Centre for Mass Spectrometry, Analytical & Structural Chemistry Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.
Academy of Scientific & Innovative Research (AcSIR), New Delhi, India.
J Mass Spectrom. 2020 Oct;55(10):e4605. doi: 10.1002/jms.4605.
The HPLC-DAD and GC/MS methods were successfully used for the identification and characterization of the impurities in an agrochemical insecticide, bifenthrin technical. Three impurities ranging from 0.175%-0.541% were detected by the HPLC-DAD method. The LC/MS technique with ESI or APCI source failed to detect the impurities detected by HPLC-DAD, due to lack of ionization in ESI or APCI. The three impurities were enriched by prep-HPLC, and then their structures were elucidated based on the GC/EIMS and CIMS data. The EI mass spectra of bifenthrin and its impurities displayed molecular ion and provided structure indicative fragment ions; the CIMS data further confirmed their molecular weight. The identity of the impurity 1 was further confirmed by the synthesis of the authentic sample followed by NMR and GC/MS data.
高效液相色谱-二极管阵列检测和气相色谱/质谱联用技术被成功用于鉴定和描述农用杀虫剂联苯菊酯原药中的杂质。高效液相色谱-二极管阵列检测法检测到 3 种杂质，其含量在 0.175%-0.541%之间。由于电喷雾或大气压化学电离源在电喷雾或大气压化学电离时缺乏离子化，因此，LC/MS 技术未能检测到高效液相色谱-二极管阵列检测法检测到的杂质。通过制备高效液相色谱对这 3 种杂质进行了富集，然后根据气相色谱/电子电离质谱和化学电离质谱数据对其结构进行了阐明。联苯菊酯及其杂质的 EI 质谱显示分子离子峰，并提供了结构特征碎片离子峰；化学电离质谱数据进一步证实了它们的分子量。通过合成纯品并结合 NMR 和 GC/MS 数据，进一步确认了杂质 1 的身份。
