Toward a Generic Extraction Method for Simultaneous Determination of Pesticides, Mycotoxins, Plant Toxins, and Veterinary Drugs in Feed and Food Matrixes

Abstract

A fast and straightforward generic procedure for the simultaneous extraction of various classes of pesticides, mycotoxins, plant toxins, and veterinary drugs in various matrixes has been developed, for subsequent analysis by liquid chromatography with mass spectrometric detection. As a first step, four existing multianalyte procedures and three newly proposed methods were compared for a test set of 172 pesticides, mycotoxins, and plant toxins spiked to a feed matrix. The new procedures, which basically involved extraction/dilution of the sample with water and an acidified organic solvent (methanol, acetonitrile, or acetone), were most promising. The three new generic extraction methods were further tested for applicability to other matrixes (maize, honey, milk, egg, meat). Overall, the best recoveries were obtained for acetone, followed by acetonitrile. With respect to matrix effects, acetonitrile was the most favorable solvent and methanol was the worst. The occurrence of matrix effects decreased for the matrixes in the order of feed > maize > meat > milk > egg > honey. The extraction method selected as the default procedure (water/acetonitrile/1% formic acid) was also evaluated for applicability to multiple classes of veterinary drugs in all six matrixes, with satisfactory results. Finally, the generic extraction procedure was validated for 136 pesticides, 36 natural toxins, and 86 veterinary drugs in compound feed and honey at three levels (0.01, 0.02, and 0.05 mg/kg) using ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for analysis of the extracts. For over 80% of the analytes, recoveries were between 70 and 120% and precision (expressed as relative standard deviation) was mostly in the range of 5-10% (except for feed at 0.01 mg/kg; adequate recoveries for 62% of the analytes). The limits of detection were from <0.01 to 0.05 mg/kg for most analytes, which is usually sufficient to verify compliance of products with legal tolerances. The results clearly demonstrate the feasibility of the generic approach proposed. Application of the method in routine monitoring programs would imply a drastic reduction of both effort and time.

Development and validation of a streamlined method designed to detect residues of 62 veterinary drugs in bovine kidney using ultra‐high performance liquid chromatography – tandem mass spectrometry

“…[20][21][22][23][24] The MMM of Kaufmann et al [25] was also performed, but it was deemed to be too laborious and time-consuming for our purposes. Each method had advantages in some respect over the others.…”

“…In each method, the last step was to filter a 0.5-ml portion of the final extract using a Whatman (Florham Park, NJ, USA) Mini-Uniprep PVDF 0.2 mm filter vial followed by analysis using UHPLC-MS/MS. MMM 1 was from Mol et al [20] with minor modifications. The samples in 50-ml PP tubes were extracted with 15 ml of MeCN/water (75/25 v/v) with 1% formic acid by vortex shaking for 30 min.…”

“…Table 3 shows that our concerns were misplaced, at least for the majority of Table 2a. Summary of qualitative results in the comparison of 5 MMMs for the 62 veterinary drugs in bovine kidney: drugs that gave >2 nonidentifications (false negatives) among 22 sample extracts Mol et al [20] Martos et al [21] Mastovska & Lightfield [22] Stubbings et al [23] Chiaochan et al [24] Erythromycin [20] 23 Amoxicillin; Ampicillin; Carbadox; Cefazolin; Chlortetracycline; Cloxacillin; Dicloxacillin; Erythromycin; Florfenicol Amine; Oxacillin; Ractopamine; Salbutamol; Sulfanilamide; Sulfapyridine; Tetracyline; Tylosin Martos et al [21] 20 Ampicillin; Carbadox; Chlortetracycline; Cloxacillin; Difloxacin; Enrofloxacin; Erythromycin; Florfenicol Amine; Oxacillin; Oxyphenylbutazone; Oxytetracycline; Sulfanilamide; Tetracyline Mastovska & Lightfield [22] 25 Amoxicillin; Ampicillin; Cefazolin; Chlortetracycline; Ciprofloxacin; Clindamycin; Cloxacillin; Dicloxacillin; Gamithromycin; Oxacillin; Oxyphenylbutazone; Oxytetracycline; Pirlimycin; Sulfanilamide; Tetracyline; Tilmicosin; Tulathromycin; Tylosin Stubbings et al [23] 21 Amoxicillin; Ampicillin; Beta/Dexamethasone; Carbadox; Cefazolin; Chloramphenicol; Chlortetracycline; Erythromycin; Oxyphenylbutazone; Oxytetracycline; Pirlimycin; Tetracyline; Tylosin Chiaochan et al [24] 26 Amoxicillin; Cefazolin; Clindamycin; Cloxacillin; Dicloxacillin; Erythromycin; Florfenicol Amine; Flunixin; Gamithromycin; Oxacillin; Oxyphenylbutazone; Salbutamol; Sulfabromomethazine; Sulfanilamide; Tilmicosin; Tulathromycin; Tylosin; Zeranol; Zilpaterol drug analytes determined in the 10 real samples provided. As shown in the table, the use of a 5 min shake gave the highest concentrations 17 out of the 26 instances when a drug was determined in the samples.…”

Liquid Chromatography-Mass Spectrometry in the Analysis of Pesticide Residues in Food

“…Its separation efficiency, up to 40,000, considerably exceeds the separation efficiency of the quadrupole analyzer. In the analysis of pesticide residues in food, the time-of-flight analyzer is mainly used to confirm the presence of the compounds of interest in matrices such as fruit and vegetables (Mezcua et al 2009;Taylor et al 2008), honey and meat (Mol et al 2008), fruit beverages GarciaReyes et al 2008), and wine (Perez-Ortega et al 2012).…”

Determination of Pesticides in Grape Juices by QuEChERS and Liquid Chromatography-Tandem Mass Spectrometry

“…Crops are treated with pesticides and against pests and may leave residues in products of plant. 1 Thus, determination of pesticide residues in food matrices has become a necessity in view of the toxicity and stability of these xenobiotics. 2 Due to the low detection levels required by the regulatory bodies and the complex nature of the matrices, which the target compounds are present, the trace level detection and identification with prior efficient sample preparation are important aspects in the analytical method.…”