分散固相萃取-液相色谱-串联质谱法测定农产品中吡氟甲禾灵

应用液相色谱-串联质谱联用技术,建立了农产品中吡氟甲禾灵的分析方法.样品经乙腈提取,无水Mg2SO4和NaCl混合盐盐析,N-丙基乙二胺、C18填料分散固相萃取净化;采用乙腈和5 mmol/L甲酸铵水溶液为流动性,二元梯度洗脱,C18(2.1×150 mm,3.5 μm)色谱柱分离;电喷雾正离子模式采集,多反应监测模式...     

Determination of quaternary ammonium compounds in seawater samples by solid-phase extraction and liquid chromatography-mass spectrometry

A method for the simultaneous determination of two biocidal quaternary ammonium compounds; didecyldimethylammonium chloride (didecyldimethyl quat) and dodecylbenzyldimethylammonium chloride (benzyl quat), in seawater by solid phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS) was developed. The optimised procedure utilised off-line extraction of the analytes from seawater using polymeric (Strata-X) SPE cartridges. Recoveries ranged from 80 to 105%, with detection limits at the low parts-per-trillion (ng/l) level for both analytes. To demonstrate sensitivity, environmental concentrations were measured at three different locations along the North East coast of England with measured values in the range 120-270ng/l.     

固相萃取-高效液相色谱-串联质谱法检测香辛料中罗丹明B

建立了香辛料中罗丹明B的固相萃取-高效液相色谱-串联质谱分析方法。样品经乙腈提取后离心,在提取液中加入10 mL 1%三氯乙酸溶液后,用Bond Elut Plexa PCX强阳离子固相萃取柱净化、富集,Pursuit C18色谱柱(100 mm×2.0 mm, 3 μm)分离,以0.1%甲酸水和甲醇为流动相梯度洗脱,电喷雾电离正离子模式下多反应监测(MRM)模式进行定性、定量检测。结果表明,在0.6～6 μg/L范围内的线性相关系数R2＞0.99;方法的定量限为1.2 μg/kg;添加量分别为1.197、2.992及5.985 μg/L时的加标回收率为80%～121%,相对标准偏差＜15%。同时对流动相的洗脱梯度、提取溶剂、固相萃取柱等条件进行了优化。该方法的专属性较强,基质效应较小,可用于固体香辛料产品中罗丹明B的定性、定量分析。     

固相萃取-液相色谱-串联质谱法同时测定水中14种短链和长链全氟化合物

建立了固相萃取-超高压液相色谱-三重四极杆质谱同时测定水中14种短链和长链全氟化合物（PFCs）的方法。水样经WAX混合型固相萃取小柱富集和净化后,采用BEH C18色谱柱、甲醇和5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,质谱采用多反应监测模式,内标法定量分析。14种PFCs在0.1~50 μg/L范围内线性关系良好,相关系数大于0.99,方法检出限和定量限分别为0.09~1.15 ng/L和0.29~3.85 ng/L。在2、10和20 ng/L加标水平下,8种PFCs的平均回收率为85.0%、120.2%和117.4%,平均相对标准偏差为9.2%、9.0%和6.6%,6种PFCs的回收率相对较低,主要由于其在瓶/管壁上的吸附作用导致。应用本方法分析某淡水湖水样,检出4种短链和5种长链PFCs,质量浓度为41.29~49.05 ng/L和98.43~111.02 ng/L。结果表明该方法适用于对环境水体中短链和长链PFCs的同时分析测定。     

蔬菜中阔草清等8种农药残留量的高效液相色谱-质谱分析

建立了固相萃取-高效液相色谱-电喷雾质谱法同时测定蔬菜中的阔草清、西玛津、硫双威、绿麦隆、扑草净、仲丁威、马拉硫磷和二嗪农等8种农药的分析方法.蔬菜用乙腈超声波提取,经过ODS-C18固相萃取小柱富集纯化.采用C18柱分离,以体积分数0.03%甲酸乙腈-体积分数0.03%甲酸水溶液为流动相,线性梯度洗脱,以保留时间和质荷比对分离出的组分进行定性,用峰面积进行定量.结果表明,8种农药的质量浓度与其峰面积在一定的范围内呈良好的线性关系,检出限为0.1～5.0 μg/L,相关系数为0.9939～0.9998,样品的加标平均回收率为83%～106%,相对标准偏差为3.1%～9.8%.方法适用于蔬菜中阔草清等8种农药残留量的分析.     

Determination of flunitrazepam and 7-aminoflunitrazepam in human urine by on-line solid phase extraction liquid chromatography-electrospray-tandem mass spectrometry

A method using an on-line solid phase extraction (SPE) and liquid chromatography with electrospray-tandem mass spectrometry (LC-ES-MS/MS) for the determination of flunitrazepam (FM2) and 7-aminoflunitrazepam (7-aminoFM2) in urine was developed. A mixed mode Oasis HLB SPE cartridge column was utilized for on-line extraction. A reversed phase C₁₈ LC column was employed for LC separation and MS/MS was used for detection. Sample extraction, clean-up and elution were performed automatically and controlled by a six-port valve. Recoveries ranging from 94.8 to 101.3% were measured. For both 7-aminoFM2 and FM2, dual linear ranges were determined from 20 to 200 and 200-2000 ng/ml, respectively. The detection limit for each analyte based on a signal-to-noise ratio of 3 ranged from 1 to 3 ng/ml. The intra-day and inter-day precision showed coefficients of variance (CV) ranging from 4.6 to 8.5 and 2.6-9.2%, respectively. The applicability of this newly developed method was examined by analyzing several urine samples.     

固相萃取-超高效液相色谱-串联质谱法测定蜂产品中10种头孢类药物

建立了蜂产品中10种头孢类药物（头孢喹肟、头孢噻肟、头孢洛宁、头孢哌酮、头孢匹林、头孢氨苄、头孢乙腈、头孢拉定、去乙酰基头孢匹林、头孢唑林）含量的液相色谱-串联质谱测定方法。蜂产品样品中头孢类药物用乙腈-水（80：20,v/v）溶液提取,离心,上清液经Oasis PRIME HLB固相萃取柱净化,氮吹后复溶,进行液相色谱-串联质谱分析。采用Acquity BEH C18色谱柱,以0.1%（v/v）甲酸水溶液-甲醇体系作为流动相进行梯度洗脱,ESI源正离子模式电离,多反应离子监测模式（MRM）检测,基质校准外标法定量。结果表明,10种头孢类药物在一定浓度范围内峰面积与质量浓度的相关系数（r²）大于0.999,线性关系良好;检出限为0.15~1.5 μg/kg,定量限为0.50~5.0 μg/kg;在阴性蜂产品样品中的加标回收率为75.0%~89.8%,相对标准偏差（RSD）为1.4%~4.6%（n=5）。该方法检测周期短,准确度和精密度高,能满足多种蜂产品样品中头孢类药物的检测需要。     

New dispersive solid phase extraction sorbent of graphitic carbon nitride for field evaluation and dissipation kinetics of pesticides in wheat ecosystem by liquid chromatography tandem mass spectrometry

Nanosheets of graphitic carbon nitride (GCN) were used as the dispersive solid-phase extraction (d-SPE) sorbent for the first time. GCN successfully purified complex matrices of soil, wheat, and wheat straw utilising a simple QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with liquid chromatography tandem mass spectrometry. Pesticides recoveries in the range of 80–110%, small matrix effect, and decreased amounts guaranteed and distinguished this new sorbent. The application of a real formulation of pesticides under field conditions during 2015 in the wheat ecosystem illustrated the clean-up effect and application potential of GCN. It is a valuable and potential substitute for C18 according to the results comparison between two sorbents, including recoveries, matrix-matched calibration, and dissipation kinetics of pesticides. The new use of GCN also enriched the knowledge of d-SPE and sample preparation furthermore.     

环境水样中9种三唑类农药的固相萃取-气相色谱-质谱分析

应用C18柱萃取/富集,NH2柱净化,气相色谱-质谱联用技术检测,建立了环境水样中9种三唑类农药同时分析的方法。9种目标农药在0.025～0.500 mg/L质量浓度范围内线性关系良好,方法的检出限为0.002～0.009 μg/L。以实际水样为基底,加标质量浓度为0.025 μg/L和0.100 μg/L时,9种目标农药的基底加标回收率和相对标准偏差(n=3)分别为68.4%～113.9%,1.6%～6.9%(河水)和70.3%～115.2%,0.8%～8.2%(海水)。该方法操作简单、灵敏度高、选择性好,符合多种农药残留分析的要求,并成功地应用于福建九龙江河口区表层水样中三唑类农药的残留状况调查。     

固相萃取-气相色谱-质谱联用检测地沟油中胆固醇

建立了固相萃取-气相色谱-质谱联用(SPE-GC-MS)检测地沟油样品中胆固醇的分析方法。样品用硅胶固相萃取小柱前处理净化,先用20 mL含0.6%乙醚的正己烷溶液淋洗,再用10 mL含15%乙醚的正己烷溶液洗脱,胆固醇萃取率达97%。净化后的样品用配备电子轰击离子源的气相色谱-质谱联用仪进行测定,以保留时间和特征碎片离子定性,在选择离子监测模式下用外标法定量,选择离子为m/z 213、275、301、368、386,目标离子为m/z 386,参考离子为m/z 213和275。不同加标水平下的加标回收率为91.7%～101%,相对标准偏差(RSD)小于6%,检出限为0.01 mg/L。胆固醇质量浓度在0.24~6.0 mg/L范围内有良好的线性关系(相关系数为0.9996)。该法可精确检测油脂中胆固醇的含量,检测结果可作为判断其中是否掺有地沟油的依据之一。     

Determination of fungicides in wine by mixed-mode solid phase extraction and liquid chromatography coupled to tandem mass spectrometry

A novel procedure for the determination of nine selected fungicides (metalaxyl-M, azoxystrobin, myclobutanil, flusilazole, penconazole, tebuconazole, propiconazole, diniconazole and difenoconazole) in wine samples is presented. Sample enrichment and purification is simultaneously performed using mixed-mode, anion exchange and reversed-phase, OASIS MAX solid-phase extraction (SPE) cartridges. Analytes were determined by liquid chromatography coupled to tandem mass spectrometry using atmospheric pressure electrospray ionization (LC-ESI-MS/MS). Parameters affecting the chromatographic determination and the extraction-purification processes were thoroughly investigated. Under optimized conditions, 10 mL of wine were firstly diluted 1:1 with ultrapure water and then passed through the mixed-mode SPE cartridge at a flow of ca. 5 mLmin(-1). After a washing step with 5 mL of an aqueous NH(4)OH solution (5%, w:v), analytes were recovered with just 1 mL of methanol and injected in the LC-MS/MS system without any additional purification. The selective extraction process avoided significant changes in the ionization efficiency for red and white wine extracts in comparison with pure standards in methanol. Performance of the method was good in terms of precision (RSDs<11%) and accuracy (absolute recoveries>72%, determined against pure standards in methanol) reporting method LOQs in the range of 0.01-0.79 ngmL(-1) for target compounds, which are far below the EU maxima residue levels (MRLs) for fungicides in vinification grapes and wine. Several commercial wines from different geographic areas in Spain were analyzed. In most samples, metalaxyl-M and azoxystrobin were found at concentrations up to several ngmL(-1).     

Multiresidue determination of 160 pesticides in wines employing mixed-mode dispersive-solid phase extraction and gas chromatography-tandem mass spectrometry

A new multiresidue method for the efficient screening, identification and quantification of over 160 pesticides belonging to different chemical classes in red, rose and white wines have been developed. The analysis was based on gas chromatographic-tandem quadrupole mass spectrometric determination (GC-QqQ-MS/MS). An optimization strategy involved the selection of buffering conditions and sorbents for dispersive-solid phase extraction (dispersive-SPE) in order to achieve acceptably high recoveries and reduce co-extractives in the final extracts. As a result, the optimized procedure allowed us to obtain consistent recoveries of the target pesticides including problematic ones such as captan, chlorothalonil, dichlofluanid, folpet and tolylfluanid. The attained recoveries were typically between 80 and 110% (89% on average) with RSD values typically lower than 10% (8% on average) at three spiking levels of 0.01, 0.05 and 0.2 mg kg⁻¹. Linearity was studied in the range between 0.005 and 0.2 mg kg⁻¹ using pesticide standards prepared both in pure solvent and in the presence of matrix, showing coefficients of determination (R²) higher than 0.99 for all the pesticides except for desmedipham, thiabendazole and thiamethoxam in pure solvent. The study of the ratio of the slopes obtained in solvent and in matrix provided information about the matrix effects, which was <10%, 10-20% and >20% for 33, 36 and 31% of the studied pesticides, respectively. To improve accuracy, matrix matched standards were always used for calculation of the quantification results. The expanded uncertainties were estimated by using a “top-down” approach as being 17% on average (coverage factor k = 2, confidence level 95%). Finally, the method was used with success to detect and quantify pesticide residues in commercial wines.     

固相萃取-高效液相色谱/串联质谱法测定食醋中的3种甜味剂

建立了食醋中3种甜味剂的固相萃取-高效液相色谱/串联质谱分析方法。样品经酸性水稀释,弱阴离子固相萃取柱净化,Pursuit C18色谱柱分离,10 mmol/L醋酸铵(含0.1%氨水)和乙腈为流动相梯度洗脱,电喷雾负离子模式下多反应监测(MRM)模式检测。糖精钠、安赛蜜、甜蜜素的定量限分别为10、5、5 μg/kg,回收率为72.1%～96.8%,相对标准偏差小于15%。该方法准确、灵敏度高,可用于食醋中甜味剂的定性定量检验。     

固相萃取-气相色谱-质谱联用同时测定河水和海水中87种农药

采用固相萃取-气相色谱-质谱联用技术,建立了河水和海水中87种农药(24种有机磷、15种有机氯、12种唑类、9种拟除虫菊酯类、5种氨基甲酸酯类、7种酰胺类及15种其他新型农药)的多残留同时分析方法。优化了影响分离效果和灵敏度的仪器参数,考察了固相萃取柱柱型及水样体积、pH、盐度的影响,采用NH2柱优化了净化效果,内标法和替代物法用于数据的质量控制。结果表明: 在最佳条件下,各目标农药的方法检出限为0.1～6.6 ng/L;以实际河水和海水为基底,在5 ng/L和20 ng/L的加标水平下,绝大多数目标农药的回收率为60%～120%,相对标准偏差(n=4)为0.01%～9.7%。该法灵敏、准确,已成功地应用于福建九龙江河口区表层水样中多种类农药的复合污染监测,检出包括5种有机磷类、3种酰胺类、4种唑类、3种氨基甲酸酯类、2种拟除虫菊酯类等农药20种。     

串联固相萃取-液相色谱-串联质谱法测定食品中嘧啶胺类杀菌剂残留

建立了食品中嘧啶胺类杀菌剂嘧霉胺、嘧菌胺及嘧菌环胺残留的串联固相萃取-液相色谱-串联质谱(HPLC-MS/MS)检测方法。胡萝卜、辣椒等样品经乙酸乙酯提取,石墨化炭黑-弗罗里硅藻土串联固相萃取柱(ENVI-Carb-Florisil SPE)净化后,在HPLC-MS/MS仪上进行检测分析,采用外标法定量。质谱分析采用电喷雾电离,正离子扫描,多反应监测模式。结果表明,柱净化后无明显的基质效应,嘧霉胺、嘧菌胺和嘧菌环胺在1～20 μg/L内相关系数可达0.9990以上,具有良好的线性关系;每种杀菌剂选择两个离子对,其中一组用于定量: 嘧霉胺m/z 200.1/107.1,嘧菌胺m/z 224.0/106.0及嘧菌环胺m/z 226.0/108.1;另一组用于确证: 嘧霉胺m/z 200.1/183.1,嘧菌胺m/z 224.0/131.1和嘧菌环胺m/z 226.0/133.1。样品中添加0.1、0.5、1.0 μg/kg的标准品,其回收率为73.2%～98.7%,相对标准偏差(n=10)小于10%;嘧霉胺、嘧菌胺、嘧菌环胺的检出限(信噪比(S/N)=3)均为0.03 μg/kg;嘧霉胺、嘧菌胺、嘧菌环胺的定量限(S/N=10)均为0.1 μg/kg。实验结果表明,该方法提取效果好,具有良好的灵敏度、回收率和重复性。     

固相萃取高效液相色谱质谱法测定海水中烷基酚和烷基酚聚氧乙烯醚

建立了固相萃取-高效液相色谱-电喷雾质谱分析海水中辛基酚、壬基酚、辛基酚聚氧乙烯醚和壬基酚聚氧乙烯醚的方法。海水样品经C18固相萃取柱富集净化后,以甲醇-水为流动相,在Hypersil GOLD色谱柱上分离,电喷雾质谱在选择离子监测模式下分析目标化合物,采用外标法定量。结果表明,4种化合物的平均加标回收率为59.6%～104.4%,相对标准偏差(RSD, n=3)为1.0%～13.5%;仪器检出限为0.08～3 μg/L。将本方法用于大连海岸6个采样点海水中辛基酚、壬基酚、辛基酚聚氧乙烯醚和壬基酚聚氧乙烯醚的检测发现,样品中壬基酚和壬基酚聚氧乙烯醚均有检出,且油港和海港附近海水中的含量较高。     

固相萃取-超高效液相色谱-串联质谱法检测环境水体中18种农药残留

建立了固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)同时检测环境水体中不同极性范围的18种农药残留的分析方法。样品经大体积固相萃取装置,以2 mL/min的速率通过Cleanrt■-PEP固相萃取柱进行净化和富集,浓缩50倍后结合UPLC-MS/MS检测,外标法定量。研究表明,目标化合物在0.5～50μg/L范围内线性关系良好,线性相关系数(R²)≥0.995;在10、100和1 000 ng/L 3个添加水下,18种农药在3种不同环境水体中的平均回收率为71.3%～105.9%,相对标准偏差(RSD,n=5)为1.3%～9.9%;定量限(LOQ)均为10 ng/L。该方法应用于泰安市区周围水环境的检测,各采集位点均未检出农药残留。该方法具有净化效果好、通用性强、灵敏度高、准确度高和操作简单等优点,适用于环境水体中18种农药的残留检测。     

Accurate analysis of trace earthy-musty odorants in water by headspace solid phase microextraction gas chromatography-mass spectrometry

A simple and sensitive method was developed for the simultaneous separation and determination of trace earthy-musty compounds including geosmin, 2-methylisoborneol, 2-isobutyl-3-methoxypyrazine, 2-isopropyl-3-methoxypyrazine, 2,3,4-trichloroanisole, 2,4,6-trichloroanisole, and 2,3,6-trichloroanisole in water samples. This method combined headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry and used naphthalene-d(8) as internal standard. A divinylbenzene/carboxen/polydimethylsiloxane fiber exposing at 90°C for 30 min provided effective sample enrichment in HS-SPME. These compounds were separated by a DB-1701MS capillary column and detected in selected ion monitoring mode within 12 min. The method showed a good linearity from 1 to 100 ng L(-1) and detection limits within (0.25-0.61 ng L(-1)) for all compounds. Using naphthalene-d(8) as the internal standard, the intra-day relative standard deviation (RSD) was within (2.6-3.4%), while the inter-day RSD was (3.5-4.9%). Good recoveries were obtained for tap water (80.5-90.6%), river water (81.5-92.4%), and lake water (83.5-95.2%) spiked at 10 ng L(-1). Compared with other methods using HS-SPME for determination of odor compounds in water samples, this present method had more analytes, better precision, and recovery. This method was successfully applied for analysis of earthy-musty odors in water samples from different sources.     

分散固相萃取-液相色谱-串联质谱法测定谷物、蔬菜、水果中27种新型杀菌剂

建立了同时检测谷物、蔬菜和水果中27种新型杀菌剂的分散固相萃取-液相色谱-串联质谱(DSPE-LC-MS/MS)分析方法。样品经1%(体积分数)乙酸丙酮溶液提取,以无水硫酸镁(MgSO_4)脱水,经N-丙基乙二胺(PSA)、C_(18)、无水MgSO_4、多壁碳纳米管(MWCNT)混合净化剂净化,经C_(18)色谱柱分离,用乙腈和体积分数为0.1%的甲酸水溶液(含5 mmol/L乙酸铵)梯度洗脱,多反应监测(MRM)正离子模式扫描,采用外标法定量。噻呋酰胺和氯啶菌酯在20.47~200μg/kg范围内线性关系良好,其他25种新型杀菌剂在0.02~100μg/kg范围内线性关系良好,相关系数R~2≥0.995 0,加标回收率为70.02%~117.6%,相对标准偏差(RSD)为0.01%~19.62%(n=3)。噻呋酰胺和氯啶菌酯的检出限为6.15~16.67μg/kg,定量限为20.47~55.5μg/kg。其他25种新型杀菌剂的检出限为0.006~4.44μg/kg,定量限为0.02~14.79μg/kg。该方法简便、快速、可靠,可用于谷物、蔬菜、水果中27种新型杀菌剂的快速测定。     

固相萃取-高效液相色谱-串联质谱法测定畜禽粪便中的残留抗生素

建立了固相萃取-高效液相色谱-串联质谱法(HPLC-MS/MS)同时测定畜禽粪便中四环素类化合物(四环素、金霉素、土霉素)、喹诺酮类化合物(诺氟沙星、环丙沙星、洛美沙星)和磺胺二甲嘧啶7种抗生素的检测方法。样品中的抗生素用含有甲醇、乙酸和水(6:3:1, 体积比)的混合溶液提取后,经HLB固相萃取小柱纯化富集,采用Symmetry C₁₈色谱柱分离,0.3%甲酸水溶液和0.3%甲酸乙腈溶液作为流动相进行梯度洗脱,电喷雾正离子(ESI⁺)模式电离,多反应监测(MRM)模式检测,外标法定量。结果表明,四环素类化合物和喹诺酮类化合物在50~1000 μg/L、磺胺二甲嘧啶在5~100 μg/L的范围内具有良好线性。3倍信噪比下,四环素类化合物、喹诺酮类化合物和磺胺二甲嘧啶的检出限分别为0.25~7.18、0.15~3.16和0.04 μg/kg。在猪粪和鸡粪样品中添加0.1~10 μg/g水平的四环素类化合物、喹诺酮类化合物和磺胺二甲嘧啶,其平均添加回收率为40%~124%,相对标准偏差(RSD)为3.0%~9.5%。采用该方法对部分养殖场的猪粪和鸡粪进行了检测,结果表明,四环素类化合物均有不同程度的检出,喹诺酮类化合物和磺胺二甲嘧啶有部分检出。该方法具有灵敏度和准确度高的特点,可满足畜禽粪便中四环素类化合物、喹诺酮类化合物及磺胺二甲嘧啶的检测。