Content Analysis of Zn, Pb, Cd and Cu Heavy Metal Elements in Grains

摘要

The differential pulse stripping voltammetry method was based on the articles in AOAC (Association of Official Analytical Chemists) and polarographic analyzer (EG&G) was adapted to normal laboratory conditions. The purchased Phaseolus angularis were pretreated and the heavy metalcontents of the Phaseolus Angularis (PA: China PA (CPA) and Korea PA (KPA)) were analyzed by differential pulse stripping (DPS) with a variational potential (–1.00～0.10 V). The values obtained in standard curve were recalculated in the statistic program of origin SW, and the resultsof heavy metal contents (μg/g) were compared to China PA (CPA) and Korea PA (KPA). The contents of CPA were 54.59 ± 1.58 ppm for Pb2+ (–0.3～–0.5 V), 2.31 ± 0.15 ppm for Cd2+ (–0.5～– 0.7 V), and 1.53 ± 0.08ppm for Cu2+ (0.0～–0.1 V). While on the KPA was 7.31 ± 0.09 ppm for Pb2+, 0.23 ± 0.06 ppm and 0.82 ± 0.08 ppm. The linearity for the calibration was from 10 ppb to 100 ppm for Pb2+.