Quick detection of heavy metal absorbable mercury in soil.

DTPA, EDTA and HC1 extractants were used to extract heavy metal absorbable mercury in the soil, by comparison, the highest extraction rate of the extractant DTPA was chosen. Then, the hollow carbon nanospheres/polyaniline composite was prepared. The composite was made into a DNA-modified hollow carbon nanospheres/polyaniline electrochemical sensor and the absorbable mercury in the soil was detected. The results showed that DTPA had the highest extraction rate of absorbable mercury in the soil from 20% to 31%. And the chemical sensor could detect the absorbable mercury content in soil accurately and sensitively. Compared with the results of atomic fluorescence spectrometry, the relative errors between the two actual samples were 2.32% and 2.71%, respectively. [ABSTRACT FROM AUTHOR]