加速溶剂萃取-气相色谱串联质谱法检测沉积物中痕量增塑剂

研究了加速溶剂萃取(ASE)对沉积物中邻苯二甲酸酯类(PAEs)物质的提取效果,建立了快速溶剂萃取/气相色谱-质谱联用(GC/MS)检测沉积物中16种邻苯二甲酸酯类物质的方法。用正己烷和二氯甲烷混合溶剂作为提取溶剂,加速溶剂萃取法萃取沉积物中16种PAEs,再用Florisil层析柱净化,最后用GC/MS对净化后提取液中的PAEs进行定量分析。结果表明:当萃取剂为二氯甲烷-正己烷(1∶1,V/V),萃取温度为80℃时,萃取效率最高,16种PAEs的回收率稳定在81.2%～128.5%之间,相关系数≥0.99,检出限为0.12～0.98 ng/g,相对标准偏差为1.1%～10.8%。加速溶剂萃取法与传统索氏提取法相比,既提高了萃取效率同时又减少了有机萃取溶剂的用量。在检测实际样品时,同时加入3种内标指示剂对方法的性能进行了验证,3种内标的回收率分别为106.0%±18.8%,87.4%±10.8%和81.4%±14.5%,样品中16种PAEs的检出率为100%。前处理方法处理简单,定性与定量分析准确可靠。     

分散式固相萃取净化-气相色谱-质谱联用测定土壤中的邻苯二甲酸酯

建立了土壤中18种邻苯二甲酸酯类内分泌干扰物的微波提取-分散式固相萃取净化-GC/MS分析方法.10 g土壤样品经20 mL二氯甲烷和丙酮混合溶剂微波提取后,以丙酮为置换溶剂并浓缩至1.5 mL.浓缩液中加入0.2 g C18吸附剂,振摇3 min后离心10 min(8000 r/min),取1.0 mL上层清液经正己烷置换后用气相色谱-质谱联用分析,并通过基质标准加入校准曲线补偿邻苯二甲酸酯的基体效应.净化所需时间少于20 min.净化后土壤萃取液的基质去除率达到72.7%.方法线性范围7.5～750 μg/kg,相关系数大于0.998; 6次土壤样品测定值的RSD在5.5%～12.1%之间; 加标土壤样品测定值RSD在7.3%～19.4%之间; 平均回收率在94.4%～114.6%之间; 检出限为1.2～4.3 μg/kg.     

超声提取/气相色谱-质谱法测定海洋生物中的多环芳烃

建立了海洋生物体中16种优先控制多环芳烃的超声提取/气相色谱-质谱测定方法,对海洋鱼类、虾类、贝类和蟹类等生物样品的提取、净化和色谱质谱条件进行了优化。以正己烷-二氯甲烷(2∶1)作为溶剂进行超声提取,提取液经60%硫酸溶液和中性氧化铝-弗罗里硅土混合层析柱净化,采用气相色谱-质谱法定性和定量分析。在优化条件下,16种多环芳烃的线性范围为0.005～0.500 mg/L,相关系数(r)不低于0.998 4,检出限为0.03～0.28μg/kg。加标水平为2、20、100μg/kg时,平均加标回收率分别为55%～118%、80%～114%和79%～113%,相对标准偏差(RSDs,n=6)均小于10%。该方法快速、准确、灵敏度高、重复性好,能满足海洋生物体中持久性有机污染物分析的要求。     

气相色谱-质谱法测定水产品中24种邻苯二甲酸酯类化合物

建立了同时测定水产品中24种邻苯二甲酸酯类化合物(PAEs)的气相色谱-质谱(GC-MS)分析方法。称取1.0 g样品于10 mL玻璃离心管中,加内标D4-DEHP溶液(10 mg/L)100μL,氯化钠0.5 g,以5 mL乙腈-乙酸乙酯(1∶1)超声提取5 min,4 000 r/min离心5 min,移取上层有机相。再加入3 mL乙腈-乙酸乙酯重复提取。合并两次的提取液浓缩至1～2 mL后,经Florisil玻璃固相萃取柱净化,洗脱液在50℃下氮吹至近干,用正己烷超声溶解定容至1 mL,供GC-MS分析。24种PAEs的定量下限(LOQ)为1～500μg/kg,检出限(LOD)为0.1～100μg/kg。选取鱼、虾为研究基质考察方法的准确度及精密度,24种PAEs在3个添加水平时的平均回收率及相对标准偏差(n=6)分别为73%～120%、2.0%～19.7%。结果表明,该方法提取效率高,净化效果好,重复性强,能够满足水产品中邻苯二甲酸酯类化合物的检测需求。     

液相色谱-串联质谱法同时测定大黄鱼中20种磺胺类药物残留

建立了一种液相色谱-电喷雾串联质谱同时测定大黄鱼中20种磺胺类药物残留的方法.均质样品先后用乙腈、二氯甲烷提取,合并提取液,取部分提取液经氮吹浓缩.残渣用1 mL流动相溶解,饱和正己烷脱脂净化.采用ZORBAX Eclipse XDB-C8色谱柱,以含0.2%乙酸的水溶液和甲醇(7: 3)为流动相,梯度洗脱,在电喷雾-多反应监测离子模式下,进行定量定性分析.方法的定量限为5 μg/kg;以标准加入法计算回收率,在10～40 μg/kg添加范围内,平均回收率为79.6%～109%;相对标准偏差为3.55%～16.5%.     

快速溶剂萃取-气相色谱-质谱法同时测定土壤中多环芳烃、六六六和滴滴涕

建立快速溶剂萃取-气相色谱-质谱法同时测定土壤中多环芳烃、六六六和滴滴涕。优化了提取溶剂和洗脱溶剂,采用加速溶剂萃取法处理土壤样品,萃取溶剂为二氯甲烷-正己烷(1∶1)。提取液用氮吹仪浓缩、硅酸镁固相萃取小柱净化,用二氯甲烷-正己烷(3∶7)混合溶剂对固相萃取小柱进行活化和洗脱,流出液净化后氮吹浓缩至1 mL,利用气相色谱-质谱内标法进行分析定量。16种多环芳烃、8种有机氯农药及3种替代物在5.0～500μg/L范围内线性良好,方法检出限为0.000 55～0.000 77 mg/kg,加标回收率为68.2%～112.7%,相对标准偏差为4.3%～10.1%(n=5)。该方法可用于同时测定土壤中多环芳烃、六六六、滴滴涕的含量。     

气相色谱-串联质谱法测定土壤中的邻苯二甲酸酯

建立了土壤中6种邻苯二甲酸酯的气相色谱-串联质谱(GC-MS/MS)分析方法。土壤样品用超声提取,以二氯甲烷-丙酮(1:1, v/v)混合溶液为提取溶剂,提取液经Florisil小柱净化后,经HP-5MS色谱柱(30 m×0.25 mm×0.25 μm)分离,利用MS/MS的多反应监测(MRM)模式进行定性和定量。结果表明本方法可对样品中的邻苯二甲酸酯进行分析,在10～1000 μg/L质量浓度范围内,线性关系良好,相关系数为0.9973～0.9976;6种邻苯二甲酸酯的相对标准偏差(RSD)不大于14.3%, 2 μg/kg和10 μg/kg两个加标水平的回收率为72.9%～106.2%; 6种目标化合物的检出限为0.1～0.5 μg/kg。该方法快速准确、背景干扰较少、分析灵敏度较高,适用于土壤样品中邻苯二甲酸酯的分析。     

GC-MS法测定粮谷及油料中55种有机磷农药残留量

采用ASE-300快速溶剂萃取仪提取样品中农药残留量,提取液经二氯甲烷液-液分配、凝胶色谱柱（GPC）净化,固相萃取柱（活性炭）再净化,浓缩定容后,用气相色谱-质谱仪（GC-MS）测定,外标法定量.采用选择离子检测进行阳性确证.选择玉米、糙米、大豆、花生为实验样品、敌敌畏等55种农药添加水平在0.5～2.00 mg/kg时,该方法回收率为68%～117%;精密度为4.04%～11.76%;方法测定低限为0.005～0.100 mg/kg,各项指标均满足有关要求.     

液相色谱-串联质谱法同时测定纺织品和食品包装材料中的壬基酚、辛基酚和双酚A

建立了纺织品和食品包装材料中壬基酚、辛基酚和双酚A的液相色谱-串联质谱分析方法。不同类型的纺织品和食品包装材料样品采用加速溶剂萃取法,以无水乙醇为提取剂,在10.3 MPa和120℃下静态循环提取2次,提取液经Supelclean Envi-Carb石墨化碳黑固相萃取柱净化,收集甲醇-二氯甲烷(1∶4,V/V)洗脱液,采用Waters XBridge C18色谱柱,以甲醇-0.1%氨水溶液为流动相,梯度洗脱分离后,在LC/MS/MS多反应监测模式下进行定性与定量分析。壬基酚、辛基酚和双酚A的方法检出限为0.5μg/kg,在0.5～10μg/kg的3个添加水平范围内,纺织品样品的平均回收率为86.9%～92.5%,相对标准偏差均小于9.1%;食品包装材料样品的平均回收率为87.8%～93.0%,相对标准偏差均小于8.8%。本方法准确、快速、灵敏度高,可用于纺织品和食品包装材料的实际检验。     

同位素稀释三重串联四级杆质谱法测定鱼组织中24种多环芳烃

采用气相色谱-三重串联四级杆质谱联用技术测定了鱼组织中24种多环芳烃(PAHs).将冻干鱼组织样品加入同位素内标后,用加速溶剂萃取法(ASE)进行提取,提取液采用凝胶排阻色谱(GPC)和固相萃取(SPE)联用进行净化.采用二氯甲烷为提取溶剂,100℃下提取,以二氯甲烷作为GPC的流动相,在3.5 mL/min流速下,收...     

Comparison of extraction techniques for isolation of steroid oestrogens in environmentally relevant concentrations from sediment

The comparison of four extraction techniques for isolation of five native and one labelled steroid oestrogens from sediment was described. The three conventional extraction techniques Soxhlet warm extraction (SWE), accelerated solvent extraction (ASE), microwave-assisted extraction (MAE) and a promising technique QuEChERS were tested for isolation of low environmentally relevant oestrogen concentrations using different extraction conditions. The least expensive and time-consuming method QuEChERS provided the best extraction recoveries (53–84%) from all techniques. MAE achieved the highest recovery from conventional techniques for less polar oestrogens using dichloromethane: acetone 3:1 mixture as an extraction solvent (50–71%), but for extraction of the whole group of oestrogens including more polar estriol acetone or methanol must be used. ASE provided higher extraction recoveries using dichloromethane at 60°C (53–74%) for less polar oestrogens. However, the repeatability of results was unsatisfactory and recoveries using other extraction conditions were lower than for MAE. The most time-consuming SWE achieved the worst extraction recoveries and for isolation of low oestrogen concentrations from sediments, it is completely unsuitable.     

Molecularly imprinted polymers for the clean-up of a basic drug from environmental and biological samples

A molecularly imprinted polymer (MIP) was synthesized and evaluated to selectively extract an alpha-blocker, i.e. alfuzosin, from human plasma. The synthesis of the MIP was performed in dichloromethane with methacrylic acid as monomer and the target drug as template. A first series of experiments was carried out in dichloromethane to estimate the potential of the MIP in its specific recognition medium, i.e. dichloromethane, by developing a selective procedure and by measuring the capacity of the sorbent. An optimized procedure was developed for the selective extraction of alfuzosin with a recovery close to 100% in this medium and a specific capacity of 1.3 micromol g(-1) of MIP was measured. A study in aqueous media was also carried out by a comprehensive approach of the retention mechanism in order to build a selective procedure of extraction. The effects of the amount and of the charge of cations were studied and an optimal pH value was defined to limit matrix effects. Then, the alfuzosin MIP was then directly used to selectively extract the target drug from human plasma with an extraction recovery of 60%. Lastly, a soil was extracted by a pressurized solvent and the resulting extract was cleaned up on the MIP, showing the possibility to use this selective sorbent for the sample treatment of various complex matrices.     

Analysis of Cembranoids in Flue‐cured Tobacco by Accelerated Solvent Extraction and Gas Chromatography‐Mass Spectrometry‐Selected Ion Monitoring

An efficient and sensitive analytical method based on accelerated solvent extraction (ASE) and gas chromatography‐mass spectrometry‐selected ion monitoring (GC‐MS‐SIM) was developed and validated for analysis of cembranoids in flue‐cured tobacco leaves. Extraction efficiency of different pretreatment methods including liquid‐solid extraction (LSE), ultrasound‐assisted extraction (UAE), Soxlet extraction and accelerated solvent extraction (ASE) was compared and ASE was chosen as the optimal extraction method. During ASE procedure, effect of four parameters on extraction efficiency was considered and the experimental conditions were selected as follows: extraction solvent: dichloromethane; oven temperature: 50 °C; static time: 5 min and number of cycles: 2. Working standards of cembranoids were isolated by silica gel column chromatography and the identification was performed by mass spectrometry. Performance characteristics such as linearity, limit of detection (LOD), limit of quantitation (LOQ), precision and recovery were studied. The LOD and LOQ values were ranging from 5.0 × 10^?3 to 6.9 × 10^?3 μg/mL and 1.7 × 10^?2 to 2.3 × 10^?2 μg/mL for all analytes. At three different spiked levels, recoveries for CBT‐ol, α‐CBT‐diol and β‐CBT‐diol were 94.6%‐105.1%, 93.0%‐97.2% and 88.7%‐107.5% while the relative standard deviations (RSDs) were in the ranges of 3.9%‐6.2%, 1.8%‐8.7% and 1.7%‐6.0%, respectively. The proposed analytical methodology was successfully applied in the analysis of cembranoids in tobacco samples.     

Optimization of extraction and quantification technique for phenolics content of garlic (Allium sativum): An application for comparative phytochemical evaluation based on cultivar origin

A range of conventional, i.e. maceration, percolation, ultrasonic assisted, Soxhlet and Soxtec extraction (STE), to advanced extraction techniques of accelerated solvent extraction (ASE) was utilized for the first time in order to optimize the extract yield and recovery of phenolics—gallic acid (GA), rutin (RT) and quercetin (QT)—quantified via ultra-high performance liquid chromatography with diode array detector (UHPLC–DAD). The effect of solvents (n-hexane, dichloromethane and methanol) and temperature (60, 80 and 100°C) upon extraction yield, phenolic content and antioxidant activity (DPPH, ABTS and DPPH) was studied, and the method was validated in commercial food samples from Saudi Arabia, China and India. A high extract yield with percentage recovery was observed for STE (1221.10 mg/5 g; 24.42%) and ASE techniques (91.50 mg/1 g; 9.15%) in methanol at 100°C. UHPLC–DAD showed retention times (min) of 0.67, 1.93 and 1.90 for GA, RT and QT, respectively in the shortest runtime of 3 min. The yield for phenolics was higher for STE/ASE (ppm): 15.27/15.29 (GA), 85.24/37.56 (RT) and 52.20/33.40 (QT), respectively. In terms of antioxidant activities, low IC₅₀ values (μg/ml) of 1.09/1.18 (DPPH), 2.11/5.32 (ABTS) and 4.35/7.88 (phenazine methosulfate–nicotinamide adenine dinucleotide) were observed for STE and ASE, respectively. Multivariate analysis for STE showed a significant (P = 0.000) correlation for extraction type vs. extract yield and phenolics content; however, there was no significance for antioxidant activities vs. extraction type. ASE showed a positive correlation for solvent vs. extraction yield, phenolics and antioxidant activity; however, there was no correlation for extraction yield and DPPH activity. Principal component analysis for STE showed a major variability (52.02%) for extraction yield and phenolics in PC1 followed by PC2 (38.30%) for antioxidant activities. For ASE, PC1 (48.68%) showed a positive correlation for solvent vs. extraction yield and phenolics while PC2 (33.12%) showed a positive correlation for temperature and antioxidant activities. STE and ASE were the optimized extraction techniques for the garlic food sample while a significant effect of solvent and temperature was observed upon extraction yield, phenolics and antioxidant activity.     

Influence of extraction methodologies on the analysis of five major volatile aromatic compounds of citronella grass (Cymbopogon nardus) and lemongrass (Cymbopogon citratus) grown in Thailand

This paper deals with the systematic comparison of extraction of major volatile aromatic compounds (VACs) of citronella grass and lemongrass by classical microhydrodistillation (MHD), as well as modern accelerated solvent extraction (ASE). Sixteen VACs were identified by GC/MS. GC-flame ionization detection was used for the quantification of five VACs (citronellal, citronellol, geraniol, citral, and eugenol) to compare the extraction efficiency of the two different methods. Linear range, LOD, and LOQ were calculated for the five VACs. Intraday and interday precisions for the analysis of VACs were determined for each sample. The extraction recovery, as calculated by a spiking experiment with known standards of VACs, by ASE and MHD ranged from 64.9 to 91.2% and 74.3 to 95.2%, respectively. The extraction efficiency of the VACs was compared for three solvents of varying polarities (hexane, dichloromethane, and methanol), seven different temperatures (ranging from 40 to 160 degrees C, with a gradual increment of 20 degrees C), five time periods (from 1 to 10 min), and three cycles (1, 2, and 3 repeated extractions). Optimum extraction yields of VACs were obtained when extractions were carried out for 7 min with dichloromethane and two extraction cycles at 120 degrees C. The results showed that the ASE technique is more efficient than MHD, as it results in improved yields and significant reduction in extraction time with automated extraction capabilities.     

Efficiency of Different Methods and Solvents for the Extraction of Polycyclic Aromatic Hydrocarbons from Soils

The efficiencies of supercritical fluid extraction (SFE), accelerated solvent extraction (ASE), Soxhlet, and ultrasonic extraction in the analysis of polycyclic aromatic hydrocarbons (PAHs) in soils were evaluated. Solvents with different polarity were used to extract the PAHs from two soils, one with high and one with low contamination level. ASE showed good results with all solvents almost independent of the solvent polarity and the best results with acetone-toluene (1 : 1). Ultrasonic extraction with acetone-toluene for the uncontaminated soil and acetone-ethanolamine for the highly contaminated also showed good recoveries. The time-consuming Soxhlet extraction with pentane or dichloromethane was less effective. The PAH recovery from SFE was related to the soil matrix or the contamination level. The best extraction conditions (CO 2 /10% pentane) are successful for the soil with a low contamination level and a high humic acid content whereas the extractions of the highly contaminated soil gave poor results irrespective of the solvent used.     

加速溶剂萃取技术在中药有效成分分析中的应用

以两种药材为研究实例,对加速溶剂萃取法（ASE）在中药材有效成分提取研究中的应用进行了简要介绍。采用正交试验法考察了提取丹参中丹酚酸B的提取条件（萃取温度、静态萃取时间、萃取溶剂以及料液比）,确定了较好的实验条件。比较了ASE、水蒸气蒸馏法、超声波提取法及索氏提取法对木香挥发油的提取效果,结果表明ASE对木香挥发油的提取效果最好。     

加速溶剂萃取-气相色谱-负化学源质谱法测定茶叶中有机氯和拟除虫菊酯类农药残留量

建立了茶叶中13种有机氯和10种拟除虫菊酯农药残留量的气相色谱-负化学离子源.质谱(GC-NCl-MS)分析方法.茶叶样品用V(丙酮):V(CH2Cl2)=1:1混合液作提取剂经加速溶剂萃取,提取液经凝胶色谱净化除去大部分的色素、脂类和蜡质,再经活性炭-氨基(Carb-NH2)复合小柱和Florisil小柱净化后,用GC-NCl-MS的选择离子监测方式(SIM)进行定性和定量分析.添加50μg/kg 浓度水平时,农药回收率在45.6%～112.4%之间,相对标准偏差在0.57%～10.1%之间;方法的检出限(3倍信噪比)在0.05～10.0μg/kg之间.方法适用于出口茶叶农残检测实际工作.     

快速溶剂萃取-气相色谱-三重四极杆质谱法测定沉积物中的酞酸酯

建立了快速溶剂萃取(ASE)-气相色谱-三重四极杆质谱(GC-MS/MS)测定沉积物中酞酸酯的方法。样品用二氯甲烷-丙酮(体积比为1:1)混合溶剂在100 ℃、103.4 MPa (1500 psi)条件下经快速溶剂萃取、以5 mL/min的速率经凝胶渗透色谱(GPC)净化去除大分子干扰物后,采用GC-MS/MS分析测定。采用内标法定量,17种酞酸酯的检出限为0.05～0.40 μg/kg;回收率为50.5%～107.9%,相对标准偏差为3.5%～13.9%。采用替代物基体加入法对方法的性能进行了验证,3种替代物的回收率为65.3%～95.8%。该方法快速、灵敏度高,能同时准确定性定量测定17种酞酸酯。     

ASE-HPLC检测某型号球形发射药中的叠氮硝胺、硝化甘油、Ⅱ号中定剂含量的研究

采用快速溶剂萃取（ASE）技术和高效液相色谱法测定某球形药中叠氮硝胺（DIANP）、硝化甘油（NG）和Ⅱ号中定剂（C2）的含量．ASE提取条件：二氯甲烷做萃取溶剂,萃取温度100℃,静态萃取10min,萃取2次．HPLC测定条件：YWGC18柱（150×4．6mm,10μm）,以甲醇和水作为流动相,梯度洗脱,流速1 mL／min,检测波长210nm．测定结果表明DIANP、NG、C2平均回收率分别为99．6％、100．3％、99．4％,RSD分别为0．7％、0．8％、0．9％（n=5）,检出限分别为2.1、1.5和0．2mg／L,线性范围分别为0．02～0．98g／L,0．03～1．38g／L,0．002～0．124g／L．用此方法共检测某批球形发射药样品5份,检测结果与滴析-HPLC法检测结果相当．