Simultaneous Determination of 14 β-Receptor Agonists Residues in Mutton by High Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS)

[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton.

Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry

Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines （TCs）, sulfanilamides （SAs）, and quinolones （QLs）. The method consists of solid-phase extraction （SPE） and liquid chromatography-tandem mass spectrometry （LC-MS/MS） analysis, using electrospray ionization （ESI） in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation （RSD）, was below 14.6% for all the compounds. The limits of detection （LODs） varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal ＇waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems

Determination of okadaic acid related toxins from shellfish (<i>sinonovacula constricta</i>) by high performance liquid chromatography tandem mass spectrometry

Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify and quantify DSP toxins in shellfish. This new methodology could facilitate DSP monitoring and create a means of rapidly responding to incidents threatening public health. In the last years there were different analytical methods for DSP, such as mouse bioassay and LC-FLD. With the development of instrument, Liquid chromatography-mass spectrometry was substituted for other analytical methods with its good sensitivity and selectivity and without derivatization for the determination of DSP. In this report, a high performance liquid chromatogra-phytandem mass spectrometric(HPLC-MS/MS)method was developed for the simultaneous determination of okadaic acid (OA) and dinophysistoxins(DTX1) in Sinonovacula constricta. Optimization of pretreatment experiment was carried out to maximize recoveries and the effectiveness. The analytes were determined under multi-reactions monitoring (MRM) scan type with tandem mass analyzer using negative ion electrospray ionization (-ESI) mode .Finally, the detection and identification of OA and DTX-1 were based upon their retention times (RT) and the fragmentation patterns of their mass spectra. The method of LOQ for the two poisons was 0.02 mg·kg-1.The real sample test showed that this method could be used for sensitive, fast, and accurate determination of the two diarrheic shellfish poisons in shellfish.

Determination of chlorpromazine in porcine muscle using high performance liquid chromatography-tandem mass spectrometry

A rapid and accurate high performance liquid chromatography tandem mass spectrometry（HPLS-MS） method was established for quantification of chlorpromazine in pork. The porcine samples were pretreated with acetonitrile to precipitate proteins and followed by extraction with tert--butyl methyl ether（TBME）. The separation was performed on a 5 μm Agilent XDB--C18 column with gradient elution. The mobile phase A was 0.01 mol/L ammonium formate in water and mobile phase B was acetonitrile. The flow rate was at 0.8 mL/min. Quantification was performed on a triple-quadrupole tandem mass spectrometer using the multiple selected reaction monitoring（MRM） mode. Transition of m/z ＋319.1 to 58.1 was used for the quantification of chlorpromazine. The method was validated at the concentration range of 0.4040 μg/kg to 8.080 μg/kg for chlorpromazine with correlation coefficient of 0.9999. The spiked recoveries were more than 80.0% and the limit of detection（LOD） was 0.052 μg/kg. The developed method, which offers advantages of convenience, rapid, specificity and higher sensitivity, can be used for determination of chlorpromazine hydrochloride in porcine muscles.

Detection of Endocrine Disruptors in Water around Landfills

[Objectives]This study was conducted to explore the occurrence levels of endocrine disruptors(EDCs)in rural areas around a county landfill in Tongren City.[Methods]The water around the landfill was sampled and analyzed.A solid-phase extraction and high performance liquid chromatography-tandem mass spectrometry(SPE-UPLC-MS/MS)method was established for the determination of 27 EDCs.After the HLB solid-phase extraction column was activated,a water sample,which was adjusted with phosphoric acid to a pH of 2(±0.5)and added with 500 mg of disodium EDTA,was loaded,and 5 ml of water and 20%methanol water was added for washing.Next,10 ml of elution solution was added for elution,and the collected eluate was evaporated under reduced pressure at 40℃to near dryness,and 1 ml of reconstitution solution was added to a constant volume.An ACQUITY UPLC BEH C18(100×2.1 mm,2.6μm)chromatographic column was adopted for LC separation by gradient elution with pure water solution-acetonitrile as the mobile phase.For MS detection,the MRM mode was adopted for collection,and the positive and negative ion modes were switched for simultaneous determination,and the internal standard method was used for quantification.[Results]The correlation coefficient R2 was greater than 0.99 in the linear range of each target substance.The limits of quantitation in the method were between 0.05 and 2.00 ng/L,and the recoveries ranged from 75.3%to 105.7%.[Conclusions]The method has high sensitivity,good accuracy and strong practical value.

Study on Detection of Antibiotic Contents in Water around Landfill Sites

[Objectives] An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for simultaneous determination of 26 antibiotics in the water around landfills. [Methods] After an HLB solid-phase extraction column was activated, and a water sample, which was adjusted with phosphoric acid to a pH of (2±0.5) and added with 500 mg of disodium EDTA, was loaded, and 5 ml of water and 20% methanol water was added for washing. Next, 10 ml of elution solution was added for elution, and the collected eluate was evaporated under reduced pressure at 40 ℃ to near dryness, and 1 ml of reconstitution solution was added to a constant volume. An ACQUITY UPLC BEH C18 (100 mm×2.1 mm, 2.6 μm) chromatographic column was adopted for LC separation by gradient elution with 0.1% formic acid aqueous solution-acetonitrile as the mobile phase. For MS detection, the MRM mode was adopted for collection, and the positive and negative ion modes were switched for simultaneous determination, and the internal standard method was used for quantification. [Results] The correlation coefficient R2 was greater than 0.99 in the linear range of each target substance. The limits of detection ranged from 0.15 to 3.00 ng/L, and the limits of quantitation were between 0.80 and 10.00 ng/L, and the recoveries ranged from 77.9% to 104.85%. [Conclusions] The method has high sensitivity, good accuracy and strong practical value.

高效液相色谱-串联质谱法对猪肉中四种大环内酯类药物残留量的测定

A simple and sensitive method was developed for the simultaneous determination of four macrolides in pork using high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Homogenized sample was extracted with NaH2PO4 buffer and acetonitrile solution,and defatted with n-hexane.Further cleanup was performed on a Sep-Pakt C18 solid-phase extraction cartridge.The compounds were determined by LC-MS/MS operated in positive electrospray ionization mode.The limits of detection(LODs) were 0.5 μg/kg.The average recoveries at three spiked concentration levels of 1.0,5.0,10.0 μg/kg were in the range of 70%-110%,with the intra-day RSD of less than 12.9% and inter-day RSD of less than 13.4%.

液相色谱-串联质谱法测定水环境中的十氯酮

建立了分析测定水环境中十氯酮的液相色谱-串联质谱法。水样经液液萃取、净化后，采用 Eclipse plus C18柱（100 mm×2.1 mm，3.5μm）分离，乙腈和水为流动相进行梯度洗脱，在电喷雾负离子多反应监测模式下进行检测，同位素内标法定量。结果表明：采用液相色谱-质谱联用技术，证实了十氯酮在甲醇中以半缩醛的形式存在，而在丙酮/乙腈中以偕二醇的形式存在。由于十氯酮极性较强，在净化时难以洗脱，并且不耐酸，所以不能与其他有机氯农药一起分析。十氯酮在5～100μg / L 范围有良好的线性关系，相关系数 r2=0.999，检出限及定量限分别为0.70 ng / L 和2.8 ng / L；在5、40和100 ng / L 3个浓度添加水平的平均回收率为95.1％～98.9％，相对标准偏差为3.85％～4.72％。本方法具有良好的灵敏度、回收率和重现性，适用于水环境中十氯酮的测定。

高效液相色谱/质谱法识别不同明胶酶解产物中特征多肽

在不同动物胶原蛋白序列比对基础上,利用高效液相色谱/质谱联用技术(HPLC/MS)建立一种通过特征多肽进行明胶鉴别的方法。实验以牛明胶和猪明胶为对象,序列比对结果表明,牛和猪的Ⅰ型胶原蛋白α1链和α2链均存在氨基酸序列差异。利用胰蛋白酶将牛明胶和猪明胶降解,通过HPLC/MS分析了两种明胶酶解产物中的多肽片段。结果表明:牛明胶和猪明胶酶解产物中均可检测出存在序列差异的特征性多肽,其氨基酸序列差异与两种胶原蛋白序列比对结果中的序列差异一致;酶解产物中特征多肽上的脯氨酸存在不同程度的羟基化修饰,特征多肽的相对含量主要受明胶分子量范围影响。利用HPLC/MS检测明胶酶解产物中的特征多肽是一种鉴别牛明胶和猪明胶的有效方法。

超高效液相色谱-飞行时间质谱法高通量筛查乳制品中20种镇静剂

利用超高效液相色谱/高分辨飞行时间质谱,结合数据库,建立了乳制品中20种镇静剂的高通量筛查方法。样品以乙腈和酸化乙腈沉淀蛋白质和脂肪,冷冻离心浓缩,经超高效液相色谱分离,采用电喷雾离子源,正离子模式,基质匹配法进行定量分析,可在9 min内对20种镇静剂进行高通量筛查和定量分析。镇静剂的质量浓度在1～500μg/L或5～1000μg/L范围内具有较好的线性关系,检出限为0.3～1.5μg/L,定量限为1～5μg/L。在5和50μg/L添加水平时,平均回收率为76.1%～108.2%,相对标准偏差为2.5%～9.0%。利用TargetAnalysis软件建立镇静剂数据库,并应用于加标样品的筛查分析。通过数据库比对,样品中添加的镇静剂被全部筛查出来,鉴定准确度达到了100%,保留时间偏差小于0.1 min,质量偏差小于3mDa,同位素峰形匹配度大于89.5%。利用本方法对购自超市的8个不同品牌的50余份乳制品进行了筛查分析,均未检出阳性样品。

液相色谱/质谱联用法分析不同年龄鼠皮肤中I型、III型胶原蛋白相对含量

哺乳动物皮肤中真皮内的胶原蛋白含量约占70%,主要是I型、III型和少量V型胶原蛋白。利用稀酸溶解和酶法提取了大鼠皮肤中的总胶原蛋白,将胶原蛋白粗提品在60℃变性后用胰蛋白酶进行降解,液相色谱/质谱联用法分析两种胶原蛋白的特征多肽,并研究不同生长期大鼠皮肤中I型和III型胶原蛋白相对含量。结果表明,大鼠皮肤中的III型胶原蛋白的相对含量随生长期延长逐渐降低,而I型胶原蛋白的相对含量逐渐升高,8周后两种胶原蛋白的比例趋于稳定。表明使用高效液相色谱/质谱联用法分析组织中的胶原蛋白类型及其动态变化具有可行性,为更好的临床应用提供实验基础。

高效液相色谱-串联质谱法同时测定血清中游离和结合型胆汁酸

建立了高效液相色谱-串联质谱同时测定血清中游离和结合型胆汁酸的方法。血清样品经固相萃取后，在C18色谱柱上梯度洗脱，用负离子多反应监测模式检测。15种胆汁酸在0．10～100．0μmol／L的浓度范围内与响应呈良好的线性，r为0．9990～0．9999；检出限为0．001～0．006μmol／L；本方法的相对标准偏差日内不超过3．0％，日间不超过6．0％；平均回收率为86．0％～110．0％，适合于临床检测血清胆汁酸。

高效液相色谱-紫外／质谱检测法联合测定新鲜烟叶中的25种酚类物质

建立了烟叶中25种酚类物质的高效液相色谱-紫外／质谱（HPLC-UV／MS）测定方法，其中11种主要酚类物质采用HPLC—uV法进行绝对定量分析，其余采用HPLC-MS法进行半定量分析。方法验证结果表明：11种酚类标准物质在0．90—99．00mg／L（绿原酸及芸香苷为0．95～380．00mg／L）范围内呈现很好的线性关系，相关系数为0．9993～0．9999。在22．5—24．8、45．0—49．5、67．5—74．3mg／L3个水平的加标回收率为91．0％-112．4％。方法重复性的相对标准偏差（RSD）为1．48％-13．40％，日内日间精密度的RSD为0．35％-15．54％。采用本方法对云南、河南、贵州的成熟期新鲜烟叶样品进行了分析，主要酚类物质总量为贵州〉云南〉河南，贵州与河南两地间存在显著性差异；芸香苷含量为云南〉贵州〉河南，且相互间有显著性差异。本方法预处理简单，酚类物质的分析覆盖面广，可用于批量烟叶样品的检测。

HPLC-MS/MS法测定烟叶中7种植物内源激素

为获得烟草激素的质量分数数据,并分析其在抗性、生长发育等过程中的作用,采用高效液相色谱-三重四极杆质谱(HPLC-MS/MS)仪建立了同时分析烟叶中吲哚乙酸(IAA)、吲哚丁酸(IBA)、水杨酸(SA)、赤霉素(GA)、茉莉酸(JA)、脱落酸(ABA)和油菜素内酯(BR)等7种植物激素质量分数的方法。采用多离子反应检测模式,获得7种植物激素的特征碎片离子峰,并测定了烟草花叶病毒(TMV)感染的烟叶样品。结果表明:(1)7种植物激素在线性范围内的相关系数(r)为0.998 6～0.999 5,方法的检出限为0.07～3.00μg/L,日内日间相对标准偏差(RSD)为0.44%～9.76%,回收率为77.82%～117.63%;(2)烟草花叶病毒感染极显著(p<0.01)地增加了烟叶中SA、IBA、JA、ABA的质量分数,显著(p<0.05)增加了烟叶中IAA的质量分数,同时显著(p<0.05)降低了烟叶中GA的质量分数;TMV病毒感染对BR的影响不大。该方法具有良好的灵敏度、精密度和回收率,可用于植物相关激素的同时分析。

新农药联苯肼酯的光化学降解

以紫外灯和氙灯为光源对联苯肼酯的光化学降解进行研究,利用高效液相色谱-二极管阵列检测法(HPLC-DAD)进行定性和定量分析,利用气质联用技术GC-MS)对联苯肼酯光降解产物进行初步推断.实验结果表明,在紫外灯光照下联苯肼酯在正己烷、乙腈、丙酮、水中的半衰期分别为3.60—7.67 min、3.64—10.30 min、16.31—26.45 min、23.02 min;在氙灯照射下联苯肼酯在正己烷、乙腈、丙酮、水中的半衰期分别为0.36—0.53 h、0.91—1.30 h、1.50—2.53 h、5.02 h.在两种光源照射下联苯肼酯在所有溶液中的光降解反应均符合一级反应动力学规律,光解速率为:正己烷>乙腈>丙酮>水,联苯肼酯的光降解反应初步推断为氧化、水解反应.影响其降解速率的主要因素是光源、溶剂的种类以及溶液的初始浓度.

液相色谱-串联四极杆飞行时间质谱和超高效液相色谱-串联三重四极杆质谱用于检测牛肉中的刚果红

建立了牛肉中刚果红的检测方法。定性方法采用液相色谱-串联四极杆飞行时间质谱对未知物进行质谱谱图库匹配,定量分析采用超高效液相色谱-串联三重四极杆质谱。牛肉样品中的刚果红经液液萃取净化后,采用Agilent ZORBAX Eclipse Plus C18Rapid Resolution HD色谱柱(50mm×2.1mm,1.8μm)进行分离,流动相为95%(体积分数)甲醇,流速为0.2mL/min。AB 4000+三重四极杆质谱仪在电喷雾负离子化(ESI)及MRM模式下定量。结果显示,刚果红在0.03～1mg/L浓度范围内,线性关系良好(相关系数为0.999 8),精密度良好(RSD小于5%),回收率为88%～91%,检出限约为0.01mg/L。本方法快速简便,重现性好,可以为牛肉及其他肉制品中刚果红的定量提供良好的解决方案。

高效液相色谱-串联质谱法测定水产品中甲氧苄啶的残留

建立水产品中甲氧苄啶药物残留量测定的高效液相色谱-串联质谱方法。样品选择乙腈提取，用正己烷脱脂，固相萃取柱净化，采用LC-MS/MS选择反应监测（SRM）正离子模式测定进行定性、定量分析。结果表明：甲氧苄啶药物的检出限（LOD）为0.5μg/kg，定量限（LOQ）为1.0μg/kg，检测结果的相对标准偏差为1.78%-5.08%，加标回收率达到77.1%-93.5%。该方法具有比较高的重现性和选择性，在水产品中甲氧苄啶的残留测定中具有很好的应用前景。

液-质联用测定不同产地独活中蛇床子素和欧前胡素的含量

目的建立不同产地独活中蛇床子素和欧前胡素含量的测定方法。方法采用液相色谱-质谱联用（液-质联用）方法,测定4种不同产地独活中蛇床子素和欧前胡素的含量。液相色谱条件：甲醇-水（体积比,85∶15）作流动相,流速为0.3 m L·min^-1,柱温30℃,进样量5μL。质谱条件：电喷雾离子源（ESI）,阳离子模式,多反应监测（MRM）方式检测。采用外标法测定蛇床子素和欧前胡素的含量。结果不同产地独活中蛇床子素含量范围为1.11~5.02μg·g^-1,欧前胡素的含量范围0.85~9.54μg·g……-1。结论不同产地独活中蛇床子素和欧前胡素的含量存在一定的差异。该法可为不同地区独活中药材的质量控制提供参考标准。

微波辅助萃取/超高效液相色谱-静电场轨道阱高分辨质谱法同时测定纺织品中的抗菌剂和紫外光稳定剂

建立了超高效液相色谱-静电场轨道阱高分辨质谱（UPLC-Orbitrap HRMS）同时测定纺织品中7种抗菌剂和7种紫外光稳定剂含量的分析方法。以甲醇为萃取溶剂,85℃下微波萃取纺织品中的抗菌剂和紫外光稳定剂,萃取液经浓缩定容后进行UPLC/Orbitrap HRMS分析,外标法定量。以甲醇-0.1%甲酸水溶液（含5 mmol/L乙酸铵）为流动相,14种目标化合物在Hypersil GOLD色谱柱（100 mm×2.1 mm,1.9μm）上进行梯度洗脱。一级质谱扫描范围为m/z 100-500,14种目标化合物的质量数准确度误差均小于2×10-6（2ppm）,其中对氯间二甲酚（PCMX）和三氯生采用电喷雾负离子模式,其余12种目标化合物均采用电喷雾正离子模式。通过目标化合物的保留时间和准分子离子峰的精确质量数进行定性,提取离子色谱图的峰面积进行定量。在各自的线性范围内,每种目标化合物的提取离子色谱图的峰面积均与其质量浓度线性相关,相关系数均大于0.998。在3个不同的加标浓度水平下,方法的平均加标回收率为80.1%-95.6%,相对标准偏差为2.9%-10.5%。方法的检出限（S/N=3）为0.1-0.3μg/kg。该方法定性可靠,定量准确,检出限低,完全可满足纺织品中抗菌剂和紫外光稳定剂含量检测的需要。

高效液相色谱-串联质谱法测定生活饮用水中11种抗生素

目的建立固相萃取-高效液相色谱-串联质谱法测定生活饮用水中磺胺醋酰、磺胺嘧啶、氧氟沙星、恩诺沙星等11种抗生素。方法选用Agilent ZORBAX Eclipse Plus C18色谱柱,以10 mmol/L甲酸铵-0.1%甲酸(A)和甲醇(B)为流动相,采用梯度洗脱进行分离。样品经过固相萃取小柱富集,多重反应监测(multiple reaction monitoring,MRM)方式检测,外标法定量。结果 11种抗生素在1.0~200.0 ng/m L范围内线性关系良好,平均回收率在45.9%~109.6%。结论该方法灵敏度高,选择性好,准确可靠,方便快捷,适用于水体中抗生素残留的定量定性分析。