Method of analysis of a selected group of pyrethroids in soil samples using off-line flow-through extraction and on-column direct large-volume injection in reversed phase high performance liquid chromatography

Abstract

An analytical method using flow-through extraction of a soil sample filled in a short HPLC column with methanol or methanol-water mixtures and large-volume injection in RP-HPLC has been developed for the simultaneous determination of residues of three pyrethroids--kadethrin, cypermethrin, and permethrin--from soil samples. The developed RP-HPLC method enables separation of four diastereoisomers of cypermethrin into three peaks and resolution of two diastereoisomers of permethrin. The UV photometric detection limits of direct on-column large-volume injection of 1.00 mL of extract were 30 ng/mL of kadethrin, 37 ng/mL of total content of cypermethrin, and 65 ng/mL of trans-permethrin, which corresponds to a pyrethroid soil content of around 0.3 mg/kg. Effects of extractant flow rate and optimal extractant volume on the percentage recovery of pyrethroids from Slovak soil samples were studied. Recovery studies were performed at 0.5- 5.0 microg/g fortification level of kadethrin and 1.0-2.5 microg/g fortification level of cypermethrin and permethrin in a soil sample. Recoveries ranged from 83 to 90% for kadethrin, from 87 to 94% for total cypermethrin, and from 85 to 98% for trans-permethrin. This work comprises a basic study aimed at elaboration of an RP-HPLC method of direct analysis of pyrethroids in a soil matrix at low concentration levels achieved by a "solid sample injection" in HPLC--on-line interfacing of analyte extraction, extract clean-up, and analysis.

Method of fast trace microanalysis of the chiral pesticides epoxiconazole and novaluron in soil samples using off‐line flow‐through extraction and on‐column direct large volume injection in reversed‐phase high performance liquid chromatography

“…This work follows up on development of our ideas and results published in articles discussing the potential of combinations of chiral HPLC analysis of chiral pesticides [8], large volume injection (LVI) in RP HPLC [15], and flowthrough extraction of analytes from soil (micro)-samples [16]. The abbreviation LVI is used when a sample volume higher then 100 lL is injected onto an analytical HPLC column with conventional or smaller dimensions [15].…”

Trace analysis of environmental matrices by large-volume injection and liquid chromatography–mass spectrometry

“…With the advent of commercialized mass spectrometers fitted with multiple stage vacuum systems and with more efficient atmospheric pressure ionization (API) sources, higher LC flow rates, larger column diameters and larger injection volumes were made possible. An increasing number of publications have since appeared in the scientific literature that describe SC-LVI for use with mass spectrometry for the determination of pesticides in vegetables [20], water [21][22][23][24][25][26][27][28][29], and soil [30][31][32][33]; fluorochemicals in wastewater, groundwater and surface water [33][34][35][36][37]; neurotoxins in surface water, groundwater and drinking water [38,39]; pharmaceuticals (legal and/or illicit) in surface, ground, and waste water [25,33,[40][41][42][43][44]; corrosion inhibitors in surface, ground, and waste water [33,45]; chelating agents in surface, drinking, and waste water [46]; iodinated chemicals in waste water and treated water [47][48][49]; artificial sweeteners in ground, waste, and treated water [50]; biocides in surface and waste water [51]; bisphenol A in soil [33]; steroids in waste water [52]; and surfactants in seawater (unpublished) ( Table 2). The success and popularity of SC-LVI compared to ON-E and CC-LVI are most likely due to its sim...…”

“…Although most of the applications listed in Table 2 involve the direct injection of aqueous samples, several indicate that extracts of vegetables [20] or soil [30][31][32] are analyzed by SC-LVI ( Table 2). The final organic solvent-based extracts were diluted with water and the injected samples ranged in composition from 25% organic solvent (acetonitrile or methanol)/75% up to 70% organic solvent/30% water and then analyzed by SC-LVI.…”

“…There are a limited number of cases where SC-LVI is used for the analysis of pesticides extracted using organic solvents such as methanol from soil [31,32] and vegetables [20]. In each of these cases, the methanol extracts first are diluted to water to give sample compositions ranging from 25:75 to 70:30 (methanol:water).…”

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

“…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.…”