The DAPI-based fluorometric quantification of polyphosphate in microalgae has been widely used in field samples since the method was published by Martin P. et. al., where fluorescence of DAPI-stained samples is analyzed in quartz cuvettes by spectrofluorometer. In order to minimize the photobleaching of DAPI and reduce the consumption of reagent, time and labor, we have now scaled this method to 96-well black microtiter plate. Regarding to the matrix effects in microplate, the calculation has been modified accordingly. Our method permits processing large numbers of samples by using only 250 uL of extracted sample and 30 uL of DAPI (100 uM). A lid with black film can protect all DAPI-stained samples from photobleaching. .justify:after { content: ""; display:inline-block; width: 100%; } .justify:after { content: ""; display:inline-block; width: 100%; }