Resolution of Deltamethrin, Permethrin, and Cypermethrin Enantiomers by High-Performance Liquid Chromatography with Diode-Laser Polarimetric Detection

Abstract

A normal-phase liquid chromatographic method is used to resolve the stereoisomers of the pyrethroid insecticides deltamethrin, cypermethrin, and permethrin by using two detectors: an ultraviolet (UV) spectrometer and a diode-laser polarimeter. In a mixture of enantiomers and diastereomers such as those resulting from the chemical structure of the pyrethroid insecticides with several asymmetric carbons, the UV spectrometer allows the detection of the diastereomers, whereas the diode-laser polarimeter permits the identification of the enantiomers. In this work, two enantiomers of deltamethrin, all four enantiomers of permethrin, and the four diastereomeric forms of cypermethrin are resolved without physical separation.

[The design of simple optical fiber laser polaristrobometer and DIY-spectropolarimeter for multivariate analysis of milk & diary products properties. Part I.]

“…Так как уже много лет известны методы поляриметрического детектирования при хроматографическом разделении (в частности -с использованием лазерных диодов [76]) 11 , а жидкостная хроматография широко используется при анализе молочной продукции [77], логично, пользуясь конструктивным подобием поляриметрической кюветы и хроматографической колонки, использовать поляриметрические методы на конструируемой установке в гибридизации с хроматографированием на ней.…”

HPLC Enantioseparation of the Alkaloid Canadine and Determination of Enantiomeric Purity With Chiral/Photometric and Achiral/Polarimetric Detection

“…Thus, we need to take into account that the injection peak is large. [33] Unfortunately, the polarimetric detector was not perfectly selective and responded to large refractive index changes. [34,35] This is most evident at the void volume when eluent and sample solvent were not identical.…”

HPLC‐method for determination of permethrin enantiomers using chiral β‐cyclodextrin‐based stationary phase

“…29 The separation and analysis of permethrin stereoisomers has been investigated. 7,[30][31][32][33][34][35][36] Different HPLC columns were used in RP and NP modes of analysis. The separations were not very successful, especially for transpermethrin enantiomers, and the reported analyses had very long run times.…”

“…By GC on a b-cyclodextrin-coated column they separated the cis-permethrin enantiomers with retention times of 84.0 and 85.4 min, but trans-permethrin was not separated. Novas et al 36 with NP chromatography obtained four permethrin enantiomer peaks using Pirkle type columns. Anadon et al 37 in their toxicokinetic studies with HPLC, and also Chalanyova et al 38 and Tulve et al 22 in their recent study separated and quantified only cis-from transpermethrin.…”