QuEChERS-超高效液相色谱串联质谱法测定土壤中三硝基酚类物质

建立了超高效液相色谱串联质谱(UPLC-MS/MS)同时测定3种三硝基酚类残留量的方法。样品经改进的QuEChERS(快速、简单、廉价、高效、灵活和安全)前处理方法一步完成提取净化,经添加1%甲酸的乙腈提取,C18和石墨化炭黑(GCB)吸附剂填料净化,提取液经离心后直接过膜上机检测,提取和净化的效果能够满足检测要求。UPLC-MS/MS方法采用Accucore PFP色谱柱(150 mm×2.1 mm,2.6μm),柱温30℃,流动相为乙腈和乙酸铵缓冲盐,梯度洗脱,流速0.3 mL/min,电喷雾电离源负离子模式(ESI-)、多反应监测(MRM)模式检测,外标法定量。2,4,6-三硝基苯酚、2,4,6-三硝基间苯二酚和2,4,6-三硝基均苯三酚3种三硝基酚类物质在0.005~5.0 mg/L范围内线性关系良好,相关系数为0.9942~0.9962。在0.01,0.1和1.0 mg/kg水平下的平均加标回收率为79.3%~94.8%;相对标准偏差为3.1%~6.6%;方法的检出限(S/N=3)为0.002~0.005 mg/kg。本方法简单、快速、灵敏、准确,满足环境污染检测的要求。     

固相萃取/超高效液相色谱-串联质谱测定水果中5种植物生长调节剂残留量

建立了固相萃取/超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定水果中6-苄基腺嘌呤(6-BA)、噻苯隆、氯吡脲、多效唑和烯效唑5种植物生长调节剂残留量的分析方法。水果样品经乙腈提取,NH2固相萃取小柱进行富集、净化,以二氯甲烷-甲醇(92∶8)为洗脱溶液,浓缩定容后,用Waters ACQUITY UPLC BEH C18(50 mm×2.1 mm,1.7μm)色谱柱分离,流速0.3 m L/min,以水-甲醇为流动相梯度洗脱,于UPLC-MS/MS仪多反应监测(MRM)模式测定,基质匹配标准溶液外标法定量。结果表明,5种植物生长调节剂在5~500 ng/m L浓度范围内呈良好的线性关系,相关系数(r2)为0.996 1~0.999 6。在0.004,0.02,0.1 mg/kg加标水平下,方法的回收率为75.6%~110.5%,相对标准偏差(RSD)为1.2%~12.8%,方法检出限(LOD,S/N≥3)为0.001~0.002 mg/kg,定量下限(LOQ,S/N≥10)为0.003~0.006 mg/kg。该方法操作简便、灵敏度高、准确可靠,适用于水果中5种植物生长调节剂残留量的同时测定。     

UPLC-MS/MS法同时测定土壤中3种磺酰脲类除草剂残留

建立了QuEChERS法–超高效液相色谱–串联质谱法(UPLC-MS/MS)快速测定土壤中噻吩磺隆、苯磺隆、氯嘧磺隆3种磺酰脲类除草剂的方法。采用振荡提取、QuEChERS法净化方法处理土壤样品,利用UPLC-MS/MS分析,在多反应监测(MRM)模式下以0.1%甲酸水和乙腈为流动相梯度洗脱。3种除草剂在0.5~500μg/L的质量浓度范围内线性关系良好,相关系数为:0.996~0.999。在10,50μg/kg水平下进行加标回收实验,平均回收率为81.4%~92.9%,RSD为5.5%~10.6%,方法检出限(S/N=3)为0.12~0.16μg/kg。方法可用于大量实际土壤样品中3种除草剂的检测。     

复合分子印迹固相萃取-HPLC-MS/MS法测定植物源性食品中多种农药残留

建立了复合分子印迹固相萃取(CMISPE)-高效液相色谱-三重四级杆串联质谱(HPLC-MS/MS)同时检测多种植物源性食品中20种三嗪类和磺酰脲类除草剂残留的分析方法。样品经乙腈提取后,利用液液萃取及复合分子印迹固相萃取小柱净化。液相色谱以乙腈和1%甲酸溶液作为流动相梯度洗脱,C8色谱柱分离,在多反应监测(MRM)正离子电喷雾扫描模式下进行HPLC-MS/MS分析。结果表明:20种除草剂在0.5~20 ng/m L范围内线性关系良好,相关系数均在0.99以上。对玉米样品进行3个水平的加标回收试验(5,10,20μg/kg),20种目标化合物的回收率在62.7%~117.4%之间,相对标准偏差(n=6)为1.7%~13.9%。检出限(S/N≥3)均小于0.63μg/kg,定量限(S/N≥10)均小于2.1μg/kg。方法适用于植物源性食品中20种三嗪类及磺酰脲类农药残留的检测。     

高效液相色谱-串联质谱法同时测定农田土壤中31种三嗪类除草剂残留

建立了高效液相色谱-三重四极杆串联质谱(HPLC-MS/MS)同时检测农田土壤中31种三嗪类除草剂残留的分析方法。土壤样本经加速溶剂萃取,Oasis MCX固相萃取柱净化后,在多反应监测(MRM)正离子电喷雾模式下进行HPLC-MS/MS分析。色谱柱为Phenomenex Luna C18反相柱(150 mm×2.0 mm×3μm),流动相为梯度变化的乙腈和0.1%甲酸溶液。检出限(S/N≥3)为0.008~0.440μg/L,在各自的考察浓度范围内线性关系良好(r≥0.996);在0.40~40.0μg/kg添加水平内,平均加标回收率为76.9%~102.0%,RSD为3.4%~10.3%。利用本方法对沈阳地区农田表土的筛查发现,阿特拉津、西玛津、扑草净和脱乙基阿特拉津为该区域主要的三嗪类除草剂物种。     

NANO碳净化-超高效液相色谱-串联质谱法测定东北黑土壤中多农残含量

本文使用NANO碳净化柱对土壤中的31种农药进行净化,并且通过超高效液相色谱-串联质谱法(UPLC-MS/MS)进行测定。土壤样品经过NANO碳净化柱,净化效果良好。31种农药的检出限为0.001~0.01mg/kg,定量限为0.003~0.033mg/kg,添加回收率在70%~120%之间,相对标准偏差(RSD)在0%~10%之间。结果表明,该方法简单、快捷、灵敏度高,线性范围、回收率和精密度均适合土壤中的31种农药残留检测,在土壤农药残留筛查中具有较好的应用前景。     

超高效液相色谱-串联质谱法测定湿疹膏中67种激素EI北大核心CSCD

建立了湿疹膏中67种激素的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。样品先经饱和NaCl溶液分散,再经乙酸乙酯提取,QuEChERS净化后,UPLC-MS/MS检测,选择Waters AcQuityBEH C18色谱柱(1.7μm, 2.1 mm×100 mm),多反应监测模式扫描。67种激素在相应的浓度范围内,线性关系良好,相关系数均大于0.995,在3个不同浓度加标水平下,平均回收率为71.8%~115.9%,相对标准偏差(RSD)为1.7%~12.5%,定量限(LOQ)范围为0.15~1.00μg/kg,该方法能够满足湿疹膏中67种激素的检测需求。     

高效液相色谱/质谱法测定土壤中10种磺酰脲类除草剂多残留

建立了高效液相色谱/质谱法(HPLC-MS)同时检测土壤中10种磺酰脲类除草剂多残留量的方法。样品在磷酸缓冲液(pH值7.8):甲醇(8∶2,V/V)中经超声波萃取,提取液直接经固相萃取小柱净化,采用HPLC-ESI( )-MS进行定性定量分析。比较了C leanert C18,C leannertHXN和Oasis HLB 3种SPE商品柱的净化效果,结果表明C leanert C18和C leannertHXN柱的净化效果和回收率均较好。10种磺酰脲类农药的液相色谱分离在乙腈-甲醇-水(0.2%冰醋酸)梯度洗脱下完成,10个化合物的保留时间在10~16 m in。10种磺酰脲类除草剂在0.1~10.0 mg/L范围内线性良好,相关系数均在0.9964~0.9989之间;相对标准偏差在0.99%~4.26%之间。在0.01~1.0 mg/kg添加水平范围内,平均添加回收率在80.2%~104.5%之间(除苯磺隆)。本方法中10种磺酰脲类除草剂在土壤中的检出限为0.6~3.5μg/kg之间。     

QuEChERS结合柱净化的超高效液相色谱-串联质谱法测定有机肥中46种抗生素

建立了超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定有机肥中磺胺类、喹诺酮类、大环内酯类46种抗生素的分析方法。样品用乙腈-EDTA缓冲溶液(p H 10.0)提取,盐析后离心分层,乙腈层按Qu ECh ERS法,采用吸附剂净化;缓冲溶液层经HLB柱净化。ACQUITY UPLC BEH C18柱用作色谱分离,以2mmol/L甲酸铵水溶液(含0.1%甲酸)-甲醇为流动相进行梯度洗脱;电喷雾电离源正离子(ESI+)多反应监测(MRM)模式检测,基质外标法定量。46种抗生素在1~200μg/L范围内线性关系良好,相关系数(r2)为0.996 6~0.999 9。在25,100,400μg/kg加标浓度下,3类抗生素的回收率分别为67.8%~95.6%,65.6%~89.4%和66.6%~107.8%,相对标准偏差为0.4%~11.9%;方法检出限(S/N=3)为0.6~4.6μg/kg,定量下限(S/N=10)为2.1~15.4μg/kg。     

QuEChERS-超高效液相色谱-串联质谱法测定坚果中38种农药残留

建立了检测4种坚果(花生、杏仁、腰果、核桃)中38种农药残留的QuEChERS-超高效液相色谱-串联质谱(UPLC-MS/MS)方法.样品均质后,用乙腈进行提取,经PSA和C18净化后,采用Oasis PRiME HLB固相萃取柱进一步净化, UPLC-MS/MS分析.对样品前处理和色谱方法进行了优化.在多重反应监测(MRM)模式下进行质谱分析,外标法定量.38种农药的检出限范围(S/N=3)为0.01~10 μg/kg,定量限(S/N=10)为0.05~20 μg/kg,线性关系良好(r>0.991).4种坚果中农药的平均加标回收率为51.0%~126.0%,相对标准偏差均小于20%.此方法灵敏、准确、有效,可用于坚果类食品中多种农药残留的同时测定.     

Large-scale pesticide testing in olives by liquid chromatography–electrospray tandem mass spectrometry using two sample preparation methods based on matrix solid-phase dispersion and QuEChERS

In this work we have evaluated the performance of two sample preparation methodologies for the large-scale multiresidue analysis of pesticides in olives using liquid chromatography–electrospray tandem mass spectrometry (LC–MS/MS). The tested sample treatment methodologies were: (1) liquid–liquid partitioning with acetonitrile followed by dispersive solid-phase extraction clean-up using GCB, PSA and C₁₈ sorbents (QuEChERS method – modified for fatty vegetables) and (2) matrix solid-phase dispersion (MSPD) using aminopropyl as sorbent material and a final clean-up performed in the elution step using Florisil. An LC–MS/MS method covering 104 multiclass pesticides was developed to examine the performance of these two protocols. The separation of the compounds from the olive extracts was achieved using a short C₁₈ column (50 mm × 4.6 mm i.d.) with 1.8 μm particle size. The identification and confirmation of the compounds was based on retention time matching along with the presence (and ratio) of two typical MRM transitions. Limits of detection obtained were lower than 10 μg kg⁻¹ for 89% analytes using both sample treatment protocols. Recoveries studies performed on olives samples spiked at two concentration levels (10 and 100 μg kg⁻¹) yielded average recoveries in the range 70–120% for most analytes when QuEChERS procedure is employed. When MSPD was the choice for sample extraction, recoveries obtained were in the range 50–70% for most of target compounds. The proposed methods were successfully applied to the analysis of real olives samples, revealing the presence of some of the target species in the μg kg⁻¹ range. Besides the evaluation of the sample preparation approaches, we also discuss the use of advanced software features associated to MRM method development that overcome several limitations and drawbacks associated to MS/MS methods (time segments boundaries, tedious method development/manual scheduling and acquisition limitations). This software feature recently offered by different vendors is based on an algorithm that associates retention time data for each individual MS/MS transition, so that the number of simultaneously traced transitions throughout the entire chromatographic run (dwell times and sensitivity) is maximized.     

Targeted analysis of multiple pharmaceuticals,plant toxins and other secondary metabolites in herbal dietary supplements by ultra-high performance liquid chromatography–quadrupole-orbital ion trap mass spectrometry

In this study, an ultra-high performance liquid chromatography–quadrupole-orbital ion trap mass spectrometry (UHPLC–Q-orbitrap MS) method was developed and validated for simultaneous determination of 96 pharmaceuticals, plant toxins, and other plant secondary metabolites in herbal dietary supplements. Target analytes were extracted from samples using the QuEChERS (quick easy cheap effective rugged safe) procedure. The instrument was operated in full MS–data dependent tandem mass spectrometry (full MS–dd-MS/MS) acquisition mode which enabled collection of quantitative high resolution (HR) full mass spectral data and confirmatory HR MS/MS data in a single run. The method provided excellent selectivity in both full MS and dd-MS/MS mode. Under optimized collision energy settings, product ion spectra containing both precursor and two or more product ions were obtained for most of the analytes. Limits of detection (LODs) and limits of quantification (LOQs) for the method differed significantly for the examined matrices. LODs ≤ 10 μg kg⁻¹ and LOQs ≤ 50 μg kg⁻¹ were obtained for 48 to 81% of target compounds across five different matrices. With the exception of highly polar analytes, the optimized QuEChERS extraction procedure provided acceptable recoveries in the range 70%–120%. The precision of the method, characterized as the relative standard deviation (RSD, n = 5), was ≤25% and ≤18% at spiking concentrations of 50 μg kg⁻¹ and 500 μg kg⁻¹, respectively. Because of variations in matrix effects in extracts of herbal dietary supplements that differed in composition, the method of standard additions and an approach based on dilution of matrix components followed by quantification using solvent standards were applied for quantification. The procedure was used to examine commercial dietary supplements for the 96 analytes of interest. To the best of our knowledge, this is the first report of an integrated analysis and quantification of this wide range of compounds.     

Determination of N-methylcarbamate insecticides in water samples using dispersive liquid–liquid microextraction and HPLC with the aid of experimental design and desirability function

A rapid and simple method for the extraction and preconcentration of N-methylcarbamates (NMCs) (carbofuran, carbaryl and promecarb) in water samples using dispersive liquid–liquid microextraction (DLLME) using chemometrics was developed. Influence variables such as volume of extracting (CHCl₃) and dispersing solvents (ACN), pH and ionic strength, extraction time and centrifugation time and speed were screened in a 2^7–4 Plackett–Burman design was investigated. The significant variables were optimized by using a central composite design (CCD) combined with desirability function (DF). At optimum conditions values of variables set as 126 μL chloroform, 1.5 mL acetonitrile, 1 min extraction time, 10 min centrifugation at 4000 rpm min⁻¹, natural pH, 4.7% (w/v) NaCl, the separation was reached in less than 14 min using a C₁₈ column and an isocratic binary mobile phase (acetonitrile: water (50:50, v/v)) with flow rate of 1.0 mL min⁻¹. At optimum conditions method has linear response over 0.001–10 μg mL⁻¹ with detection limit between 0.0001 and 0.0005 μg mL⁻¹ with relative standard deviations (RSDs) in the range 2.18–5.06% (n = 6).     

Simple and accurate measurement of carbamazepine in surface water by use of porous membrane-protected micro-solid-phase extraction coupled with isotope dilution mass spectrometry

To achieve fast and accurate analysis of carbamazepine in surface water, we developed a novel porous membrane-protected micro-solid-phase extraction (μ-SPE) method, followed by liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) analysis. The μ-SPE device (∼0.8 × 1 cm) was fabricated by heat-sealing edges of a polypropylene membrane sheet to devise a bag enclosing the sorbent. The analytes (both carbamazepine and isotope-labelled carbamazepine) were first extracted by μ-SPE device in the sample (10 mL) via agitation, then desorbed in an organic solvent (1 mL) via ultrasonication. Several parameters such as organic solvent for pre-conditioning of μ-SPE device, amount of sorbent, adsorption time, and desorption solvent and time were investigated to optimize the μ-SPE efficiency. The optimized method has limits of detection and quantitation estimated to be 0.5 ng L⁻¹ and 1.6 ng L⁻¹, respectively. Surface water samples spiked with different amounts of carbamazepine (close to 20, 500, and 1600 ng L⁻¹, respectively) were analysed for the validation of method precision and accuracy. Good precision was obtained as demonstrated by relative standard deviations of 0.7% for the samples with concentrations of 500 and 1600 ng kg⁻¹, and 5.8% for the sample with concentration of 20 ng kg⁻¹. Good accuracy was also demonstrated by the relative recoveries in the range of 96.7%–103.5% for all samples with uncertainties of 1.1%–5.4%. Owing to the same chemical properties of carbamazepine and isotope-labelled carbamazepine, the isotope ratio in the μ-SPE procedure was accurately controlled. The use of μ-SPE coupled with IDMS analysis significantly facilitated the fast and accurate measurement of carbamazepine in surface water.     

Enantioselective determination of triazole fungicide simeconazole in vegetables, fruits, and cereals using modified QuEChERS (quick, easy, cheap, effective, rugged and safe) coupled to gas chromatography/tandem mass spectrometry

A rapid and effective method for enantioselective determination of simeconazole enantiomers in food products (cucumber, tomato, apple, pear, wheat and rice) has been developed. The enantiomers were resolved by capillary gas chromatography (GC) using a commercial chiral column (BGB-172) and a temperature program from 150 °C (held for 1 min) and then raised at 10 °C min⁻¹ to 240 °C (held for 10 min). This enantioselective gas chromatographic separation was combined with a clean-up/enrichment procedure based on the modification of QuEChERS (quick, easy, cheap, effective, rugged and safe) method. Co-extractives were removed with graphitized carbon black/primary secondary amine (GCB/PSA) solid-phase extraction (SPE) cartridges using acetonitrile:toluene (3:1, v/v) as eluent. Gas chromatography/ion trap mass spectrometry (GC–ITMS) with electron ionization (EI) was then used for qualitative and quantitative determination of the simeconazole enantiomers. Two precursor-to-product ion transitions (m/z 121–101 and 195–153) with the best signal intensity were chosen to build the multiple-reaction monitoring (MRM) acquisition method. The limits of detection for each enantiomer of simeconazole in six food products ranged between 0.4 and 0.9 μg kg⁻¹, which were much lower than maximum residue levels (MRLs) established by Japan. The methodology was successfully applied for the enantioselective analysis of simeconazole enantiomers in real samples, indicating its efficacy in investigating the environmental stereochemistry of simeconazole in food matrix.     

Application of a quick,easy, cheap,effective, rugged and safe-based method for the simultaneous extraction of chlorophenols,alkylphenols, nitrophenols and cresols in agricultural soils,analyzed by using gas chromatography–triple quadrupole-mass spectrometry/mass spectrometry

Due to the different physico-chemical properties of phenols, the development of a methodology for the simultaneous extraction and determination of phenolic compounds belonging to several families, such as chlorophenols (CPs), alkylphenols (APs), nitrophenols (NTPs) and cresols is difficult. This study shows the development and validation of a method for the analysis of 13 phenolic compounds (including CPs, APs, NTPs and cresols) in agricultural soils. For this purpose, a quick, easy, cheap, effective, rugged and safe (QuEChERS)-based procedure was developed, validated and applied to the analysis of real samples. A derivatization step prior to the final determination by gas chromatography (GC) coupled to a triple quadrupole analyzer operating in tandem mass spectrometry (QqQ-MS/MS) was performed by using acetic acid anhydride (AAA) and pyridine (Py). The optimized procedure was validated, obtaining average extraction recoveries in the range 69–103% (10 μg kg⁻¹), 65–98% (50 μg kg⁻¹), 76–112% (100 μg kg⁻¹) and 76–112% (300 μg kg⁻¹), with precision values (expressed as relative standard deviation, RSD) ≤ 22% (except for 4-chlorophenol) involving intra-day and inter-day studies. Furthermore, 15 real soil samples were analyzed by the proposed method in order to assess its applicability. Some phenolic compounds (e.g. 2,4,6-trichlorophenol or 4-tert-octylphenol) were found in the samples at trace levels (<10 μg kg⁻¹).     

Serum/plasma methylmercury determination by isotope dilution gas chromatography-inductively coupled plasma mass spectrometry

A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with ¹⁹⁸Hg-labeled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007–2.9) μg L⁻¹ could be performed with uncertainty amplification factors <2. A limit of quantification of 0.03 μg L⁻¹ was estimated at 10 times the standard deviation of concentrations measured in preparation blanks. Within- and between-run relative standard deviations were <10% at added concentration levels of 0.14 μg L⁻¹, 0.35 μg L⁻¹ and 2.8 μg L⁻¹, with recoveries in the range 82–110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; <0.03–0.19) μg L⁻¹. This is the first time methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.     

A dual validation approach to detect anthelmintic residues in bovine liver over an extended concentration range

This paper describes a method for the detection and quantification of 38 residues of the most widely used anthelmintics (including 26 veterinary drugs belonging to the benzimidazole, macrocyclic lactone and flukicide classes) in bovine liver using two different protocols for MRL and non-MRL levels. A dual validation approach was adopted to reliably quantify anthelmintic residues over an extended concentration range (1-3000 μg kg⁻¹). Sample extraction and purification was carried out using a modified QuEChERS method. A concentration step was included when analysing in the low μg kg⁻¹ range. Rapid analysis was carried out by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), which was capable of detecting residues to <2 μg kg⁻¹. The method has been single-laboratory validated according to the 2002/657/EC guidelines and met acceptability criteria in all but a few cases. The inclusion of 19 internal standards, including 14 isotopically labelled internal standards, improved accuracy, precision, decision limit (CCα) and detection capability (CCβ).     

Validation and use of a fast sample preparation method and liquid chromatography–tandem mass spectrometry in analysis of ultra-trace levels of 98 organophosphorus pesticide and carbamate residues in a total diet study involving diversified food types

This paper reports a comprehensive sensitive multi-residue liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for detection, identification and quantitation of 73 pesticides and their related products, a total of 98 analytes, belonging to organophosphorus pesticides (OPPs) and carbamates, in foods. The proposed method makes use of a modified QuEChERS (quick, easy, cheap, effective, rigged, and safe) procedure that combines isolation of the pesticides and sample clean-up in a single step. Analysis is performed by liquid chromatography-electrospray ionization–tandem mass spectrometry operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. Two main fragment ions for each pesticide were obtained to achieve the identification according to the SANCO guidelines 10684/2009. The method was validated with various food samples, including edible oil, meat, egg, cheese, chocolate, coffee, rice, tree nuts, citric fruits, vegetables, etc. No significant matrix effect was observed for tested pesticides, therefore, matrix-matched calibration was not necessary. Calibration curves were linear and covered from 1 to 20 μg L⁻¹ for all compounds studied. The average recoveries, measured at 10 μg kg⁻¹, were in the range 70–120% for all of the compounds tested with relative standard deviations below 20%, while a value of 10 μg kg⁻¹ has been established as the method limit of quantitation (MLOQ) for all target analytes. Similar trueness and precision results were also obtained for spiking at 200 μg kg⁻¹. Expanded uncertainty values were in the range 21–27% while the HorRat ratios were below 1. The method has been successfully applied to the analysis of 700 food samples in the course of a baseline monitoring study of OPPs and carbamates.     

Application of an ultrasound-assisted surfactant-enhanced emulsification microextraction method for the analysis of diethofencarb and pyrimethanil fungicides in water and fruit juice samples

In this work, a simple, practical and environmentally friendly sample pre-treatment method, ultrasound-assisted surfactant-enhanced emulsification microextraction coupled with high performance liquid chromatography–diode array detector/electrospray ionisation mass spectrometry, was developed to determine diethofencarb and pyrimethanil residues in water and fruit juice samples. Tween 80 was used as an emulsifier and carbon tetrachloride was chosen as the extraction solvent, and no dispersive organic solvent was needed, which is typically required in common dispersive liquid–liquid microextraction methods. Several variables, such as the type and volume of extraction solvent and surfactant, extraction temperature and ultrasound extraction time were investigated and optimised. Under optimal conditions, the enrichment factors were 265 and 253 for diethofencarb and pyrimethanil, respectively. The limits of detection (LODs), calculated as three times the signal-to-noise ratio (S/N), were 0.01 μg L⁻¹ for both diethofencarb and pyrimethanil. The linearity of the method was obtained in the range of 0.05–2000 μg L⁻¹, with correlation coefficients of 0.9994–0.9998. The water (at fortified levels of 0.1 and 1.0 μg L⁻¹) and fruit juice samples (at fortified levels of 0.1 and 1.0 μg L⁻¹) were successfully analysed using the proposed method, and the relative recoveries were in the range of 88–114%, 93–111%, 86–117% and 94–101%, respectively.