Ascorbic acid as a reducing agent for phosphorus analysis by colorimetry

作者：Santos Lenio da Silva; da Silva Leandro Souza^*; Griebeler Gustavo

来源：Ciencia Rural, 2014, 44(6): 1015-1018.

• soil test
• reducing agents
• Mehlich-1
• Mehlich-3

In soil laboratory testing, the acid 1-amino-2-naphthol-4-sulfonic (ANS) is used as reducing agent to determine P by UV/Visible spectrometry. However, there are risks to laboratory technician healthy and an alternative is the use of ascorbic acid (AA). But, changes in the analytical protocol may induce variations in results, been necessary to standardize and calibrate. The objective of this study was to evaluate the ANS and AA in extracts of Mehlich-1 and 3 in ranges 15, 30, 45, 60 and 120min of reaction. There was no difference in P concentration determined by both reducers when compared within each extractor. Ascorbic acid can substitute the ANS solution for P determination and the suggested reaction interval for colorimetric quantification is between 30 and 60min for both substances.

• 出版日期2014-6