of exact requirements, microanalysis and pigment separation.