双水相萃取-高效液相色谱法分析红小豆中酰胺除草剂

建立以硫酸铵-乙醇为基础的双水相萃取法,在红小豆中萃取分离富集乙草胺、丁草胺、敌稗、异丙甲草胺4 种酰胺类除草剂的方法。采用高效液相色谱法对4 种除草剂进行分析测定。在双水相萃取过程中,上相富醇溶液的极性更接近于同一有机溶剂中除草剂的极性。下相盐溶液能有效沉淀蛋白质和脂肪。考察前处理条件,最终选择硫酸铵-乙醇体系双水相体系类型、25%乙醇、28%硫酸铵、35 ℃、1 min超声萃取时间为最佳前处理条件。由于避免了有毒有机溶剂,本方法是一种环境友好的方法。乙草胺、丁草胺、敌稗、异丙甲草胺的检测限分别为3.5、7.1、4.6、5.8 μg/kg。在加标量为10 μg/kg和100 μg/kg水平下,4 种酰胺除草剂的平均回收率范围为86.1%～95.9%,相对标准偏差≤4.5%。     

Aflatoxin M1 and B1 in Colombian milk powder and estimated risk exposure

ABSTRACT

Aflatoxin M₁ (AFM₁) and aflatoxin B₁ (AFB₁) were determined in 51 milk powder samples purchased from different grocery stores located in the Caribbean region of Colombia. Analysis was conducted using QuEChERS extraction and high-performance liquid chromatography with fluorescence detection. Results from the analytical method showed recovery ranges from 65% to 110% and relative standard deviations lower than 20%. AFM₁ was detected in 100% of the milk samples (0.20–1.19 µg/kg) and 55% exceeded the maximum level in milk (0.5 µg/kg) set by the Colombian and European regulations. AFB₁ was not detected in any of the analysed samples. Considering the measured contamination the maximum AFM₁ level that can be ingested by consumption of milk powder is 0.007–0.013 µg/person/day. These values are above the average dietary intake estimated in Latin America according to the Joint FAO/WHO Expert Committee, which is 0.0035 µg/person/day.     

Detection of 20 phthalate esters in breast milk by GC-MS/MS using QuEChERS extraction method

ABSTRACT

A detection method for 20 different phthalate esters (PAEs) in breast milk analyzed by quick, easy, cheap, effective, rugged, and safe (QuEChERS) clean-up with five internal standards and quantitative GC–MS/MS was established. This method can effectively remove interfering substances such as lipids and fatty acids from breast milk using acetonitrile as the extraction solvent and PSA/C18 as clean-up materials. The 20 PAEs had a linear range of 5.0–500.0 µg/L and recoveries of 83.3–123.3% with RSDs of 0.2–7.6% (n = 6). The method detection limits (LODs) were 0.004–1.3 µg/kg. Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Diisobutyl phthalate (DIBP), Di-n-butyl phthalate (DBP) and bis(2-ethylhexyl) phthalate (DEHP) were detected in the 35 breast milk samples, with median levels of 1.2, 6.8, 7.3, 32.9 and 13.6 μg/kg, respectively, and the concentrations of 20 PAEs ranged between 0.5 and 137.3 μg/kg. This is a fast, simple, sensitive and accurate method for the detection of 20 PAEs in breast milk or dairy products.     

A new selective liquid membrane extraction method for the determination of basic herbicides in agro-processed fruit juices and Ethiopian honey wine (Tej) samples

Supported liquid membrane (SLM) extraction was optimised for trace extraction and enrichment of selected triazine herbicides from a variety of agro-processed fruit juices and Ethiopian honey wine (Tej) samples. In the extraction process, a 1:1 mixture of n-undecane and di-n-hexylether was immobilised in a thin porous PTFE membrane that forms a barrier between two aqueous phases (the donor and acceptor phases) in a flow system. The extracts constitute the selectively enriched analytes collected from the acceptor phase and were analysed by transferring to a HPLC-UV system using a diode array detector at 235?nm. High enrichment factors were obtained with very good repeatability of results, and the detection limit was lower than 3.00?µg l^?1 for ametryn in apple juice. The optimised method showed very good linearity of over 50–500?µg l^?1 with a correlation coefficient of >0.990 or better for triplicate analysis. All chromatograms gave well resolved peaks with no interfering peaks at the retention times of the selected triazines, showing high selectivity of the SLM extraction method in combination with HPLC-UV for the selected matrices. The optimised method can be used as an alternative solventless extraction method for microgram-level extraction of other triazine herbicides and a variety of pesticides from liquid and semi-liquid environmental, biological and food matrices.     

A deep eutectic solvent based liquid phase microextraction for the determination of caffeine in Turkish coffee samples by HPLC-UV

ABSTRACT

A novel liquid-phase microextraction procedure for the determination and extraction of caffeine using a deep eutectic solvent based liquid-phase microextraction method (DES-LPME) was developed. A deep eutectic solvent consisting of choline chloride-phenol (1:3) and tetrahydrofuran as a dilution solvent were used for the extraction of caffeine from Turkish coffee samples. The quantitative recoveries were obtained when the DES volume was 400 µL, and the volume of tetrahydrofuran that was used as an emulsifier solvent was 800 µL. The limit of detection and the limit of quantification were found to be 0.12 and 0.40 µg mL^?1, respectively. Linear dynamic range was 0.5–100 µg mL^?1, and coefficient of determination (R²) was 0.9998. The relative standard deviation (RSD) was 2.20% when the standard solution concentration was 1.0 µg mL^?1. The fact that the determination coefficient obtained from the calibration curve was greater than 0.9998 gives information about the accuracy of the method. Also, in order to determine the accuracy of the developed method, selected coffee samples were spiked with 25 and 50 µg mL^?1 caffeine.     

A multi-class multi-residue method for the analysis of polyether ionophores,tetracyclines and sulfonamides in multi-matrices of animal and aquaculture fish tissues by ultra-high performance liquid chromatography tandem mass spectrometry

ABSTRACT

An ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) based multiclass multi-residue method for the simultaneous analysis of 5 polyether ionophores, 4 tetracycline and 10 sulfonamides in animal and aquaculture fish tissues was developed and validated. Sample extraction and clean-up were based on a modified QuEChERS method. The method was validated using an in-house validation based on performance characteristics modified from Commission Decision 2002/657/EC. Both matrix effect and uncertainties associated with sample preparation and instrumental analysis were minimised by the use of matrix-matched calibrations. Recoveries of analytes were generally satisfactory and typically fell between 80% and 113%. The repeatability and intermediate reproducibility measured as relative standard deviations were in most cases less than 15% (n = 63). The decision limit (CCα) and detection capability (CCβ) ranged from 110.7 to 125.8 and 121.5 to 151.7 µg kg^?1 for tetracyclines, 113.4 to 118.3 and 116.8 to 126.5 µg kg^?1 for sulfonamides and 50.8 to 52.4 and 51.5 to 55.6 µg kg^?1 for polyether ionophores, respectively. The method displayed its fitness for purpose through satisfactory results obtained in international proficiency testing schemes. The method was applied to animal and aquaculture fish tissues obtained from different sources in South Africa. Polyether ionophores were predominantly detected in samples in the range 4.26–290.10 µg/kg. Oxytetracycline was found in one porcine liver sample; however, none of the targeted analytes were present above the detection limit in the aquaculture samples.     

Acrylamide in deep-fried snacks of India

Acrylamide content in deep-fried snacks from 20 different production sites of South Indian province of Kerala (80 samples representing 4 important product categories) were determined using a modified high performance liquid chromatography (HPLC)–diode array detector (DAD) method. The limit of detection and the limit of quantification for this method were 1.04 and 3.17 μg/kg, respectively. The mean recoveries of acrylamide obtained by using spiked samples ranged between 90% and 103%, which shows good extraction efficiency. Acrylamide concentrations in the four groups of snacks ranged from 82.0 to 4245.6 µg/kg for potato chips, 46.2–2431.4 µg/kg for jack chips, 24.8–1959.8 µg/kg for sweet plantain chips and 14.7–1690.5 µg/kg for plantain chips. These are the most widely consumed snacks in South India, and the results revealed reasonable levels of acrylamide in these foods, which indicated the general risk of consumer exposure.     

Improved sensitivity of ochratoxin A analysis in coffee using high-performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS)

A novel and sensitive method utilising high-performance liquid chromatography coupled to triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS) was developed in order to analyse the content of ochratoxin A (OTA) in coffee samples. The introduction of the triple-stage MS scanning mode (MS³) has been shown to increase greatly sensitivity and selectivity by eliminating the high chromatographic baseline caused by interference of complex coffee matrices. The analysis included the sample preparation procedure involving extraction of OTA using a methanol–water mixture and clean-up by immunoaffinity columns and detection using the MS³ scanning mode of LC-QqQLIT-MS/MS. The proposed method offered a good linear correlation (r² > 0.998), excellent precision (RSD < 2.9%) and recovery (94%). The limit of quantification (LOQ) for coffee beans and espresso beverages was 0.010 and 0.003 µg kg^?1, respectively. The developed procedure was compared with traditional methods employing liquid chromatography coupled to fluorescent and tandem quadrupole detectors in conjunction with QuEChERS and solid-phase extraction. The proposed method was successfully applied to the determination of OTA in 15 samples of coffee beans and in 15 samples of espresso coffee beverages obtained from the Latvian market. OTA was found in 10 samples of coffee beans and in two samples of espresso in the ranges of 0.018–1.80 µg kg^?1 and 0.020–0.440 µg l^?1, respectively. No samples exceeded the maximum permitted level of OTA in the European Union (5.0 µg kg^?1).     

SCREENING AND QUANTIFICATION OF AFLATOXINS AND OCHRATOXIN A IN DIFFERENT CEREALS CULTIVATED IN ROMANIA USING THIN-LAYER CHROMATOGRAPHY-DENSITOMETRY

ABSTRACT

The main focus of our study was to implement a rapid, inexpensive and reliable method that could be utilized to check the cereals for safety (i.e., screening for total aflatoxins, as well as individual B₁, B₂, G₁, G₂ aflatoxins and ochratoxin A). We developed a protocol by which we were able to isolate mycotoxins from cereals collected from different regions of Romania. After extraction in chloroform, the mycotoxins were separated by thin‐layer chromatography (TLC) and quantified using densitometry. Forty‐three samples of different cereals (wheat, maize, rye and Triticale) were analyzed. Twenty‐five of the 43 samples (58.14% of the total number) were found to be contaminated with different mycotoxins in various concentrations: aflatoxin B₁ (1.6–5.7 µg/kg), aflatoxin B₂ (0.89–4 µg/kg), aflatoxin G₁ (1.2–5.76 µg/kg), aflatoxin G₂ (0.96–3.4 µg/kg) and/or 4.3–30 µg/kg ochratoxin A. The concentration of total aflatoxin contamination ranged from 11.2 to 10.8 µg/kg. Among the different cereals, the highest number of contaminated samples was found to be in the wheat samples (62.5%). The method outlined in this study has been adopted already by our laboratory for current analyses of mycotoxins. The results obtained using this method is in compliance with the strict regulatory guidelines developed both in Romania, as well as in the European Union.

PRACTICAL APPLICATIONS

Thin‐layer chromatography (TLC) is a rapid, inexpensive and convenient method that can be used routinely to screen for mycotoxins. This article describes the detailed procedures for the extraction, purification and quantification of aflatoxins and ochratoxin A, using TLC. Using this method one can identify concomitantly five different mycotoxins and by coupling it with densitometry a quantitative determination is also possible. Therefore, this could become a routine technique in regional laboratories responsible for checking agrifood safety.     

Non-isoflavone phytoestrogenic compound contents of various legumes

Widely consumed legumes including chickpeas, red kidney beans, haricot beans, yellow lentils, red lentils and green lentils were analysed to determine the content of non-isoflavone phytoestrogenic compounds such as quercetin, rutin, apigenin, coumestrol and lignan (matairesinol and secoisolariciresinol). Methanolic extracts obtained by ultrasound-assisted extraction were analysed by the triple quadrupole LC–MS/MS. Red kidney beans were the best source of quercetin (603.2 ± 307.2 μg/kg) and rutin (73.4 ± 14.0 μg/kg). Apigenin and secoisolariciresinol contents were the highest in yellow lentils (18.5 ± 0.84 μg/kg) and haricot beans (451.9 ± 192.2 μg/kg), respectively. Coumestrol contents of haricot beans (18.5 ± 1.45 μg/kg) and red kidney beans (18.5 ± 1.26 μg/kg) were equal to each other, and these were determined as the highest coumestrol content values. The best sources of matairesinol occurred in green lentils (28.2 ± 0.18 μg/kg) and chickpeas (27.7 ± 1.83 μg/kg). Differences between contents of each sample of the same legume were significant and remarkable, especially for quercetin and secoisolariciresinol.     

Ochratoxin A contamination of coffee batches from Kenya in relation to cultivation methods and post-harvest processing treatments

This study set out to assess the relative importance of sound and unsound beans in a batch of coffee with regard to ochratoxin A (OTA) contamination. Initially, unsound beans were found to account for 95% of contamination in a batch of coffee, whatever the methods used for post–harvest processing. It was also found that beans displaying traces of attacks by Colletotrichum kahawae were the greatest contributors to OTA contamination. In a second stage, the study compared the contamination of sound beans with that of beans attacked by Colletotrichum kahawae. On average, beans attacked by Colletotrichum kahawae had a statistically higher OTA content than sound beans (18.0 µg kg^?1 as opposed to 1.2 µg kg^?1). In addition, the average OTA content in unsound beans varied depending on growing conditions.     

Validation of a gold standard method for iodine quantification in raw and processed milk,and its variation in different dairy species

Adequate milk consumption significantly contributes to meeting the human iodine recommended daily intake, which ranges from 70 µg/d for infants to 200 µg/d for lactating women. The fulfilment of iodine recommended daily intake is fundamental to prevent serious clinical diseases such as cretinism in infants and goiter in adults. In the present study iodine content was measured in raw and processed commercial cow milk, as well as in raw buffalo, goat, sheep, and donkey milk. Iodine extraction was based on 0.6% (vol/vol) ammonia, whereas iodine detection and quantification were carried out through an inductively coupled plasma mass spectrometer analyzer. Among processed commercial cow milk, partially skimmed pasteurized milk had the greatest iodine content (359.42 µg/kg) and raw milk the lowest (166.92 µg/kg). With regard to the other dairy species, the greatest iodine content was found in raw goat milk (575.42 µg/kg), followed by raw buffalo (229.82 µg/kg), sheep (192.64 µg/kg), and donkey milk (7.06 µg/kg). Repeatability of milk iodine content, calculated as relative standard deviation of 5 measurements within a day or operator, ranged from 0.96 to 1.84% and 0.72 to 1.16%, respectively. The overall reproducibility of milk iodine content, calculated as relative standard deviation of 45 measurements across 3 d of analyses and 3 operators, was 4.01%. These results underline the precision of the proposed analytical method for the determination of iodine content in milk.     

Multi-element determination in some foods and beverages using silica gel modified with 1-phenylthiosemicarbazide

ABSTRACT

1-Phenylthiosemicarbazide bonded modified silica gel (PTC-SG) was synthesised and characterised by FTIR, SEM and elemental analysis for a novel separation/preconcentration of multiple elements based on solid phase extraction. The analytical parameters including pH of solutions, amounts of PTC-SG, flow rates of sample, eluent type and sample volume were optimised. The adsorption capacities of PTC-SG were found to be 7.9, 6.4, 6.3, 8.3, 7.2, 8.9 and 6.6 mg/g for Cu(II), Cd(II), Pb(II), Co(II), Cr(III), Ni(II) and Mn(II), respectively. The limit of detection (LOD) was calculated as 3x the standard deviation(s) of the reagent blank (k = 3, N = 21) and the LOD values were obtained to be 0.98 µg L^?1 (Cu), 0.65 µg L^?1 (Cd), 0.57 µg L^?1 (Pb), 1.12 µg L^?1 (Co), 1.82 µL^?1 (Cr), 1.67 µg L^?1 (Ni) and 0.55 µg L^?1 (Mn). Certified reference materials were used to test the validation of the present method. The new solid phase extraction method was successfully applied to determination of the amount of multiple elements in food and beverage samples.     

A Rapid High-Performance Liquid Chromatography Photodiode Array Detection Method to Determine Phenolic Compounds in Mung Bean (Vigna radiata L.)

A fast method was developed for simultaneous detection and quantification of 12 phenolic compounds in mung bean, using reversed phase high-performance liquid chromatography. The method was optimized for mobile phase combination, elution gradient, detection wavelength, and solvent extraction. All the phenolic compounds (gallic acid, neochlorogenic acid, catechin, chlorogenic acid, caffeic acid, p-coumaric acid, t-ferulic acid, vitexin, isovitexin, myricetin, quercetin, and kaempferol) were eluted for 18 min and recovered within a limit as per International Council for Harmonization guidelines. The method showed good linearity with correlation coefficient of 0.998. The limit of detection and quantification of all the compounds ranges from 0.27 ± 0.01 to 3.65 ± 0.3µg/mL and 0.91 ± 0.1 to 12.17 ± 0.9µg/mL, respectively. Vitexin (28.10 ± 0.20 to 29.60 ± 0.6 mg/100 g raw material) and isovitexin (34.09 ± 0.14 to 36.83 ± 0.82 mg/100 g raw material) were the major phenolic compounds along with other phenolic compounds found in mung beans.     

Development of a chemometric-assisted deep eutectic solvent-based microextraction procedure for extraction of caffeine in foods and beverages

ABSTRACT

In this research article, a novel and green deep eutectic solvent-based microextraction (DES-ME) procedure based on chemometric-assisted (CA) optimization was developed for the extraction of caffeine in foods and beverages prior to its spectrophotometric determination. Ultrasound was used to accelerate the extraction of caffeine. Deep eutectic solvents (DES), prepared in an ultrasonic bath at 20–60 min for 60–80°C, were used as extraction solvents. The important experimental variables (pH, DES amount, temperature, sonication time and metal concentration) were modelled and optimized using response surface methodology (RSM) based on central composite design (CCD). Under the optimum conditions, the proposed method allowed the determination of caffeine with limits of detection (LOD, 3s_blank/m) and quantification (LOQ, 3s_blank/m) of 7.5 and 25.0 µg L^?1, respectively. For 40 µg L^?1 and 100 µg L^?1 of caffeine (n = 5), relative standard deviations (RSDs%) and recoveries% were 1.2–1.6% and 96.7–98.2%, respectively. Validation studies (accuracy, precision, trueness, reliability and selectivity) of the method were performed before the analysis of real samples. The results showed that the combination of the CCD with the DES-ME can be considered as a new perspective for the extraction and determination of caffeine in foods and beverages.     

Comparison of extraction solvents and conditions for herbicide residues in milled rice with liquid chromatography-diode array detection analysis (LC-DAD)

Different extraction procedures and clean-up methods were compared in order to develop a sample preparation procedure for the multi-residue analysis of six post-emergence herbicides (metsulfuron methyl, bensulfuron methyl, pyrazosulfuron ethyl, bentazone, bispyribac sodium and cyhalofop butyl) in rice grains followed by liquid chromatography-diode array detection (LC-DAD). Optimum results were obtained dispersing milled rice grain in water, followed by the addition of 1% acetic acid in acetonitrile, MgSO₄ and sodium acetate as a modification of the quick, easy, cheap, effective, rugged and safe (QuEChERS) method but no primary and secondary amine (PSA) sorbent was added due to the acidic nature of the herbicides. The method was further expanded to other post-emergence herbicides (quinclorac, clomazone and propanil). Except for quinclorac, which cannot be analysed with this method, the recoveries of the other eight herbicides were in the range 73–111%, with relative standard deviations lower than 12%. Limits of detection (LODs) ranged from 0.03 to 0.08 mg kg^?1. A single analyst can extract twelve samples in 4 h. The method presented here allows the simultaneous residue determination of the most common post-emergence herbicides employed in cultivating rice. It is simple, rapid, sensitive, and can be applied routinely to polished rice grain herbicide residue analysis.     

Fast and simple determination of moroxydine residues in pig and chicken samples by ultra-performance liquid chromatography-tandem mass spectrometry

ABSTRACT

A general solid-phase extraction (SPE) method using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the determination of moroxydine residues in pig and chicken samples has been developed. After extraction and purification of real samples, moroxydine residues were detected using a hydrophobic interaction liquid chromatography column with an optimised mobile phase composition. The extraction reagents, the kind of SPE columns and the type of eluents were optimised to achieve the maximum extraction efficiency. The matrix effects from the animal tissue influenced the quality of the quantitative data obtained. Under the optimised conditions, the moroxydine residues in pig and chicken samples spiked at three levels (1.0 μg/kg, 5.0 μg/kg and 10.0 μg/kg) were determined with good recoveries (61.5%–105.4%) and adequate relative standard deviations (3.2%–13.0%). In pig and chicken samples, the limit of detection (LOD) was 0.3 μg/kg, and the limit of quantification (LOQ) was 1.0 μg/kg. A sufficiently linear relationship in the range of 1.0 μg/kg–20.0 μg/kg was achieved with a good correlation coefficient (R² ≥ 0.99).     

Development of a screening analytical method for the determination of non-dioxin-like polychlorinated biphenyls in chicken eggs by gaschromatography and electron capture detection

ABSTRACT

A sensitive and reproducible screening analytical method is here proposed for the determination of six non dioxin-like polychlorinated biphenyls (NDL-PCBs, congener 28, 52, 101, 138, 153, 180) in chicken eggs based on accelerated solvent extraction (ASE) procedure for the fat extraction and determination, a solid phase extraction (SPE) sample clean-up process, and a gas chromatography – electron capture detection (GC-ECD) analysis. The optimized chromatographic separation, in less than 25 min, returned good responses for the six NDL-PCBs in the range of 2.5–60.0 µg L^?1, with correlation coefficients always higher than 0.9995. Instrumental limits of detection were between 0.08–0.35 µg L^?1, corresponding to 0.05 and 0.23 ng g^?1 fat in the matrix, while method detection limits, calculated on spiked egg samples, ranged from 1.6 to 3.5 ng g^?1 fat. The method has been extensively validated in terms of selectivity, sensitivity, recovery, precision, ruggedness and measurement uncertainty, following the European Directives.     

Tetracycline antibiotics transfer from contaminated milk to dairy products and the effect of the skimming step and pasteurisation process on residue concentrations

The presence of antibiotics in raw milk and milk derivatives poses a threat to human health and can negatively affect the dairy industry. Therefore, the main object of this study was to investigate the transfer of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from raw, experimental milk contaminated with tetracyclines (TCs) to different dairy products: cream, butter, buttermilk, sour milk, whey, curd and cheese. Additionally the effect of the skimming process on TCs concentrations was tested, as well as the influence of low-temperature long-time pasteurisation. The analyses of TCs in milk and dairy products were performed by an LC-MS/MS method. In order to determine TCs residues in dairy products, an analytical method was developed with the same extraction step for all matrices. TCs molecules were inhomogenously distributed between the milk derivative fractions. The highest concentrations were determined in curd and cheese in the ranges 320–482 µg/kg and 280–561 µg/kg, respectively. Low levels of TCs in butter and whey were observed (11.8–41.2 µg/kg). TCs were found in sour milk (66.0–111 µg/kg), cream (85.0–115 µg/kg) and buttermilk (196–221 µg/kg) at much higher levels than in butter and whey, but lower than in curd and cheese. During the skimming process, the highest yield of cream was obtained after the raw milk was held at 2–8°C for 24 h. The differences in concentrations of TCs between whole milk and skimmed milk, expressed as percentages of recovery, were below 19% (recoveries in excess of 81%). The highest content was observed in milk and cream skimmed at 2–8°C. The degradation percentages for TCs during the pasteurisation process (63°C for 30 min) were below 19%.     

HPLC-DAD analysis of florfenicol and thiamphenicol in medicated feedingstuffs

ABSTRACT

A simple and reliable method using liquid chromatography with diode array detector was developed for the simultaneous determination of florfenicol and thiamphenicol in medicated feed. The analytes were extracted from the minced feed with methanol and ethyl acetate (1:1, v/v). Next, the extract was further cleaned up by dispersive solid phase extraction using anhydrous magnesium sulfate, PSA and C18 sorbents. Finally, 1 mL of extract was evaporated, the residue resuspended in Milli-Q water, and filtered. The method was validated in-house at medicated levels, in the concentration range 10–300 µg/mL (50–1500 mg/kg). Values of <6.5% and <6.0% were found, respectively, for repeatability and within-laboratory reproducibility. The LODs for the two fenicols were 2.4–5.3 mg/kg, while the LOQs were 3.8–5.6 mg/kg. The expanded uncertainty was estimated to be in the range of 10.0–14.5%, depending on the analyte. Recoveries varied from 81.7% to 97.5%. The methodology was applied to the analysis of animal feedingstuffs collected from poultry and pig farms.