δ bhc

All pesticides standards including α-BHC(100 mg L⁻¹), β-BHC (100 mg L⁻¹), γ-BHC (100 mg L⁻¹), δ-BHC (100 mg L⁻¹), p,p′-DDE (100 mg L⁻¹), o,p′-DDT (100 mg L⁻¹), p,p′-DDT (100 mg L⁻¹), p,p′-DDD (100 mg L⁻¹), azoxystrobin (99.0%), carbendazim (99.0%), chlorothalonil (98.9%), chlorpyrifos (99.5%), cypermethrin (98.2%), chlorantraniliprole (98.2%), dichlorvos (99.7%), difenoconazole (99.2%), fenpropathrin (98.9%), isocarbophos (98.9%), procymidone (99.5%), prochloraz (99.2%), pyraclostrobin (98.1%), thiophanate-methyl (99.3%), tebuconazole (99.5%) and λ-cyhalothrin (93.5%) were purchased from Dr Ehrenstorfer GmbH (Augsburg, Germany). Acetonitrile (HPLC grade) were provided by Bangyi Chemical Co., Ltd. (Hangzhou, China). Anhydrous magnesium sulphate, anhydrous sodium sulphate and n-hexane were of analytical grade. Primary secondary amine (PSA) was provided by Agela Technologies.
Each single element stock solution (1000 mg L⁻¹) of Cu, Zn, Cr, Ni, Pb, As, Cd, and Hg were purchased from National Standard Material Research Centre (Beijing, China). Guaranteed reagent nitric acid (HNO₃) was provided by Fanhong Trading Co., Ltd. (Guangzhou, China).