improvement of the wet-oxidation procedure for simultaneous determination of particulate organic nitrogen and phosphorus collected on filters

Abstract

A new digestion technique is presented for simultaneous analysis of particulate organic nitrogen (PON) and particulate organic phosphorus (POP) collected on filters. This method is based on a standard persulfate digestion procedure at 120C and adapted from a former method for the simultaneous determinat~on of total nitrogen and total phosphorus in natural waters. Comparisons 1~1th usual methods using separate determinations for PON and POP indicate a high efficiency of the procedure for cell cultures or natural seawater samples. N ~t r a t e and phosphate formed by oxidation can be analysed s~multaneously on an automated system. The procedure is highly suitable for routlne analysis and especially appropriate for shipboard use.