固相萃取-高效液相色谱串联质谱法测定原料奶中5种环境雌激素残留量的研究

建立固相萃取-高效液相色谱串联质谱法测定原料乳中环境雌激素（雌酮、雌二醇、雌三醇、己烯雌酚、双酚A）的方法。原料乳用NH2-SPE固相萃取小柱进行富集,旋转蒸发浓缩后,采用高效液相色谱串联质谱法测定。实验结果表明:各待测物在0.01～0.5μg/mL范围内具有良好的线性关系,相关系数均大于0.9978,加标回收率为68.5%～105.6%,RSD为2.56%～7.59%,最低检出限为0.22～0.56μg/L（S/N=3）。本方法操作简便,快速灵敏,适合于牛奶中痕量环境雌激素的残留分析检测。      

番茄、辣椒、茄子中甲基毒死蜱残留量测定

采用高效液相色谱-二极管阵列检测器对番茄、辣椒和茄子中甲基毒死蜱残留量进行测定。样品用乙腈提取后,经Carb/NH2固相萃取小柱净化,用C8液相色谱柱、二极管阵列检测器,对甲基毒死蜱残留量的测定可取得满意的结果。该方法样品平均加标回收率为80.7%～92.4%,相对标准偏差为1.1%～4.6%;蔬菜中甲基毒死蜱检出下限为0.02mg/kg。     

固相萃取-高效液相色谱-质谱法检测大豆中氯嘧磺隆除草剂的残留量

实验建立了固相萃取-高效液相色谱-质谱分析检测方法,对大豆中氯嘧磺隆除草剂的残留量进行了研究。样品经甲醇-超声波提取、正己烷液-液分配、固相萃取柱净化,将处理好的样品进行液相色谱定量分析、采用液相色谱-质谱进行定性检测。实验结果表明:氯嘧磺隆在0.1～200.0mg/L范围内浓度与峰面积具有良好的线性关系,相关系数为0.9997（n=3）;在2.0～100.0μg/kg范围内,加标回收率为92.6%～95.2%;RSD为1.27%～2.64%;最低检测限为10.0μg/kg（S/N=3）。本方法具有简便、快速、准确、净化效果好等特点,适用于大豆中氯嘧磺隆除草剂的残留分析检测。      

液相色谱-串联质谱法测定水产品中β-内酰胺类抗生素的残留

建立了同时测定水产品中6种β-内酰胺类抗生素药物残留的高效液相色谱-串联质谱（HPLC-MS/MS）检测方法。样品经乙腈-水（15∶2,v∶v）混合液提取,HLB固相萃取柱净化。以乙腈-0.01mol/L醋酸铵溶液（pH4.5）作为流动相,C18色谱柱进行分离,电喷雾正离子多反应监测模式进行检测。方法检测限为0.2～2.0μg/kg,加标回收率为80.8%～92.9%,相对标准偏差为2.6%～9.1%（n=9）。该方法准确、灵敏、简便,适用于水产品中6种β-内酰胺类抗生素残留的测定。      

固相萃取-高效液相色谱-荧光检测方便面中的苯并（a）芘

采用固相萃取-高效液相色谱-荧光法（HPLC-FLD）测定方便面中苯并（a）芘的含量。根据不同的食品材质对样品提取条件进行优化,采用HiCapt-Benzo苯并（a）芘专用固相萃取柱净化,反相C18（4.6mm×250mm,5μm）色谱柱分离,外标法定量。苯并（a）芘在1.0～200μg/L浓度范围内线性关系良好,相关系数R2=0.9998。本方法的定量限（S/N≥10）在方便面调料中的调味油酱料包为0.5μg/kg,在调味粉料包、菜肉包和面饼都为0.1μg/kg;添加浓度为1.0～20μg/kg时,回收率范围为78.1%～96.7%,相对标准偏差（RSD）0.97%～6.23%（n=6）。该方法前处理简单,分析周期短,具有良好的灵敏度和精密度,适用于方便面中苯并（a）芘的测定。      

高效液相色谱法测定水产品中4-己基间苯二酚

建立了水产品中4-己基间苯二酚（4-HR）残留量测定的高效液相色谱-荧光法。样品经乙腈提取,浓缩后用流动相溶解残渣,正己烷脱脂净化,过滤后供高效液相色谱（HPLC）分析。色谱条件为:WondaSilC18柱（250mm×4.6mm,5μm）;以甲醇-水（75:25,v/v）作为流动相,流速为1.0mL/min;荧光检测器激发波长为280nm,发射波长为310nm,外标法定量。结果表明:该方法在0.05～5.0μg/mL范围内线性关系良好,相关系数R2=0.9998。样品在0.1、0.2、1.0、5.0mg/kg加标水平时,平均回收率为90.9%～108.4%,相对标准偏差（RSD）为0.8%～8.1%（n=5）。方法定量限（LOQ）为0.1mg/kg。      

自制固相萃取柱-超高效液相色谱-串联质谱法同时测定果蔬中的8 种真菌毒素

建立基于自制固相萃取柱的样品净化-超高效液相色谱-串联质谱同时测定果蔬中8 种主要真菌毒素的方法,包括链格孢毒素、展青霉素、赭曲霉毒素A及橘青霉素。样品经80%乙腈溶液提取、离心后,通过自制固相萃取柱（HLB＋MCX）排除杂质干扰,流出液经氮吹至近干后,直接用超高效液相色谱-串联质谱进行测定,基质外标法定量。在较宽的线性范围内,8 种毒素的线性相关系数（r2）均不小于0.99,定量限为1～5 μg/kg,在3 个不同添加水平下的加标回收率为76.0%～102.7%,相对标准偏差为0.8%～4.7%。该法灵敏度高,操作简单﹑快速,适用于苹果、樱桃和番茄等果蔬中痕量真菌毒素的测定。     

QuEChERS净化-UPLC-MS/MS法测定番茄中19种农药残留

采用QuEChERS净化-超高效液相色谱-串联三重四极杆质谱法（UPLC-MS/MS）测定番茄中19种农药残留。经改进的QuEChERS方法进行前处理,采用Aglient-C18色谱柱分离,以4 mmol/L甲酸水溶液和甲醇为流动相进行梯度洗脱。质谱采用电喷雾（ESI）正离子源和多反应监测（MRM）模式,外标法定量。结果表明,19种农药的质量浓度为2.0～200.0 μg/L时,线性关系良好,相关系数（R2）＞0.998,定量限为0.15～1.50 μg/kg,回收率为79.8%～103.9%,相对标准偏差（RSD）为3.2%～11.8%。说明该方法灵敏度高,适合番茄中19种农药残留检测的要求。     

固相萃取-高效液相色谱法快速测定罗汉果甜甙V的含量

建立一个快速、简单、准确的固相萃取预处理高效液相色谱法测定罗汉果甜甙V含量的方法.样品经C18固相萃取管(200mg/3mL)纯化后以高效液相色谱检测.色谱柱为NH2P-50,流动相为V(乙腈):V(水)=85:15,流速为1mL/min,检测波长为210nm.标准曲线自0.025g/L～1.000g/L呈线形关系(r2=0.9993).研究表明:固相萃取法能很好的纯化罗汉果甜甙V,回收率高达98.80%,RSD为O.52%.此法样品处理简单,溶剂消耗少,费用减少,分析结果重现性好,适于推广应用.     

液相色谱-串联质谱法测定牛奶中万古霉素和去甲万古霉素残留

建立了牛奶中2种多肽类抗生素万古霉素和去甲万古霉素残留量的液相色谱-串联质谱（LC-MS/MS）检测方法。牛奶样品用三氯乙酸水溶液提取、沉淀蛋白,经混合型阳离子固相萃取柱Oasis MCX净化后,利用LC-MS/MS进行定性和定量分析。测定时样品溶液经ZORBAX SB-C18色谱柱分离,0.1%甲酸水溶液和乙腈作为流动相进行梯度洗脱,质谱测定采用正离子模式,多反应监测（MRM）。结果表明,万古霉素和去甲万古霉素的检出限为5μg/kg,回收率为72.5%～87.2%,相对标准偏差小于10%。      

高效液相色谱-串联质谱法同时测定番茄中的番茄苷与番茄碱

利用高效液相色谱-串联质谱法,建立番茄中番茄苷和番茄碱2 种主要生物碱的同时检测方法。样品经匀浆提取后,利用C18固相萃取柱净化,以5 mmol/L乙酸铵（含0.05%甲酸）-乙腈为流动相,Agilent Proshell 120 EC-C18进行分离,三重四极杆检测器,多反应监测模式进行检测。结果表明,番茄苷在50～1 000 ng/mL范围内线性良好,相关系数为0.999 1。番茄碱在5～100 ng/mL范围内线性良好,相关系数为0.999 4。对番茄苷和番茄碱进行3 个水平的添加回收实验,结果表明添加回收率在85.6%～105%之间,相对标准偏差在1.0%～6.8%之间。所建方法简单、快速、灵敏度高、重复性好,可用于番茄中番茄苷与番茄碱的快速、定量检测。实际样品检测结果表明,番茄中番茄苷的含量明显高于番茄碱。     

HPLC and spectrophotometric determination of annatto in cheese

A rapid and simple method for the detection of E 160b (annatto) in cheese and other milk products is described. After extraction with acetone, the two main components bixin and norbixin are separated from fat and #-carotene by solid-phase extraction (SPE). Both sample preparation and determination are made without halogenated solvents. For quantification of the annatto content, high-performance liquid chromatography (HPLC) and a spectrophotometric method were used. For the spectrophotometric method, extinction values of bixin and norbixin were determined in a mix of methanol and glacial acetic acid. The spectrophotometry is sufficient for the quantitative determination of the entire content of annatto. If the colorings E 100 (curcumine) or E 160f (#-apo-8'-carotenal) are present beside annatto, then HPLC is favored. Other food colors and emulsifiers do not disturb the determination. The correlation coefficient between the different methods was R²=0.9989. The recovery rates determined by spiking cheese, processed cheese, butter, and ice cream, were between 80 and 100%.     

Protective effect of dietary tomatine against dibenzo[a,l]pyrene (DBP)-induced liver and stomach tumors in rainbow trout

The potential anti-carcinogenic effects of tomatine, a mixture of commercial tomato glycoalkaloids alpha-tomatine and dehydrotomatine (10:1), were examined in the rainbow trout chemoprevention model. Prior to the chemoprevention study, a preliminary toxicity study revealed that tomatine in the diet fed daily at doses from 100 to 2000 parts per million (ppm) for 4 weeks was not toxic to trout. For the tumor study, replicate groups of 105 trout were fed diets containing dibenzo[a,l]pyrene (DBP) alone (224 ppm), (N = 3), DBP plus tomatine at 2000 ppm (N = 2), tomatine alone (N = 2), or control diet (N = 2) for 4 weeks. The fish were then returned to control diet for 8 months and necropsied for histopathology. Dietary tomatine was found to reduce DBP-initiated liver tumor incidence from 37.0 to 19.0% and stomach tumor incidence from 46.4 to 29.4%. Tomatine also reduced stomach tumor multiplicity. The tomatine-containing diets did not induce mortality, change in fish weights, or liver weights. No adverse pathological effects in the tissues of the fish on the tomatine diets were observed. Dose-response and chemopreventive mechanisms for tomatine protection remain to be examined. This is the first report on the anticarcinogenic effects of tomatine in vivo.     

A survey of the occurrence of agaritine in U.K. cultivated mushrooms and processed mushroom products

The naturally occurring compound agaritine (beta-N-[gamma-L(+)glutamyl]-4-hydroxy-methylphenyl-hydrazine) has been determined in fresh, dried and processed mushrooms. A method was developed involving extraction of the toxin into methanol, clean-up where appropriate (for processed products) by high-performance size exclusion liquid chromatography and determination by reverse-phase HPLC with electrochemical detection. Diode array UV monitoring was used for confirmation. The method had a recovery of 90-98%, a relative standard deviation of 3-5% and a limit of detection of agaritine of 5 mg/kg on a dry-weight basis. Fresh cultivated mushrooms showed agaritine levels of 100-250 mg/kg and 80-190 mg/kg for two different commercial strains. There were slight differences in levels of agaritine between mushrooms of different sizes, and between those of the same size but harvested at different times (different breaks). Retail processed mushrooms products had low agaritine levels in the range 6-33 mg/kg, with the exception of one dried sliced mushroom product found to contain 6520 mg/kg.     

A Simple and Fast HPLC Method to Determine Lycopene in Foods

Carotenoids, among which lycopene—the principal pigment found in tomatoes—are lipophilic compounds which play a very important role in human health and nutrition. They are also recognised as strong antioxidants due to their ability to trap singlet oxygen and eliminate the peroxyl radical. The availability of reliable information on lycopene content of foods is essential both for the evaluation of diet and for epidemiological research relating the intake of lycopene. This paper describes a simple and fast HPLC/UV method for lycopene determination in a wide range of food products. All-E-lycopene together with its Z isomers were eluted isocratically using a carotenoid C30 reversed-phase column. The in-house validated HPLC method had a limit of quantification of 60 ng lycopene/g product and high precision and accuracy. The analytical method was successfully applied to several food products such as raw vegetables and fruits and also processed foods. Tomato and tomato-containing products contained the highest amounts of lycopene. While raw foods and minimally processed foods contained above 94% of all-E-lycopene, processed foods (such as soups, pasta sauces, pizza and cheese) contained from 76% to 87% of all-E-lycopene.     

高效液相色谱法检测罗非鱼中丁香酚残留量

目的建立罗非鱼中丁香酚残留量的高效液相色谱分析方法。方法样品采用乙腈为提取溶剂,经超声提取、正己烷脱脂净化2次后,通过高效液相色谱技术检测,外标法定量。结果丁香酚在0.1~10.0 mg/L范围内具有良好的线性关系,相关系数为0.99998;5.00 g样品中丁香酚残留量的检出限为0.03 mg/kg,定量限为0.10 mg/kg;3个添加水平平均回收率为80.5%~101.2%,相对标准偏差为3.38%~5.39%。结论本方法具有操作简便、快速、准确的特点,适用于罗非鱼中丁香酚残留量批量检测。     

QuEChERS-HPLC法测定植物性食品中氟吗啉的残留量

以苹果、梨、葡萄、橘子、白菜、西兰花、菠菜、胡萝卜、番茄和黄瓜共10种植物性食品为研究对象,建立了植物性食品中氟吗啉残留量的QuEChERS-HPLC检测方法。样品经0.1%冰醋酸乙腈提取,醋酸钠和无水硫酸镁盐析后,取上清液,加入伯仲胺粉分散固相萃取净化,用配有二极管阵列检测器的高效液相色谱测定,外标法定量。氟吗啉在0.1²mg/L的范围内具有较好的线性关系,氟吗啉在0.1、0.2、0.5mg/kg三个添加水平平均回收率81%～116%,RSD2.3%¹2.1%,定量限为0.05mg/kg。本方法前处理简单、快速,适用于多种植物性食品中氟吗啉残留量测定。      

Simultaneous quantitative determination of Sudan dyes using liquid chromatography–atmospheric pressure photoionization–tandem mass spectrometry

Atmospheric pressure photoionization–tandem mass spectrometry (APPI–MS/MS) method has been developed for quantitative determination of Sudan I to IV dyes. This study demonstrates the applicability of a simple isocratic normal phase HPLC method using isopropanol (0.3%) in n-hexane as the mobile phase for the separation of these dyes. A simple extraction procedure using n-hexane has been applied for the extraction of these dyes from spiked samples of chilli powder and tomato sauce. The quantitative determination of Sudan I to IV is obtained from the spiked tomato sauce and chilli powder samples by external standard method under single reaction monitoring (SRM) mode. The study includes a detailed investigation on LOD, LOQ, linearity and recovery of Sudan I to IV dyes. The LOD ranged from 5–18 μg/l and LOQ ranged from 10–24 μg/l. The present method can be a powerful analytical tool for the simultaneous quantitative determination of Sudan dyes present in food products.     

Comparison of ion-specific electrode and high performance liquid chromatography methods for the determination of iodide in milk

Two methods for the determination of I⁻ in raw and processed milk were examined. A simple ion-specific electrode (ISE) method was compared against a more complex HPLC reference technique. Accuracy and precision were evaluated both within and between the 2 methods. Both methods yielded good recoveries for Ion spiked samples, ranging from 87 to 114% for ISE and 91 to 100% for HPLC. Within-run repeatability and between-run reproducibility were superior with the HPLC method, but were still more than acceptable with the ISE technique. Overall agreement of paired results between ISE and HPLC methods was good (r² = 0.85 on raw herd milk; r² = 0.84 on processed milk). The ISE method had a significant positive bias relative to the HPLC reference method. Both methods lend themselves well to the measurement of I⁻ in raw or processed milk. Given its relatively low cost and ease of use, the ISE method is well suited as a screening method. The impressive accuracy, precision, selectivity, and limit of detection of the HPLC technique make it an ideal confirmation method.     

常用炮制方法对巴戟天中游离氨基酸成分的影响

目的:建立氨基酸柱前衍生反向色谱测定法,分析比较巴戟天不同炮制品中氨基酸的差异,为其质控体系提供依据。方法:以水为溶剂,超声法提取巴戟天中的氨基酸,以异硫氰酸苯酯（PITC）柱前衍生,检测波长254nm,Sinergi 4u fusion-RP色谱柱（Phenomenex,250mm×4.6mm,4μm）,柱温35℃,测定氨基酸的含量。结果:4～5年生巴戟天生品中含有14种游离氨基酸,酒蒸氨基酸总量较生品增加约14.8%,盐蒸和甘草制氨基酸总量基本不变,盐炒氨基酸总量减少约12.4%,酒炒氨基酸总量减少约43.9%。结论:本法操作简便、灵敏度高,结果准确、可靠。巴戟天生品酒蒸后游离氨基酸总量显著增加,盐蒸和甘草制者基本不变,盐炒和酒炒者均显著降低,提示不同炮制方法对巴戟天游离氨基酸含量影响有显著差异,其机制值得深入研究。