Simultaneous determination of multi-mycotoxins in palm kernel cake (PKC) using liquid chromatography-tandem mass spectrometry (LC-MS/MS)

Palm kernel cake (PKC) is a useful source of protein and energy for livestock. Recently, it has been used as an ingredient in poultry feed. Mycotoxin contamination of PKC due to inappropriate handling during production and storage has increased public concern about economic losses and health risks for poultry and humans. This concern has accentuated the need for the evaluation of mycotoxins in PKC. Furthermore, a method for quantifying mycotoxins in PKC has so far not been established. The aims of this study were therefore (1) to develop a method for the simultaneous determination of mycotoxins in PKC and (2) to validate and verify the method. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using an electrospray ionisation interface (ESI) in both positive- and negative-ion modes was developed for the simultaneous determination of aflatoxins (AFB₁, AFB₂, AFG₁ and AFG₂), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins (FB₁ and FB₂), T-2 and HT-2 toxin in PKC. An optimum method using a 0.2 ml min^–1 flow rate, 0.2% formic acid in aqueous phase, 10% organic phase at the beginning and 90% organic phase at the end of the gradient was achieved. The extraction of mycotoxins was performed using a solvent mixture of acetonitrile–water–formic acid (79:20:1, v/v) without further clean-up. The mean recoveries of mycotoxins in spiked PKC samples ranged from 81% to 112%. Limits of detection (LODs) and limits of quantification (LOQs) for mycotoxin standards and PKC samples ranged from 0.02 to 17.5 μg kg^?1 and from 0.06 to 58.0 μg kg^?1, respectively. Finally, the newly developed method was successfully applied to PKC samples. The results illustrated the fact that the method is efficient and accurate for the simultaneous multi-mycotoxin determination in PKC, which can be ideal for routine analysis.     

高效液相色谱-串联质谱法同时测定调味品中8种人工合成甜味剂

目的 建立一种高效液相色谱-串联质谱法(HPLC-MS/MS)同时测定调味品中8种人工合成甜味剂(安赛蜜、甜蜜素、糖精、阿斯巴甜、阿力甜、纽甜、三氯蔗糖、新橘皮苷二氢查耳酮).方法 样品用水提取,提取液用甲醇沉淀水溶性大分子化合物,离心后取上清液经过中性氧化铝固相萃取柱分离色素,采用C18色谱分离柱,以10 mmol/L甲酸铵溶液-乙腈进行梯度洗脱,电喷雾负离子模式下多反应监测(MRM)模式检测.结果 线性范围分别为糖精于0.05～5μg/ml,三氯蔗糖于0.1～ 10 μg/ml,其它甜味剂于0.01～1μg/ml,线性关系良好,r2＞0.990.在3个添加水平下,样品平均回收率为82.7％～117.9％,RSD为0.6％～10.6％.甜味剂于液体及半固体基质中的检出限均为0.01 ～0.1 mg/kg,于固体基质中的检出限为0.1～1 mg/kg.结论 本方法选择性强、灵敏度高、处理方法简单,可用于调味品中8种人工合成甜味剂的测定.     

HPLC-MS/MS同时检测大鼠体内三聚氰胺和三聚氰酸含量

目的建立HPLC-MS/MS同时检测大鼠血浆和组织中三聚氰胺和三聚氰酸含量的方法。方法以同位素标记的三聚氰胺和三聚氰酸作为内标物,大鼠血浆和组织经二氯甲烷-乙腈前处理后,经色谱柱分离,串联离子阱质谱采用ESI源按运行时间段切换正、负离子模式进行测定。结果在0.3～75μg/ml范围内,三聚氰酸和三聚氰胺具有良好的线性(r≥0.998)。在0.9、5.0、50μg/ml的给药大鼠的血浆样本中,三聚氰酸和三聚氰胺的回收率分别为97.4%～99.4%、96.8%～98.9%,两者的变异系数为2.43%～6.35%(日内)、1.70%～4.12%(日间)和0.30%～9.17%(日内)、0.75%～3.39%(日间);在0.9、5.0、50μg/ml的给药大鼠肝组织样本中,三聚氰酸和三聚氰胺的回收率分别为90.8%～104.6%、91.7%～106.0%,对应的变异系数为3.70%～5.14%(日内)、2.84%～4.50%(日间)和1.31%～2.21%(日内)、1.12%～3.36%(日间)。结论该方法样品前处理简单,基质干扰小,分析效率高,具有良好的精密度、准确度和特异性,是进行三聚氰酸、三聚氰胺在动物体内的组织代谢和毒性研究的理想分析方法。     

粮谷中三环唑残留量的液相色谱-质谱/质谱检测

本文建立了玉米、大麦、糙米、大米、小麦五种粮谷基质中三环唑残留量的液相色谱-质谱／质谱检测方法。样品经丙酮涡旋振荡提取,再经中性氧化铝固相萃取柱净化后,由液相色谱-质谱／质谱检测,外标法定量。方法的定量限为0.01 mg/kg,标准品浓度在2.5 ng/mL~80 ng/mL呈良好的线性关系,相关系数大于0.99。 粮谷样品在0.01、0.02和3.00 mg／kg添加水平的回收率范围分别为72.1%~95.6%,73.0%~95.4%,80.1%~99.2%,相对标准偏差范围在2.2%~7.4%。本方法方便、快速、溶剂消耗低、灵敏度高、回收率稳定,可以满足进出口粮谷中三环唑残留量的检测需求。     

QuEChERS结合高效液相色谱-串联质谱法测定粮谷中16种真菌毒素

建立了QuEChERS结合高效液相色谱-串联质谱仪(HPLC-MS/MS)同时测定粮谷中16种真菌毒素残留量的方法,样品经乙腈-水-乙酸(84∶15∶1,v/v)溶液超声提取,提取液采用C18、MgSO4净化,净化液过0.22μm微孔滤膜,用HPLC-MS/MS分析检测。Acquity UPLC BEH C18柱为分析柱,甲醇/乙腈(4+6)-0.1%甲酸水溶液为流动相进行梯度洗脱,采用电喷雾正负离子(ESI+、ESI-)模式同时电离,多反应监测(MRM)模式检测,外标法定量。结果表明,16种真菌在相应的浓度范围内线性关系良好(相关系数r2>0.995),方法定量限为0.3~3.5μg/kg,在低、中、高3个不同浓度的添加水平下,平均回收率为90.6%~106.5%,相对标准偏差≤8.8%(n=6),满足日常检测要求。该方法前处理简单,测定快速、准确,灵敏度高,适用于粮谷中16种真菌毒素残留的定性和定量分析。     

气相色谱-串联质谱法同时测定肉制品中氯霉素、甲砜霉素残留

建立了肉制品中氯霉素、甲砜霉素的气相色谱串联质谱检测方法。样品经均质后,用乙酸乙酯提取,正己烷脱脂,弗罗里硅土小柱净化,衍生后用气相色谱串联质谱法检测,内标法定量。优化了二级质谱条件,包括离子对及碰撞电压。该方法检出限为氯霉素(CAP)0.02μg/kg,甲砜霉素(TAP)0.1μg/kg,加标回收率均在86%~97%之间,相对标准偏差(RSD)在3.8%~12.3%之间,在0.1~20 ng/mL范围内都呈现出良好线性关系。     

Simultaneous determination of water-soluble vitamins in beverages and dietary supplements by LC-MS/MS

An LC-MS/MS method was developed for the simultaneous determination of 15 water-soluble vitamins that are widely used as additives in beverages and dietary supplements. This combined method involves the following simple pre-treatment procedures: dietary supplement samples were prepared by centrifugation and filtration after an extraction step, whereas beverage samples were diluted prior to injection. Chromatographic analysis in this method utilised a multi-mode ODS column, which provided reverse-phase, anion- and cation-exchange capacities, and therefore improved the retention of highly polar analytes such as water-soluble vitamins. Additionally, the multi-mode ODS column did not require adding ion pair reagents to the mobile phase. We optimised the chromatographic separation of 15 water-soluble vitamins by adjusting the mobile phase pH and the organic solvent. We also conducted an analysis of a NIST Standard Reference Material (SRM 3280 Multi-vitamin/Multi-element tablets) using this method to verify its accuracy. In addition, the method was applied to identify the vitamins in commercial beverages and dietary supplements. By comparing results with the label values and results obtained by official methods, it was concluded that the method could be used for quality control and to compose nutrition labels for vitamin-enriched products.     

QuEChERS-LC-MS/MS联用技术对浆果中多种农药残留的测定

为建立检测浆果中多种农残的方法,运用QuEChERS前处理技术,结合高效液相色谱与串联质谱联用（HPLC-MS/MS）技术同时测定浆果中10种农药残留。结果显示,最优分散剂组合为10 g样品中加入PSA 50 mg,GCB 2.5 mg和C18 50 mg进行基质的净化,此条件下平均回收率达到75.38%。10种农药对照品在1～100 μg/L范围内,呈现良好的线性关系,测定蓝莓中10种农药残留的加标回收率为95.31%～111.26%,相对标准偏差为0.90%～4.16%,测定葡萄中10种农药残留的加标回收率为90.37%～116.20%,相对标准偏差为0.80%～5.09%。该方法简便、快速、准确,适用于常见浆果中农药残留的分析。     

HPLC-MS/MS测定猪肉和猪肝中氯霉素残留量的研究

建立高效液相色谱-串联质谱法(HPLC-MS/MS)检测猪肉和猪肝中氯霉素药物残留的分析方法。样品经4%的氯化钠溶液和乙腈提取并沉淀蛋白质,正己烷脱脂净化,乙酸乙酯液液萃取,再浓缩定容,上HPLC-MS/MS仪器,用Syncronis C18柱分离,以乙腈-水(40∶60)作为流动相,采用电喷雾离子源(ESI),负离子模式,多反应监测(MRM)方式检测,用氯霉素-D5作内标物来定量。在该试验条件下,氯霉素在1～15ng/mL浓度呈良好的线性关系,r=0.999 2,最低检出浓度为0.1μg/kg,样品的加样回收率在90.0%～110.0%,重复性好RSD<3.0%。该方法能对猪肉和猪肝中氯霉素残留进行定性及定量分析,方法精密度较好、准确度较高、选择性好,结果满意。     

高效液相色谱-串联质谱法测定陈皮中7种新烟碱类农药残留

目的 建立高效液相色谱串联质谱（HPLC-MS/MS）分析方法测定陈皮中噻虫嗪、氯噻啉、吡虫啉、啶虫脒、噻虫胺、噻虫啉 、呋虫胺7 种新烟碱类农药的残留。方法 陈皮中的7 种新烟碱类农药经乙腈提取,QuEChERS方法净化后,液相色谱串联质谱（HPLC-MS/MS）分离和测定,外标法定量。结果 方法检低限为 0.1~2 μg·kg-1,在方法的检测限与500 μg·kg-1测定范围内有良好的线性关系（R＞0.9995 ）,在所添加3个水平浓度下,方法的回收率在82.7%~106.1%,相对标准偏差在1.8~11.2%。结论 结果表明,该方法准确、简单快速,满足农药残留检测方法要求。     

蜂胶胶囊中多种硝基咪唑类药物残留的检测

本文建立了采用液相色谱-串联质谱法测定蜂胶胶囊(以蜂胶为主要原料的保健食品)中多种硝基咪唑类药物(甲硝唑、洛硝哒唑、异丙硝唑、二甲硝基咪唑、羟基甲硝唑、羟甲基甲硝咪唑)残留的检测方法。样品经0.1 mol/L盐酸溶液溶解分散,涡旋混匀,超声提取目标成分,通过HLB SPE小柱净化;采用Waters ACQUITY UPLC?BEH C18(1.7μm,2.1 m×100 mm)色谱柱进行分离,流动相为0.1%甲酸水溶液-乙腈,梯度洗脱,经三重四级杆串联质谱测定,电喷雾正离子MRM模式检测,离子丰度比定性,外标法定量。结果6种目标分析物线性关系良好,相关系数均大于0.998;在2.5、5.0、10.0μg/kg三个水平下,回收率为68.12%～92.20%,RSD为1.20%～5.83%;该方法简单可靠,重复性好,推广应用前景较好,能适用于蜂胶保健食品中多种痕量硝基咪唑类药物的同时检测。     

Simultaneous determination of residues of trichlorfon and dichlorvos in animal tissues by LC-MS/MS

Trichlorfon is a thermally unstable insecticide that can be easily decomposed to dichlorvos at high temperatures. In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of the residues of trichlorfon and dichlorvos in animal tissues. Trichlorfon and dichlorvos in animal tissues were extracted with dichloromethane, homogenized/shaken, concentrated, and determined by LC-MS/MS. The two insecticides can be effectively separated and individually determined. The limits of detection (LODs) of trichlorfon and dichlorvos were 0.04 and 0.07 µg kg^?1, respectively; the limits of quantification (LOQs) of the two insecticides were both 5 µg kg^?1. The average recoveries for three spiked blank samples at 10, 20 and 40 µg kg^?1 were in the range 85–106%, with relative standard deviations (RSDs) below 10.6%, which falls in a reasonable range for the analysis of the two insecticides in animal-derived foods. The method is fit-for-purpose for the simultaneous determination of residues of trichlorfon and dichlorvos in animal tissues.     

Quantitative determination of mycotoxins in urine by LC-MS/MS

Naturally occurring mycotoxins are responsible for a wide array of adverse health effects. The measurement of urinary mycotoxin levels is a useful means of assessing an individual's exposure, but the development of sensitive and accurate analytical methods for detecting mycotoxins and their metabolites in urine samples is challenging. Urinary mycotoxins are present in low pg ml^–1 concentrations, and the chromatographic identification of their metabolites can be obscured by other endogenous metabolites. We developed an analytical method focused on the selection of two appropriate multiple-reaction monitoring transition for unambiguous identification and quantification of carcinogenic aflatoxin M₁ (AFM₁), ochratoxin A (OTA) and fumonisin B₁, B₂ (FB₁, FB₂) in urine samples from a small volunteer group in a pilot study. AFM₁, OTA, FB₁ and FB₂ were concentrated selectively, interfering substances were removed using an immunoaffinity column (IAC), and mycotoxins were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in combination with a stable-isotope standard-dilution assay (SIDA). The method was sensitive enough to measure mycotoxins and their metabolites at pg ml^–1 levels in urine. The combination of LC-MS/MS and SIDA was critical to distinguishing pseudo-OTα interference from genuine OTα. Twelve urine samples contained OTA ranging from 0.013 to 0.093 ng ml^?1 (mean = 0.031 ng ml^?1). AFM₁ were detected in one sample at a 0.002 ng ml^?1 level, while FB₁ and FB₂ were undetectable in all 12 samples. None of the samples in this pilot study contained a detectable level of OTα, despite the presence of OTA, and this may suggest the need for further epidemiological investigation of OTA exposure in the Korean population.     

液相色谱-电喷雾串联质谱法测定饮用水中的萘二酚类物质

建立了饮用水中七种萘二酚的液相色谱-电喷雾串联质谱分析方法。样品用C18固相萃取柱富集,经滤膜过滤后进样,以甲醇-水为流动相,梯度洗脱,经C18柱分离后,采用多反应监测(MRM)负离子模式检测,外标法定量。空白样品及其添加实验结果表明,特征离子相对强度的比值稳定,无基质干扰,结合保留时间可实现准确的定性定量。在优化实验条件下,萘二酚类物质线性范围为0.50~50μg/L,线性关系良好,相关系数均大于0.998。方法检出限(以信噪比为3计)为1.0~3.0 ng/L,方法定量限(以信噪比为10计)为4.0~10 ng/L,井水、自来水、矿泉水样品添加水平为4.0~50 ng/L时,回收率为81.4%~112%,相对标准偏差(n=6)为2.1%~7.8%。该方法有前处理简单、回收率高、精密度好,灵敏度高,选择性强的优点,适用于饮用水中萘二酚类物质的测定。     

高效液相色谱-质谱联用法测定酱油中三氯蔗糖的不确定度评估

采用高效液相色谱-质谱联用法测定酱油中三氯蔗糖的含量,建立了不确定度评定模型。系统分析并计算测量全过程中的不确定度各分量,通过比较各分量的大小,得出影响三氯蔗糖结果的不确定度来源主要是重复性测定和标准溶液的配制。最终计算得到三氯蔗糖的总合成标准不确定度为0.339 mg/kg,扩展不确定度为0.677 mg/kg,测量结果不确定度表示为[（13.38±0.677） mg/kg,k=2]。     

超声辅助萃取-液相色谱-串联质谱法同时检测水产品中11种有机磷酸酯类阻燃剂

目的:建立了超声辅助萃取技术结合高效液相色谱-串联质谱联用技术同时提取和测定水产品中11种有机磷酸酯类阻燃剂的分析方法。方法:采用超声辅助技术对样品进行萃取,高效液相色谱-串联质谱联用技术分离检测,正离子多反应监测(MRM)模式定量分析。考察了萃取溶剂、萃取体积、萃取时间和不同流动相对实验结果的影响。结果:二氯甲烷为萃取溶剂,萃取体积为 10 mL,萃取时间为 10 min,0.1%甲酸甲醇-0.1%甲酸水为流动相,以梯度洗脱的方式分离为最优条件。在该条件下,11种有机磷酸酯类阻燃剂分离良好,相关系数大于0.998。加标回收率为91.2%~110.5%,相对标准偏差为0.14%~6.6%。方法定量限为0.020~5.71 μg·kg^-1。结论:该方法前处理简单、快速、萃取效率高,能够应用于水产品中11种有机磷酸酯类阻燃剂的分析检测。     

HPLC-MS/MS检测卷烟主、侧流烟气中的杂环胺

建立了MCX阳离子柱固相萃取净化、大气压电离模式下液相色谱串联四极杆质谱测定8种杂环胺类的方法,并采用该方法测定了8种卷烟样品主、侧流烟气中这8种杂环胺的含量。结果表明:①方法的检测限为0.042～2.8ng/支,回收率为68%～108%,RSD为1.6%～8.8%;②这些卷烟样品主、侧流烟气中均检测到MeAαC,AαC,Trp-p-1,Trp-p-2;③卷烟主、侧流烟气中的AαC,MeAαC,Trp-p-2和Trp-p-1释放量之间均相关;AαC与MeAαC,Trp-p-2与Trp-p-1的相关性显著;④除1种卷烟样品外,其余卷烟样品侧流烟气中杂环胺的释放量都高于主流烟气。     

Simultaneous determination of nine acaricides and two metabolites in comb honey by LC/MS/MS

ABSTRACT

We developed a method for the simultaneous determination of acaricides in comb honey using LC/MS/MS. Because methods for honey analysis had not previously been applied to comb honey, we modified three techniques for sample preparation and LC/MS/MS conditions. First, we used a modified QuEChERS method that changed the extraction solution from ethyl acetate to acetonitrile. Second, we replaced the InertSep® MA-1 (30 mg, 1 ml) clean-up cartridge with an Oasis® HLB (60 mg, 3 ml). Third, we changed the ionisation mode from ESI to atmospheric pressure chemical ionisation (APCI). With these modifications, sample matrices had no effect on the identification and quantification of analytes, using an external solvent calibration curve. We verified this new method with nine acaricides and two metabolites on comb honey and honey samples from three different honey origins. The trueness ranged from 74.0 to 99.4%. The relative standard deviation of repeatability (RSD_r) ranged from 0.8 to 14.8% and that of within-laboratory reproducibility (RSD_WR) ranged from 1.3 to 14.8%. All criteria met Japanese validation guidelines. The LOQ was 1.0 μg kg^–1 for all analytes. We applied this method to 10 comb honey and 31 honey samples commercially available in Tokyo. From the results of the analysis of 41 samples, we observed that amitraz remained as N-(2,4-dimethylphenyl)-N-methylformamidine (DMPF) in 9 comb honey and 23 honey samples and that their residual concentrations were less than 20 μg kg^–1. Using this new method, we improved recovery and precision, which enabled precise quantitative determination. Furthermore, the residual amitraz value in honey determined by both this new and the previous method were in good agreement.     

Determination of chloramphenicol and zeranols in pig muscle by immunoaffinity column clean-up and LC-MS/MS analysis

An immunoaffinity column clean-up and LC-MS/MS method was successfully developed for simultaneous determination of chloramphenicol, zearalanone, α-zearalanol, β-zearalanol, zearalenone, α-zearalenol and β-zearalenol in pig muscle. The sample was extracted with diethyl ether after enzymatic digestion by β-glucuronidase/sulfatase. The extracted solution was evaporated to dryness and the residue was then dissolved in 1 ml of 50% acetonitrile solution. After filtration and dilution with phosphate buffer solution (PBS), the reconstituted solution was cleaned-up with an IAC-CZ immunoaffinity column and then analysed by HPLC-MS/MS. The established method were validated by linearity (r ≥ 0.9990), precision (RSD ≥ 2.9%), average recovery (74.5–105.0%) and limit of detection (0.04–0.10 μg kg^–1). The developed method is rapid, reliable, sensitive, accurate and has good applicability for real samples.     

葵花籽中脂肪酸的气相色谱-质谱分析

对葵花籽中脂肪酸的组成和含量进行测定。采用索氏提取法提取其脂肪酸,再进行甲酯化处理,以气相色谱-质谱联用仪进行了分离和鉴定。由葵花籽中分离鉴定出4种脂肪酸,脂肪酸的主要组成是不饱和脂肪酸。