离子阱串联质谱法测定土壤及沉积物中的有机氯农药与多氯联苯

建立了加速溶剂提取、固相萃取净化、气相色谱-离子阱串联质谱法测定土壤和沉积物中25种有机氯农药和多氯联苯单体的分析方法.六六六、滴滴涕等17种有机氯农药(OCPs)的方法检出限(MDL)为0.049～0.274μg/kg,除异狄氏剂(线性范围为3.45～441.6μg/L)外,其余16种OCPs的线性范围均为1.73～...     

凝胶渗透色谱净化-气相色谱/串联质谱分析蘑菇中的36种农药残留

建立了用凝胶渗透色谱净化-气相色谱/串联质谱分析蘑菇中36种农药残留的方法。蘑菇中的待测农药组分在30 ℃条件下用乙酸乙酯提取,高速匀浆后通过凝胶渗透色谱净化;选用填料为中性多孔的聚苯乙烯二乙烯基苯微球体的S-X3玻璃柱(22 g,19 cm×2 cm)作为凝胶渗透色谱净化柱,流动相为乙酸乙酯-环己烷(体积比为1∶1)溶液,流速5 mL/min;收集第7~15 min流出的液体用气相色谱-三重四极杆串联质谱仪测定。在0.01~1.0 mg/L的质量浓度范围内,各种农药标准溶液的线性相关系数均大于0.99。在样品中添加36种农药(添加水平为0.01,0.05,0.10 mg/kg)的混合标准溶液,平均回收率为72.6%~117.1%,相对标准偏差为2.0%~10.8%(n=5),最低检出限为 0.1~0.7 μg/kg,最低定量限为 0.2~2 μg/kg。     

搅拌棒吸附子萃取与GC-MS法测定水中20种有机氯农药

建立了搅拌棒吸附子萃取/气相色谱-质谱法(SBSE/GC-MS)同时检测水中α-六六六、γ-六六六、β-六六六、七氯、δ-六六六、艾氏剂、环氧七氯、γ-氯丹、顺-氯丹、硫丹Ⅰ、p,p-滴滴伊、狄氏剂、异狄氏剂、p,p-滴滴滴、硫丹Ⅱ、p,p-滴滴涕、异狄氏剂醛、硫丹硫酸盐、甲氧滴滴涕、异狄氏剂酮20种有机氯农药含量的方法.样品在室温下经拌棒吸附子搅拌吸附,甲醇解吸附后,以J&W DB-35 MS(30 m×0.25 mm×0.25 μm)石英毛细管色谱柱为分析柱,气相色谱-质谱选择离子流模式检测.考察了萃取时间、氯化钠及甲醇加入量等对萃取的影响.实验结果表明:在2.5 ～20.0 μg/L 范围内,20种有机氯农药呈良好的线性关系,检出限(S/N=3)为0.008 ～0.118 μg/L,水样中分别添加2.5、20 μg/L的20种有机氯农药,回收率为 52% ～117%,相对标准偏差小于13%(n= 6).该方法操作简便、快速、灵敏度高,应用于实际样品检测,结果满意.     

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。     

加速溶剂萃取-气相色谱/串联质谱法测定土壤中20种有机氯农药

建立了用加速溶剂萃取法(ASE)提取、凝胶渗透色谱(GPC)净化、三重四级杆气相色谱串联质谱法(多反应监测模式,MRM)同时测定土壤中20种有机氯农药的方法。考察了不同分段时间对目标物净化效率及回收率的影响,并以消除背景干扰、提高测定灵敏度为目的,优化了串联质谱的仪器参数,确定了测定方法。当取10 g土壤时,20种有机氯农药的方法定量限在0.48~1.96μg/kg之间,实际土壤样品的加标回收率在73.7%~118%之间,相对标准偏差在2.7%~13%之间。对5份不同类型土壤进行检测。     

坚果中185种农药残留的气相色谱-串联质谱法测定

建立了花生仁、葵花籽、核桃仁和杏仁中185种农药多残留的气相色谱-串联质谱(GC-MS/MS)检测方法.样品经乙腈(含1%乙酸)均质提取,EN\1-18串联PSA固相萃取柱净化,在多重反应监测(MRM)模式下进行气相色谱-串联质谱法测定.185种农药在坚果样品中的检出限(S/N=5)为0.02～526.4μg/kg,定...     

固相萃取净化-气相色谱/串联质谱法测定叶中54种农药残留量

建立了固相萃取净化-气相色谱/串联质谱( SPE-GC-MS/MS)分析茶叶中54种农药残留的方法.样品用乙睛提取,提取液经石墨化炭黑/氨基固相萃取柱净化后,采用气相色谱-串联质谱方法在分时段选择反应监测模式下进行测定,外标法定量.当54种农药加标水平为10、50、100 μg/kg时,回收率为60％～150％,方法的...     

同位素稀释高分辨气相色谱-高分辨质谱法测定土壤中痕量有机氯农药残留

建立了同位素稀释高分辨气相色谱-高分辨质谱测定土壤中痕量有机氯农药残留的分析方法。采用加速溶剂法萃取土壤样品,以正己烷/丙酮(体积比为1:1)为提取溶剂,提取液经过Florisil硅土固相萃取小柱净化后,采用高分辨DB-5MS毛细管色谱柱(30 m×0.25 mm×0.25 μm)分离,以保留时间和同位素特征离子丰度比定性,同位素峰面积比定量。实验结果表明,方法的回收率为77.3%～114.5%,相对标准偏差(RSD)≤10.81%（n=5）,检出限均小于0.04 pg/g。应用该方法检测某地区表层土壤中的有机氯农药,结果表明该方法适合测定环境土壤背景中痕量有机氯残留。     

冷冻去脂-固相萃取/气相色谱-质谱法对水产品中禾草丹、溴氰菊酯及19种有机氯农药残留的测定

建立了气相色谱-质谱快速测定水产品中禾草丹、溴氰菊酯及19种有机氯农药残留的方法.样品经乙腈提取后采用冷冻法去除提取溶液中的大量脂肪,再经氨基固相萃取柱进一步净化后用GC-MS测定.21种农药在0.1～2.0 mg/L范围内线性良好,相关系数r＞0.999,样品添加量为0.02～0.1 mg/kg时回收率为79%～114%,相对标准偏差不大于13.5%,检出限为0.5～20 μg/kg(S/N＝3).     

蔬菜中26种农药残留的高效液相色谱-串联质谱法测定

建立了蔬菜中26种农药的反相高效液相色谱-电喷雾串联质谱 (LC-ESI MS/MS) 检测方法.蔬菜样品经含0.1%醋酸的乙腈提取、浓缩、分散型固相萃取净化,液相色谱串联质谱测定,内标法定量.26种农药在5.0 ～200 μg/L范围内线性关系良好(r2＞0.997).在豌豆、菠菜、脱水葱3种基质中的检出限和定量下限均为2.0 μg/kg和5.0 μg/kg.在5.0、10.0、40.0 μg/kg 3个添加水平下,26种农药的回收率为70% ～110%,精密度(RSD)小于15%.方法准确、灵敏、简单,适用于蔬菜中26种农药残留的同时测定.     

微波萃取气相色谱法测定淀粉中14种有机氯农药残留

建立了淀粉中14种有机氯农药:六六六及滴滴涕的4种异构体、五氯硝基苯、四氯硝基苯、四氯苯胺、五氯苯胺、腐霉利、甲基五氯苯基硫醚(MPCPS)的微波辅助和气相色谱分析方法.优化了气相色谱检测条件,考察了提取方法、萃取条件、净化条件对提取效果的影响.目标农药在20～200 μg/kg范围内线性良好,平均回收率在68%～10...     

Hydrophobic vitamin B12. Part 19: electroorganic reaction of DDT mediated by hydrophobic vitamin B12

The controlled-potential electrolysis of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) was carried out at -1.4 V vs. Ag-AgCl in the presence of a hydrophobic vitamin B12, heptamethyl cobyrinate perchlorate. DDT was dechlorinated to form 1,1-bis(4-chlorophenyl)-2,2-dichloroethane (DDD), 1,1-bis(4-chlorophenyl)-2,2-dichloroethylene (DDE), 1-chloro-2,2-bis(4-chlorophenyl)ethylene (DDMU) and 1,1,4,4-tetrakis(4-chlorophenyl)-2,3-dichloro-2-butene (TTDB)(E/Z), and quantitative recovery of the catalyst after the electrolysis was confirmed by electronic spectroscopy. A photo-sensitive intermediate having a cobalt-carbon bond formed during the electrolysis was characterized by electronic spectroscopy. A mechanism for the formation of various dechlorinated products was investigated by using deuterium solvents and various spectroscopic measurements such as UV-VIS and the EPR spin-trapping technique.     

分散液液微萃取/气相色谱-质谱法测定蜂蜜中六六六和滴滴涕类农药残留

建立了分散液液微萃取(DLLME)与气相色谱-质谱法(GC-MS)联用快速检测蜂蜜中六六六(BHC)和滴滴涕(DDT)类农药残留的分析方法.使用三氯甲烷为萃取剂,通过涡旋、离心使分析物富集到微量三氯甲烷中,采用气相色谱-质谱进行分析.实验对影响DLLME萃取效率的因素,如萃取剂种类和体积、分散剂种类和体积、萃取时间等进行了考察,同时对方法的基质效应和性能进行了评估.结果显示:由于基质效应,8种六六六和滴滴涕类农药都出现信号增强现象.8种六六六和滴滴涕类农药在2~500 μg/L范围内线性关系良好,相关系数(r²)为0.991~0.998,方法富集倍数为74~96;当试样的加标水平为20、50和100 μg/kg时,8种六六六和滴滴涕类农药的回收率为61.0%~100.1%,相对标准偏差(RSD, n=5)为2.2%~19.5%.8种六六六和滴滴涕类农药的最低检测浓度均为20 μg/kg,最小检出量皆为1.0 ng.该方法简单、快速、高效,适用于蜂蜜中六六六和滴滴涕类农药的残留检测.     

Electronic structure and biological activity of chosen DDT-type insecticides studied by 35Cl-NQR

A correlation between the electronic structure and biological activity of chosen dichlorodiphenyltrichloroethane (DDT)-type insecticides: 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane, 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane, 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene, 2,2-bis(4-chlorophenyl)ethanoic acid and 4,4'-dichlorobenzophenone (used in agriculture) has been analysed on the basis of the (35)Cl-nuclear quadrupole resonance (NQR) spectroscopy. The (35)Cl-NQR resonance frequencies measured at 77 K have been correlated with the lethal dose (LD(50)) parameter that characterises the biological activity of these insecticides.     

加速溶剂萃取-在线凝胶渗透色谱-气相色谱-质谱联用法快速测定蔬菜和水果中多农药残留

建立了加速溶剂萃取-在线凝胶渗透色谱-气相色谱-质谱联用(GPC-GC-MS)快速测定蔬菜、水果中代表性农药残留的检测方法。样品经二氯甲烷-丙酮(1:1, v/v)加速溶剂提取,活性炭柱-氨基柱串联净化,氮吹至干,残留物用环己烷-丙酮(7:3, v/v)溶解后经GPC-GC-MS系统以选择离子监测(SIM)模式测定。结果表明,22种农药在各自的线性范围内线性关系良好(相关系数不低于0.9981),检出限(以信噪比(S/N)为3计算)为0.3～1.8 μg/kg,定量限（S/N=10）为1~6 μg/kg。在2种基质(大白菜、苹果)中3个添加水平下的回收率为70.5%～107.5%,相对标准偏差为2.1%～8.7%。该方法提取效率高,定性定量准确、灵敏,可实现对蔬菜、水果中多农药残留的快速检测。     

Mixed liquids for single-drop microextraction of organochlorine pesticides in vegetables

A new approach for the extraction of nine kinds of organochlorine pesticides (OCPs) from vegetable samples coupling single-drop microextraction with gas chromatography-mass spectrometry was presented. Experimental parameters, such as organic solvent, exposure time, agitation and organic drop volume were controlled and optimized. An effective extraction was achieved by suspending a 1.00microL mixed drop of p-xylene and acetone (8:2, v/v) to the tip of a microsyringe immersed in a 2mL donor aqueous solution and stirred at 400rpm. The approach was applied to the determination of OCPs in vegetable samples with a linearity range of 0.05-20ng mL(-1) for alpha-, beta-, gamma-, delta-hexachlorobenzene (BHC) and dicofol, 0.5-20ng mL(-1) for dieldrin and 2,2-bis(4-chlorophenyl)-1,1-dichloroethane (DDD) or 0.5-50ng mL(-1) for 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE) and 2-(2-chlorophenyl)-2 (4-chlorophenyl)-1,1,1-trichloroethane (p,p'-DDT). Correspondingly, the determination limit at an S/N of 3 ranged from 0.05ng mL(-1) for alpha-, beta-, gamma-, delta-BHC to 0.2ng mL(-1) for dicofol, dieldrin or p,p'-DDT. The relative recoveries were from 63.3 to 100%, with repeatability ranging from 8.74 to 18.9% (relative standard deviation, R.S.D.). The single-drop microextraction was proved to be a fast and simple approach for the pre-concentration of organochlorine pesticides in vegetable samples.     

Investigation of the feasibility of TiO(2) nanotubes for the enrichment of DDT and its metabolites at trace levels in environmental water samples

TiO(2) nanotubes, novel nanomaterials synthesized from hydrothermal treatment, were investigated for being used as a new solid-phase extraction adsorbent with o,p'-DDT, [1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane, p,p'-DDT, [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane] and its principle metabolites p,p'-DDD, [1,1-dichloro-2,2-bis(4-chlorophenyl)ethane] and p,p'-DDE [1,1-(2,2-dichloro-ethanylidene)-bis(4-chlorobenzene)] as the target analytes. Several factors such as eluant and its volume, the sample pH, sample volume and the flow rate of samples, were optimized. The effect of humic acid, which is often present in natural water system, was also investigated. Under the optimal conditions, lower detection limits of 0.0031, 0.0037, 0.0053 and 0.0025 ng mL(-1) for p,p'-DDD, p,p'-DDT, o,p'-DDT and p,p'-DDE, respectively, were obtained. The proposed method was successfully applied to the analysis of the target compounds in several environmental water samples. Good recoveries over the range of 81.2-115% were obtained. These results indicated that titanium nanotubes had enormous potential in environmental field as a novel SPE adsorbent material.     

高效液相色谱-串联质谱法测定蜂蜜中9种农药残留

建立了同时测定蜂蜜中9种苯并咪唑类和新烟碱类农药的全自动固相萃取-高效液相色谱-串联质谱检测方法。蜂蜜样品用磷酸盐缓冲液（pH=7.8）溶解，超声提取，经亲水亲脂平衡（hydrophilic-lipophilic balance，HLB）固相萃取小柱净化，氮吹浓缩，定容，过滤膜后进行高效液相色谱-串联质谱分析，采用多反应监测（MRM）模式测定，以内标法定量。结果表明，在0.002~0.05 mg/L范围内9种农药呈现出较好的线性关系（相关系数r² ≥ 0.99），检出限和定量限分别为0.1~1.0 μg/kg和0.3~2.0 μg/kg。对阴性蜂蜜，在5.0、10.0、20.0 μg/kg 3个水平下分别进行加标回收试验，测出9种农药的平均回收率在78.2%~101.2%之间，相对标准偏差为1.3%~14.3%（n=6）。该方法可适用于大批量蜂蜜样品的快速准确测定。     

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。     

鸡肉中11种喹诺酮类药物多残留的高效液相色谱检测

建立了用荧光检测器同时测定11种喹诺酮类药物(包括诺氟沙星、培氟沙星、环丙沙星、恩诺沙星、氧氟沙星、达氟沙星、洛美沙星、二氟沙星、沙拉沙星、恶喹酸和氟甲喹)在鸡肉中的多残留的高效液相色谱检测方法。鸡肉样品用10%三氯乙酸-乙腈(体积比为7∶3)提取两次并稀释,随后用反相固相萃取柱净化。采用Hypersil BDS-C18色谱柱分离,以乙腈和水为流动相梯度洗脱,荧光检测器用程序编程检测波长检测。11种喹诺酮类药物标准曲线的线性范围为5～1200 μg/L,相关系数大于0.998。在高、中、低三个添加水平下的回收率为56%～119%,批内相对标准偏差为0.4%～16.1%,批间相对标准偏差为1.4%～23.0%。检出限和定量限分别为1～23 μg/kg和4～40 μg/kg。该方法快速、灵敏,达到了兽药残留检测的要求。