A multiresidue method using gas chromatography (GC) and gas chromatography/ mass spectrometry (GC/MS) was developed for the determination of several organochlorine pesticides in three crude drugs: Astragali Radix Zizyphi Sativae Fructus and Zingiberis Rhizoma. The pesticides including α-BHC, β-BHC, γ-BHC, δ-BHC, 2,4'-DDE, 4,4'-DDE, 2,4'-DDT and 4,4'-DDT were determined using a modified extraction and refining procedure, separated by a capillary column (DB-1, 0.25 μm, 0.25 mm × 30 M), observed with an electron capture detector (ECD), and confirmed by GC/MS if necessary. The precision and accuracy were satisfactory. Calibration graphs of eight pesticides were constructed in the range of 0.25-2.0 μg/ml and their correlation coefficients (r) were in the range of 0.995-0.998. Recovery studies were performed at the 1.0 ppm spike level of each pesticide in these three crude drugs. Recovery rates were 66.4-98.0% for Astragali Radix, 36.7-86.9% for Zizyphi Sativae Fructus, and 31.1-109.7% for Zingiberis Rhizoma. Coefficients of variation were between 2.3 and 4.9%. The estimated limits of detection of the pesticides were all below the 0.06 ppm level. Coefficients of variation ranged between 6.3 and 10.2%. This analysis method could be also applied to concentrated Chinese medicines.
Lai, W.-L.; Shaw, J.-R.; and Sheu, C.
"Determination of Organochlorine Pesticides in Crude Drugs,"
Journal of Food and Drug Analysis: Vol. 7
, Article 5.
Available at: https://doi.org/10.38212/2224-6614.2875