Enantiomeric Separations of Pyriproxyfen and its Six Chiral Metabolites by High‐Performance Liquid Chromatography

Abstract

Pyriproxyfen is a chiral insecticide, and over 10 metabolites have been identified in the environment. In this work the separations of the enantiomers of pyriproxyfen and its six chiral metabolites were studied by high-performance liquid chromatography (HPLC). Both normal phase and reverse phase were applied using the chiral columns Chiralpak IA, Chiralpak IB, Chiralpak IC, Chiralcel OD, Chiralcel OD-RH, Chiralpak AY-H, Chiralpak AD-H, Chiracel OJ-H, (R,R)-Whelk-O 1, and Lux Cellulose-3. The effects of the chromatographic parameters such as mobile phase composition and temperature on the separations were investigated and the enantiomers were identified with an optical rotation detector. The enantiomers of these targets could obtain complete separations (resolution factor Rs > 1.5) on Chiralpak IA, Chiralpak IB, Chiralcel OD, Chiralpak AY-H, or Chiracel OJ-H under normal conditions. Chiralcel OJ-H showed the best chiral separation results with n-hexane as mobile phase and isopropanol (IPA) as modifier. The simultaneous enantiomeric separation of pyriproxyfen and four chiral metabolites was achieved on Chiralcel OJ-H under optimized condition: n-hexane/isopropanol = 80/20, 15°C, flow rate of 0.8 ml/min, and UV detection at 230 nm. The enantiomers of pyriproxyfen and the metabolites , , and obtained complete separations on Chiralpak IA, Chiralpak IC, and Lux Cellulose-3 under reverse phase using acetonitrile/water as the mobile phase. The retention factors (k) and selectivity factors (α) decreased with increasing temperature, and the separations were better under low temperature in most cases. The work is of significance for the investigation of the environmental behaviors of pyriproxyfen on an enantiomeric level.

State-of-the-art and recent developments of immobilized polysaccharide-based chiral stationary phases for enantioseparations by high-performance liquid chromatography (2013–2017)

“…Many papers are aimed to the determination of herbicides [103,104,108,110], insecticides [48,100,97,107,105], fungicides [102,109,106,101,99] or antiviral drugs [98] from many different chemical families, including aryloxyphenoxy propionic acids, pyridines, oxadiazines, phenylpyrazoles, acylalanines, pyrethroids, triazoles, α-aminophosphonates, sulfoxides, etc. have been determinated in environmental or food samples (soil, natural waters, fruits, vegetables, etc.).…”

“…have also been determined, especially in commercial products or biological samples (pharmaceutical formulations, human urine, human or animal blood, human plasma, animal serum, etc.). Another heterogeneous group of analytes, including connectors for building metal-organic frameworks [116,117,124], intermediates for the synthesis of pharmaceuticals [111], natural and synthetic compounds [39,113,121,120], biological compounds [82,112,58,71,78,86,[61][62][63]77,75], natural alkaloids [121], biomolecules [115,54], organometallic compounds [119] and chiral metabolites [103,108,100,97,102,59,63,52] has been enantioseparated with these immobilized polysaccharides CSPs (see Table 2-4). Fig.…”

In vivo estrogenicity of p-phenoxyphenol and p-pentyloxyphenol

“…The annual production of PhOP in United Kingdom was reported to be about 30 tons in 2007 19 . Studies have shown that PhOP can be released as a monomer or metabolite from PhOP-containing products 20 – 22 . Masao et al (2005) investigated the metabolism of the insect growth regulator pyriproxyfen in tomatoes plants and found that PhOP was detectable in tomato fruit as a metabolite.…”

Enantiomeric separation of prothioconazole and prothioconazole‐desthio on chiral stationary phases

“…Polysaccharide and brush-type CSPs are the two most widely used ones in many commercialized chiral columns. 10,11 Immobilized and coated polysaccharide CSPs have high enantiomeric selectivity and large load for many types of racemates. [12][13][14] Since the brush-type CSPs are formed by covalent bonding, the stability is excellent.…”