火麻油中五种大麻素的HPLC同时检测

火麻油中含有大麻二酚酸（CBDA）、大麻二酚（CBD）、大麻酚（CBN）、Δ9-四氢大麻酚（THC）、四氢大麻酚酸（THCA）等多种大麻素。本文充分考虑其基质的特点,研究火麻油中5种大麻素提取的样品的快捷制备方法,通过优化色谱条件,实现待测组分与基质中杂质峰的有效分离,建立火麻油中五种大麻素的HPLC同时检测方法,并采用精密度实验、重复性实验以及加标回收率实验等对方法加以验证。结果表明,五种大麻素在0.5~50 μg/mL范围内有良好的线性关系,定量限（LOQ,S/N=10）均在0.33~0.80 mg/kg之间,回收率在77.1%~103.3%,相对标准偏差RSD≤4.7%。通过对国内4个产地的实际火麻油样品进行检测,发现其中均含有少量的大麻素,其中THC含量均少于0.3%,但是部分产品的THC含量比欧盟国家规定的上限高,存在一定的安全风险。本文所发展的方法为相关检测方法标准的建立奠定了方法学基础。     

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.     

QuEChERS结合气相色谱-三重四极杆串联质谱法快速测定地参中63种农药残留

采用QuEChERS前处理技术结合气相色谱-三重四极杆串联质谱法（GC-MS/MS）对不同产地的10批地参中的63种农药残留进行测定。样品用1%醋酸-乙腈溶液和QuEChERS萃取盐包提取,经1.2 g硫酸镁、400 mg N-丙基乙二胺（PSA）及200 mg石墨化炭黑（GCB）净化,在选择反应监测模式（SRM）下检测,基质匹配内标法定量。结果显示,63种农药在5～500 ng/mL质量浓度范围内线性关系良好,相关系数（R2）均＞0.996 4;在0.05 mg/kg、0.25 mg/kg和0.75 mg/kg 3个添加水平下,各农药化合物加标回收率为71.5%～120.4%,方法的相对标准偏差（RSD）为0.12%～9.70%;仪器精密度试验结果RSD为1.93%～5.06%;检出限（LOD）为0.5～3.6 μg/kg,定量限（LOQ）为1.7～12.0 μg/kg。不同产地地参均不同程度检出5种农药残留,包括氯菊酯、丙环唑、氯唑磷、苯霜灵和肟菌酯。     

Method development and validation for low-level propineb and propylenethiourea analysis in baby food,infant formula and related matrices using liquid chromatography-tandem mass spectrometry

ABSTRACT

Two simple, selective and rugged liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods were developed and validated for determination of propineb and propylenethiourea (PTU) in infant formula, fruit-based and cereal-based baby food and raw materials used in production of infant formula, including carbohydrates, protein isolates, vegetable oils and emulsifiers. The sample preparation procedure for propineb analysis was based on streamlined derivatisation to form and stabilise the target analyte (propylenebisdithiocarbamate-dimethyl), followed by extraction using a modified QuEChERS procedure with a dispersive solid phase extraction (d-SPE). The PTU determination employed an aqueous extraction with optimised protein precipitation and single-step SPE clean-up. To achieve maximum sensitivity, electrospray ionisation and atmospheric-pressure chemical ionisation were employed for LC-MS/MS analysis of propineb and PTU, respectively. Validation of the developed methods was performed in accordance with Document SANTE/11813/2017. Mean recoveries were in the range of 86–120% for propineb and PTU, respectively, with interday and intraday repeatabilities below 13%. A limit of quantification (LOQ) of 0.003 mg kg^–1 was validated for most of the evaluated analyte/sample matrix combinations with the exception of PTU in soy protein isolate and soybean oil, for which an LOQ of 0.01 mg kg^–1 was obtained. This is the first report that provides validated methods for monitoring propineb and PTU in infant formula and baby foods at concentrations compliant with the maximum residue levels established in the EU legislation.     

QuEChERS-超高效液相色谱-串联质谱法检测禽源性食品中氟虫腈及其代谢物

建立QuEChERS-超高效液相色谱-串联质谱检测禽源性食品中氟虫腈及其代谢物的方法。采用Plackett-Burman试验和Box-Behnken试验筛选和优化QuEChERS前处理方法中的显著影响因素。最终优化条件：样品用乙腈超声提取,后用NaCl、无水MgSO4盐析分层,提取液再用碳十八键合锆胶（Z-Sep+）、多壁碳纳米管进行净化,净化液用超高效液相色谱-串联质谱分析测定,采用基质加标曲线进行定量测定。结果表明,在鸡蛋、鸡肉、鸡肝基质中氟虫腈、氟甲腈、氟虫腈砜、氟虫腈亚的平均加标回收率在78.9%～113.5%之间,相对标准偏差在2.10%～7.60%之间,检出限在0.1～0.2 μg/kg之间,定量限为0.5 μg/kg。此方法可有效降低禽源性食品中基质效应,具有高灵敏度、精密度、准确度,可用于禽类食品中氟虫腈及其代谢物残留的快速定量测定。     

杀扑磷降解产物的鉴定及在蔬菜中残留量的检测

以杀扑磷为研究对象,分析鉴定了自然条件下水中杀扑磷的降解产物和市购杀扑磷中农药成分,采用QuEChERS前处理方法,建立了蔬菜中杀扑磷及降解物残留量的检测方法。结果表明,杀扑磷在水中的降解产物为牛津郡杀扑磷,市购的杀扑磷农药中除杀扑磷外,其降解产物牛津郡杀扑磷含量高达1.5 g/kg;建立的检测方法在1~100 ng/mL内线性良好(R²≥0.99),在定量限、3倍定量限和10倍定量限的加标水平下,回收率为62.9%~97.2%,RSD为1.6%~10.0%。该方法简便、快速、灵敏度高,适用于蔬菜中杀扑磷及其牛津郡杀扑磷的测定。     

Multiclass method for fast determination of veterinary drug residues in baby food by ultra-high-performance liquid chromatography–tandem mass spectrometry

A simple and rapid multiresidue method for the determination of different veterinary drug residues in meat-based baby food (MBF) and powdered milk-based infant formulae (PMIF) has been developed. The method involves an extraction procedure based on buffered QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology, without any further clean-up step, followed by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method has been validated in two baby food matrices (MBF and PMIF) at three different concentration levels, obtaining suitable recoveries and precision (inter and intra-day precision) values. Quantification was carried out using matrix-matched standard calibration. Furthermore, the decision limit (CCα) and the decision capability (CCβ) were evaluated, ranging from 0.5 to 16.2 μg/kg and from 1.2 to 22.4 μg/kg, respectively. Finally, the method was applied to the analysis of several kinds of baby food samples and traces of some veterinary drugs were detected.     

Determination of Pesticide Residues in Soy-Based Beverages Using a QuEChERS Method (with Clean-Up Optimized by Central Composite Design) and Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry

Soybean production is responsible for a great amount of pesticides applied in Brazil. In the last years, an increase of soy-based beverage consumption and a higher concern about pesticide residues in food occurred. A simple, fast, and efficient multiresidue method based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was developed for simultaneous determination of 39 pesticides and two plant growth regulators in soy-based beverages by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The clean-up procedure was established based on central composite design (CCD), using response surface methodology (RSM). For the optimization of the clean-up step, different amounts of sorbents in dispersive solid phase extraction (d-SPE) were evaluated. Validation results were satisfactory, considering that the optimized method presented recoveries between 70 and 112 %, with RSD lower than 19 % for spike levels between 10 and 50 μg L^?1. The method limit of detection (LOD) and quantification (LOQ) ranged from 3 to 8 and 10 to 25 μg L^?1, respectively. The proposed method combines the advantages of QuEChERS and UHPLC-MS/MS and proved to be suitable for the pesticide multiresidue determination in soy-based beverages in routine laboratory analyses.     

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.     

Rapid Simultaneous Screening and Detection of 12 Anticoagulant Rodenticides in Food by Ultra-performance Liquid Chromatography-Triple Quadrupole/Linear Ion Trap Tandem Mass Spectrometry

A rapid analytical method for the simultaneous screening and detection of 12 anticoagulant rodenticides in food samples was established based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation method using an ultra-performance liquid chromatography-triple quadrupole/linear ion trap tandem mass spectrometry (UPLC-QTrap-MS/MS). Food samples were extracted and purified with modified QuEChERS method. The 12 anticoagulant rodenticides (warfarin, brodifacoum, difethialone, coumachlor, coumatetralyl, bromadiolone, chlorophacinone, difenacoum, diphacinone, pindone, valone, and flocoumafen) and the internal standard (warfarin-D₅) were separated within 6 min using an ACQUITY UPLC BEH-C18 column (1.7 μm, 2.1 mm × 50 mm) and gradient elution with the mobile phase consisting of 5 mM ammonium acetate formate buffer and acetonitrile. The multiple reaction monitoring-information dependent acquisition-enhanced product ion (MRM-IDA-EPI) scanning was employed for detection. The calibration curves were linear (R ² > 0.99) for all the compounds. The mean recoveries for the 12 analytes at three spiked levels (1× LOQ, 5× LOQ, and 10× LOQ) were in the range of 79.5–113.2% with RSDs of 1.8–13.2%.The limits of detection (LOD) for the 12 rodenticides ranged from 0.01 (warfarin) to 0.05 μg/kg (diphacinone). The limit of quantification (LOQ) for the 12 rodenticides was between 0.02 (warfarin) and 0.10 μg/kg (diphacinone). The developed method was more straightforward, less time and labor intensive, and more sensitive, selective, and accurate for screening multiple anticoagulant rodenticides, and it was successfully used in several poisoning cases.     

Multiclass mycotoxin analysis in edible oils using a simple solvent extraction method and liquid chromatography with tandem mass spectrometry

ABSTRACT

A simple and rapid method for the simultaneous determination of 11 mycotoxins – aflatoxins B₁, B₂, G₁ and G₂; fumonisins B₁, B₂ and B₃; ochratoxin A; zearalenone; deoxynivalenol; and T-2 toxin – in edible oils was established using liquid chromatography tandem mass spectrometry (LC-MS/MS). In this study, QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe), QuEChERS with dispersive liquid–liquid microextraction, and solvent extraction were examined for sample preparation. Among these methods, solvent extraction with a mixture of formic acid/acetonitrile (5/95, v/v) successfully extracted all target mycotoxins. Subsequently, a defatting process using n-hexane was employed to remove the fats present in the edible oil samples. Mass spectrometry was carried out using electrospray ionisation in polarity switching mode with multiple reaction monitoring. The developed LC-MS/MS method was validated by assessing the specificity, linearity, recovery, limit of quantification (LOQ), accuracy and precision with reference to Commission Regulation (EC) 401/2006. Mycotoxin recoveries of 51.6–82.8% were achieved in addition to LOQs ranging from 0.025 ng/g to 1 ng/g. The edible oils proved to be relatively uncomplicated matrices and the developed method was applied to 9 edible oil samples, including soybean oil, corn oil and rice bran oil, to evaluate potential mycotoxin contamination. The levels of detection were significantly lower than the international regulatory standards. Therefore, we expect that our developed method, based on simple, two-step sample preparation process, will be suitable for the large-scale screening of mycotoxin contamination in edible oils.     

Validation data for HPLC/FLD determinations of ochratoxin A in red paprika and black pepper adopting a one-step clean-up procedure

Validation data for the determination of ochratoxin A (OTA) in two spice matrices, red paprika and black pepper, were obtained for samples prepared with a simplified single-step clean-up column. Extracts of finely ground samples of red paprika and black pepper were prepared and applied to a Mycosep® 229 Ochra clean-up column. The purified extract was then subjected to HPLC/FLD analysis. The relative standard deviation for repeatability (RSDr) of the method was 11.8% for red paprika and 9.9% for black pepper. The limit of detection (LOD) value (three times the noise) was estimated as corresponding to the response of an extract derived from a blank matrix (previously washed) and spiked at 1.0 µg kg^?1. The limit of quantitation (LOQ) (three times LOD) was 3.0 µg kg^?1. The performance of the one-step column clean-up procedure appears to be a suitable alternative to commonly used clean-up techniques and allows the precise determination of OTA in two complex matrices.     

An Applicable Strategy for Improvement Recovery in Simultaneous Analysis of 20 Pesticides Residue in Tea

It is important to have a reliable method to analyze pesticides in tea, a beverage commonly consumed in Iran. A validated method was developed for the determination of 20 pesticides in tea based on QuEChERS sample preparation and capillary gas chromatography‐quadrupole mass spectrometry in selective ion monitoring mode (GC‐MS/SIM) using triphenyl methane (TPM) solution as an internal standard. We used fortified, extracted, and cleaned‐up tea samples instead of calibration standards for quantitation, which substantially reduced adverse matrix‐related effects and negative recovery affected by graphite carbon black (GCB) on pesticide analysis. The recovery of pesticides at 3 concentration (40, 60, and 240 ng/g) ranged from 79.5% to 111.4% (n = 3). The method had acceptable repeatability with RSDr < 20%. The limits of quantification (LOQ) for all pesticides were ≤20 ng/g. The analytical results of the proposed method were in good agreement with proficiency test results (FAPAS, 19116). The recoveries and repeatabilities were in accordance with the criteria set by SANCO Guideline. The validated method was suitable for the analysis of pesticides in tea.     

Analysing organochlorine pesticides in strawberry jams using GC-ECD,GC-MS/MS and QuEChERS sample preparation

This paper describes a comparison of adaptations of the QuEChERS (quick, easy, cheap, effective, rugged and safe) approach for the determination of 14 organochlorine pesticide (OCP) residues in strawberry jam by concurrent use of gas chromatography (GC) coupled to electron capture detector (ECD) and GC tandem mass spectrometry (GC-MS/MS). Three versions were tested based on the original QuEChERS method. The results were good (overall average of 89% recoveries with 15% RSD) using the ultrasonic bath at five spiked levels. Performance characteristics, such as accuracy, precision, linear range, limits of detection (LOD) and quantification (LOQ), were determined for each pesticide. LOD ranged from 0.8 to 8.9?µg?kg^?1; LOQ was in the range of 2.5–29.8?µg?kg^?1; and calibration curves were linear (r ^2?>?0.9970) in the whole range of the explored concentrations (5–100?µg?kg^?1). The LODs of these pesticides were much lower than the maximum residue levels (MRLs) allowed in Europe for strawberries. The method was successfully applied to the quantification of OCP in commercially available jams. The OCPs were detected lower than the LOD.     

高效液相色谱-串联质谱同时检测黑巧克力中的五种大麻酚

基于巧克力和大麻酚类物质的物理化学性质,本文通过对前处理方法和检测方法的优化,建立了一种巧克力中五种大麻酚的高效液相色谱-串联质谱检测方法。并通过精密度、重复性以及加标回收等实验对方法的有效性进行了验证。结果表明,五种大麻酚在0.05~5.0 μg/mL浓度范围内有良好的线性关系,线性相关系数R2≥0.997,定量限（LOQ,S/N=10）为0.15 mg/kg;日内和日间精密度的相对标准偏差RSDs值<5%,说明该方法具有良好的精密度和稳定性;在三个加标水平（1.25、2.50、5.00 mg/kg）下的回收率为91.8%~109.0%,RSDs<5%,说明该方法具有较高的准确性。本方法具有简单、快速、准确等优点,可以为建立巧克力中大麻酚类物质的检测方法标准奠定实验基础,同时为加强国际大麻酚添加食品进出口监管提供技术储备。     

二甲四氯异辛酯及其代谢物二甲四氯在玉米中的残留量及风险评估

目的 明确鲜食玉米和成熟期籽粒中2甲4氯异辛酯及其代谢物2甲4氯残的残留水平,评价其膳食摄入风险。方法 以改进的QuEChERS前处理方法同时提取玉米中2甲4氯异辛酯和2甲4氯残留物,分别用用气相色谱-串联质谱法和液相色谱-串联质谱法检测2甲4氯异辛酯和2甲4氯的残留量。结果 2甲4氯异辛酯和2甲4氯仪器最小检出量(LOD)分别为2×10_^-12 g和5×10_^-12 g;在鲜食玉米、成熟期籽粒的最小检出浓度( LOQ)均为0.005 mg/kg,整体回收率为71%~114%,相对标准偏差(RSD)为1.2%~7.2 %。结论 该方法的准确度和精密度良好,2甲4氯异辛酯在鲜食玉米中残留量为<0.005~0.032 mg/kg,成熟期籽粒中残留量为<0.005~0.022 mg/kg,均<0.05 mg/kg;代谢物2甲4氯在鲜食玉米、成熟期籽粒中的最终残留量均<0.005 mg/kg;玉米中2甲4氯异辛酯及其代谢物2甲4氯残的膳食风险较低。     

Development of multiresidue DLLME and QuEChERS based LC–MS/MS method for determination of selected neonicotinoid insecticides in honey liqueur

Honey liqueur is an alcoholic drink derived from honey and strong fruit brandy of suitable type, traditionally made in Serbia and other Balkan countries. Although European Union has regulated the levels of neonicotinoid insecticides in honey and pollen, there is an increased risk of the presence of these compounds in traditional products made from honey. The objective of this study was to develop an optimized LC–MS/MS analytical method with dispersive liquid–liquid microextraction (DLLME) and QuEChERS sample preparation procedures for analysis of seven neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in honey liqueur. The LC–MS/MS conditions were optimized to unequivocally provide good chromatographic separation, selectivity and specificity of developed method. The method was validated to fulfill the requirements of SANCO/12495/2011 for both sample pretreatment procedures providing results for accuracy (R, 69.2–113.4% for DLLME; 71.8–94.9% for QuEChERS), precision (RSD expressed in terms of repeatability (3.21–10.20% for DLLME; 4.19–12.81% for QuEChERS) and within-laboratory reproducibility (9.11–16.63% for DLLME; 11.32–16.40% for QuEChERS)), limits of detection (LOD, 0.5–1.5 μg L^− 1 for DLLME; 1.0–2.5 μg L^− 1 for QuEChERS) and quantification (LOQ, 1.0–5.0 μg L^− 1 for DLLME; 2.5–10.0 μg L^− 1 for QuEChERS). Matrix effects were compensated by the use of matrix-matched calibration. Analysis of real honey liqueur samples obtained from local markets showed the presence of clothianidin or thiacloprid in four of the analyzed samples, therefore implicating the necessity of ongoing control of this type of traditional product.     

Screening for twenty-eight target anabolic-androgenic steroids in protein supplements using QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry

ABSTRACT

Anabolic-androgenic steroids (AASs) are very potent muscle builders, and professional sportsmen often take protein supplements to improve their performance. Several studies have emphasised that protein supplements may contain undeclared AASs banned by the International Olympic Committee/World Anti-Doping Agency. The widespread occurrence and abuse of contaminated protein supplements is extremely dangerous because of their side effects. To minimise the chances of an unattended positive doping test or to avoid serious health problems, adequate screening methods for the detection of a wide range of steroids is essential. To address this requirement, a rapid and effective modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method was developed and validated to screen and quantify the simultaneous analysis of twenty-eight AASs in protein supplements using LC-MS/MS. The validated method was applied to 198 protein supplements collected from on-line and, off-line markets, and direct purchase from overseas between 2019 and 2020. Of the 198 samples, two samples contained testosterone and stanozolol at concentrations of 0.27 μg/g and 0.023 μg/g, respectively. In addition, 5α-hydroxylaxogenin was detected for the first time in three products purchased in Korea from overseas. The modified QuEChERS method was established and successfully applied to screen and determine AASs as a measure of continuous control and supervision in protein supplements.     

Comparison of Simple and Rapid Extraction Procedures for the Determination of Pesticide Residues in Fruit Juices by Fast Gas Chromatography–Mass Spectrometry

Three sample treatment methods, based on QuEChERS, solid-phase extraction (SPE) and solid-phase microextraction (SPME), were compared and evaluated in order to obtain the best conditions to determine pesticide residues in fruit juice by fast gas chromatography–mass spectrometry (single quadrupole GC-MS). Analysis were performed under selected ion monitoring, acquiring the three most abundant and/or specific ions for each analyte and using their relative intensity ratios as a confirmatory parameter. The 3 methodologies (QuEChERS, SPE and SPME) were validated taking 15 selected pesticides as model compounds, using commercial apple juice. QuEChERS procedure was based on the AOAC Official Method 2007.01, using acetonitrile (containing 1 % acetic acid) as extraction solvent and primary–secondary amine during the dispersive solid-phase extraction. Oasis hydrophilic–lipophilic balance cartridges were used for SPE, and polyacrylate fibers were used for direct immersion SPME procedure. Three isotopically labeled standards were added to the samples before extraction and used as surrogate standards. Validation parameters as recoveries, limits of detection, and limits of quantification (LOQ), as well as matrix effects and sample throughput, were obtained and compared for the three extraction procedures. QuEChERS was considered faster and led to the best quantitative results. In this way, validation was extended to up to 56 pesticides by applying QuEChERS in multi-fruit juice samples, obtaining LOQs ranging from 2 to 20 μg/L for most compounds. Accuracy and precision were evaluated by means of recovery experiments at two concentration levels (10 and 100 μg/L), obtaining recoveries between 70 and 120 % in most cases and relative standard deviations below 15 %. Finally, the QuEChERS method was applied to the analysis of commercial juices, including mango–apple, pineapple, grapefruit and orange.     

Study of ochratoxin A content in South Moravian and foreign wines by the UPLC method with fluorescence detection

In 2009–2010, 72 wine samples of Moravian and foreign origin were analysed for ochratoxin A contamination. A fast analytical method based on immunoaffinity column clean-up and followed by the ultra performance liquid chromatography coupled to fluorescence detection was used. LOD and LOQ values were 0.3 and 1.0 ng/L. Ochratoxin A was detected in 11% of Moravian wines and the detected OTA level ranged from 1.2 to 71.2 ng/L. In foreign wines, OTA level ranged from 1.6 to 227.0 ng/L. The values of OTA in all studied samples were significantly below the maximum allowable limit, 2.0 μg/kg, set by the European Union.