超高压液相色谱-串联质谱法测定含硫蔬菜中烟碱类农药残留

[目的]为快速准确测定复杂基质样品中烟碱类农药残留,建立了含硫蔬菜中烯啶虫胺等烟碱类农药多残留的液相色谱-电喷雾串联质谱测定方法.[方法]样品经乙腈提取,用PSA、C18填料净化后,以BEH C18超高效液相色谱柱,以电喷雾离子源正离子多反应监测模式下进行测定.[结果]烯啶虫胺等7种农药在10-500 μg/L的范围内均成线性,回收率范围在70%～120%之间,方法的检出限在0.2～2.5 μg/kg之间.[结论]方法具有操作简便、重现性好和灵敏度高的特点,可满足含硫蔬菜中烟碱类农药残留限量检测的需要.     

超高效液相色谱-串联质谱法测定枸杞中常见的5种农药残留

建立超高效液相色谱-串联质谱法(UPLC-MS/MS)测定枸杞中吡虫啉、甲基硫菌灵、啶虫脒、多菌灵、嘧菌酯5种农药残留量。样品经乙腈提取,C18固相萃取小柱净化,以甲醇+0.1%甲酸水溶液为流动相,采用梯度洗脱在ACQUITY UPLC BEH C18柱上分离。结果表明,在添加水平为0.001~0.1 mg/kg时,吡虫啉、甲基硫菌灵、啶虫脒、多菌灵、嘧菌酯的回收率在82.15%~102.81%之间,相对标准偏差为1.89%~5.02%,符合农药残留分析要求。     

加速溶剂萃取-气相色谱-三重四极杆串联质谱法测定芸豆中的18种农药残留

[目的]建立测定芸豆中18种农药残留量气相色谱-三重四极杆串联质谱(GC-MS/MS)的检测方法,对贵州芸豆主产地104个样品进行分析检测。[方法]通过考察不同提取溶剂、基质效应、净化方法等3因素进行系统优化,建立了芸豆农药残留分析最优检测方法,基质内标法定量。[结果]在质量浓度为0.05～1.00 mg/L范围内,18种农药的线性关系良好,线性回归方程的相关系数(R~2)均大于0.996,方法检出限为0.0011～0.0231 mg/kg。分别向阴性芸豆样品中添加18种农药标准品质量分数为0.05、0.2、0.6 mg/kg的3个水平,其加标平均回收率为79.54%～101.11%,相对标准偏差RSD为1.02%～8.45%。[结论]与其他农药残留检测方法比,该方法具有前处理操作简单、净化效果好、重复性好、灵敏度高等优势,适用于芸豆中18种农药残留量的测定。对104份芸豆样品进行18种农药残留分析检测,检测呈阳性农药均未超过相关规定的农药最大残留限量值。     

固相萃取GC-MS测定水中16种农药的研究

文章将C18和Sep-pak Porapak Rox固相萃取小柱活化后联用富集水中16种农药,用乙酸乙酯洗脱,浓缩这16种农药,确定各农药的保留时间和定量离子,用气相色谱/质谱联用仪(GC/MS)选择离子模式进行分析测定,分析了各农药的工作曲线线性、回收率和精密度。结果表明,各农药的工作曲线线性、回收率和精密度较好,线性相关系数在0.994～0.999之间,回收率在68.9%～109.2%之间,相对标准偏差小于7.6%。     

固相萃取-高效液相色谱法测定水中6种氨基甲酸酯类农药残留量

建立了水中6种氢基甲酸酯类农药的残留量液相色谱分析方法,样品经C18小柱净化,乙腈-水为流动相,紫外检测器检测,外标法定量.结果表明:方法在0.05～2 mg/L范围内线性关系较好,相关系数为0.9992～0.9999.在添加0.5～1.0 mg/L的水平内,6种氨基甲酸酯类农药平均回收率在70.55%～104.76%之间,相对标准偏差在0.21%～3.29%之间,方法检出限在0.015～0.071mg/L之间.该方法检出限、回收率和精密度都能达到农残分析的要求.     

高效液相色谱法同时测定多种杀虫剂的有效成分

建立了用高效液相色谱法测定农药市场上常见的8种杀虫剂及2种禁限用农药有效成分的分析方法。采用C18柱(150L×4.6mm),以乙腈-水为流动相,紫外检测器检测,外标法定量。结果表明,样品的加标回收率为90.0%¹02.0%,相对标准偏差为0.01%102.0%,相对标准偏差为0.01%¹.47%。该方法简单、快速、结果准确,可作为单剂、复配制剂同时测定其有效成分的方法。     

高效液相色谱-串联质谱法同时检测蔬菜、水果中21种农药多残留

建立了以固相萃取/高效液相色谱-串联质谱(LC/MS/MS)同时测定蔬菜、水果中痕量21种农药残留量的方法.蔬菜、水果样品提取液经固相萃取后采用C18柱分离,以0.1%甲酸乙腈-0.1%甲酸水溶液为流动相,梯度洗脱,以保留时间和质荷比对分离出的组分予以定性确证,用峰面积进行定量.结果表明,21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,样品中最低检出质量分数为0.0005～0.003 mg/kg,样品的平均加标回收率为76.34%～119.33%.方法简便、快速、灵敏,适用于蔬菜、水果中这些农药的同时分析.     

一种快速测定禽蛋中多种有机氯农药残留的方法

采用改良Qu ECh ERS法来提取禽蛋中的有机氯农药残留。样品经乙腈提取,用C18、NH2、石墨炭黑固体分散材料来净化,GC-ECD法检测。结果表明,该方法的检出限基本能达到GB/T 5009.19-2008和GB/T 5009.162-2008方法中要求的检出限。21种有机氯农药加标回收率均在80%~120%的范围内,RSD均小于10%,完全可以满足禽蛋中多种有机氯农药检测的要求。实验所用有机溶剂较少,也无须过GPC和SPE柱,可以为大批量的禽蛋类检测提供一种简单,快捷,准确,可靠,低成本的方法。     

QuEChERS-高效液相色谱-串联质谱法测定蜜蜂及蜂产品中5种农药及氟虫腈代谢物残留

[目的]建立蜜蜂及蜂蜜和蜂花粉中氟虫腈、氟甲腈、氟虫腈硫醚、氟虫腈砜、灭幼脲、氟啶脲、氟铃脲、杀铃脲等5种农药及氟虫腈代谢物的QuEChERS-高效液相色谱-串联质谱分析方法(HPLC-MS/MS),并将该方法用于实际样品检测.[方法]样品中的农药残留用乙腈提取,盐析后用C18、PSA吸附剂净化,经C18色谱柱分离,在...     

液相色谱-高分辨质谱用于大米多农残的筛查及定量

使用液相色谱-串联高分辨质谱(LC-MS/MS)对大米样品中农药残留进行筛查分析,并对筛查出的农药进行定量分析。采用粉碎、乙腈提取和固相萃取(SPE)净化柱净化等手段对大米样品进行前处理,处理后的样品通过高分辨液相色谱质谱联用仪进行检测,使用农残筛查软件对所得数据进行农药残留的筛查,结果显示大米样品中共有5种农药残留。配制该5种农药的标准溶液,进行线性、回收率和精密度试验,均得到较好的结果,最终使用该方法对大米样品中5种农药进行定量分析。     

唑草酯及其三种主要酸性代谢物在谷物、饲料中残留分析方法研究

研究了唑草酯及其主要酸性代谢物在谷物和饲料中残留分析方法。样品以丙酮提取,唑草酯过Si-SPE小柱,用气相色谱的ECD检测;唑草酯的三种主要酸性代谢物过串联SPE柱(SCX小柱在C18小柱上面),气相色谱和质谱联用检测。唑草酯的最小检测量为0.01ng,三种主要酸性代谢物的最小检测量为0.005ng。用优化后的方法在谷物、饲料中分别进行添加回收实验,得到的唑草酯平均添加回收率:添加0.1mg/L时为79.4%,添加1.0mg/L时为81.3%。三种主要酸性代谢物的准确性、灵敏度均达到农药残留分析的要求。     

Separation and analysis of phospholipids in different foods with a light-scattering detector

A method for the separation of phospholipids (PL) from total lipids by solid-phase extraction (SPE) with reversephase C₈ cartridges is described. The method was validated with a standard mixture of PL and applied to natural food matrixes, such as egg, chicken meat, salami, and ripened cheese. The recovery of PL ranged between 93 and 99.7% and was evaluated by an organic phosphorus spectrophotometric determination. The egg powder PL fraction obtained by SPE contained about 20% (w/w) nonpolar PL material when 100–150 mg of lipids were loaded onto the cartridge. Higher percentages of nonphospholipid components (30–43%) were obtained when the amount of lipids loaded was below or above the 100–150 mg range. The purified PL fractions were analyzed by high-performance liquid chromatography (HPLC) with an evaporative light-scattering detector. Good HPLC performance was observed even with low-purity SPE fractions (43% nonphospholipid material).     

超临界流体萃取脱除人参中痕量有机氯农药

利用在线固相吸附柱收集,淋洗剂洗脱超临界流体萃取出的真实人参样品中的有机氯农残实验,确定最佳的吸附柱和淋洗剂。通过实验确定利用C18作吸附剂,用正己烷洗脱可取得最优效果。此外,还对直接冷凝收集法、索氏提取法与固相吸附柱收集法进行了对比。     

Effect of absorbent in solid‐phase extraction on quantification of phospholipids in palm‐pressed fiber

Palm‐pressed fiber (PPF) is a by‐product of palm oil milling and it has been found to contain a high percentage of phospholipids (PL). The aim of this work was to evaluate the best solid‐phase extraction (SPE) method to purify PL from PPF. The purified PL were analyzed using high‐performance liquid chromatography (HPLC) with an evaporative light‐scattering detector (ELSD). The oil was extracted from PPF using the Folch method and classes of PL were purified using SPE. Different solvent phases and normal‐phase SPE cartridges [silica (Si), aminopropyl‐bonded silica (NH₂) and diol‐bonded silica (2OH)] at the same ratio of oil to sorbent mass were used to study the separation of PL from the extracted oil. The recovery of each standard PL was performed in a model oil system with the same amount of standard PL being added, and the repeatability of the SPE method was investigated. The isolation of PL by SPE diol cartridge and subsequent analysis by HPLC/ELSD have shown to be an accurate and reproducible analytical method for the determination of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and lysophosphatidylcholine in PPF. This method provided a high yield and rapid separation of PL in PPF with less contamination from other lipid groups.     

Separation and purification of sulforaphane from broccoli by solid phase extraction

A simple solid-phase extraction (SPE) method for the determination of sulforaphane in broccoli has been developed. The optimal conditions were found to be use of a silica SPE cartridge, and ethyl acetate and dichloromethane as washing and eluting solvents, respectively, which could eliminate interferences originating from the broccoli matrix. The extracts were sufficiently clean to be directly injected into high-performance liquid chromatography (HPLC) for further chromatographic analysis. Good linearity was obtained from 0.05 to 200 μg/mL (r = 0.998) for sulforaphane with the relative standard deviations less than 3.6%. The mean recoveries of sulforaphane from broccoli were more than 90.8% and the detection limit (S/N = 3:1) was 0.02 μg/mL. The SPE method provides a higher yield of sulforaphane from crude extracts compared to conventional liquid-liquid extraction.     

固相萃取-气相色谱法测定水果、蔬菜中的氯丹

建立一种简单、灵敏的用于测定水果、蔬菜中氯丹残留量的气相色谱检测方法.样品用乙腈提取,经Florisil(弗罗里硅土)SPE小柱净化,由配有ECD检测器的气相色谱(GC-ECD)进行测定.该方法对水果、蔬菜中氯丹检出限为0.0002 mg/kg,工作曲线在0.001～0.08 μg/mL范围内呈良好的线性关系.在该线性范围内,苹果、柿子、西红柿和鲜笋中回收率为82.6％ ～93.1％.     

Determination of tylosin in milk samples by poly(ethylene terephthalate)-based molecularly imprinted polymer

Poly(ethylene terephthalate)-based molecularly imprinted polymers (MIPs) were synthesized, and their recognition capability was evaluated. Adsorption isotherm was described by the Langmuir model and the maximum adsorption capacity of MIP_Ty reached 172.4 mg g⁻¹ in water at pH 6.2. A recognition coefficient of 1.17 was obtained. A solid-phase extraction cartridge was manufactured and its behavior was evaluated for tylosin extraction from aqueous and milk samples. An off-line SPE-UV method was applied. An acceptable linearity was obtained in the range of 1–20 μg ml⁻¹ and the average recovery at three spike levels in milk samples was higher than 92%. The limit of quantification was 2.6 × 10⁻² μg ml⁻¹. The manufactured SPE cartridge has a great potential for clean-up processes in complex media. The cartridge offers a fast and sensitive option to the existing sorbents for extracting this drug from milk samples.     

气相色谱法测定青菜中有机磷农药残留量

采用气相色谱法测定青菜中10种有机磷农药残留量。样品用乙腈超声波提取,经弗罗里硅土固相小柱净化,以V二氧甲烷：V丙酮=9：1洗脱,GC—NPD检测,外标法定量。加标量为0．50μg／20g时,回收率在81．0％-111．3％,相对标准偏差在2．2％～6．6％。该方法适用性强,操作简便,色谱杂峰少。     

快速分离柱高效液相色谱法测定环境水样中多菌灵和噻菌灵的研究

研究并建立了用固相微萃取-快速分离柱高效液相色谱法测定环境水样中的多菌灵和噻菌灵的方法。样品中的多菌灵和噻菌灵用W aters Sep-pak C18反相固相萃取小柱预分离和富集,然后以ZORBAX Stab leBound(4.6 mm×50 mm,1.8μm)C18快速分离柱为固定相,甲醇-水(V(甲醇)/V(水)=1∶1)为流动相进行分离,流速为2.0 mL/m in;用二极管矩阵检测器检测,检测波长为286 nm,样品中的多菌灵和噻菌灵在2.0 m in内可达到基线分离。方法标准回收率为93%~104%,RSD为2.1%~3.2%。用新方法测定了环境水样中的多菌灵和噻菌灵,结果令人满意。     

垃圾焚烧炉飞灰中苯并[a]芘分析方法研究

用丙酮作溶剂超声波抽提垃圾焚烧炉飞灰中苯并[a]芘有机物,再用固相萃取纯化,然后利用配ODS3C18色谱柱的高效液相色谱仪,在以90%乙腈+10%水为流动相,流速为1mL/min,激发波长246nm和发射波长431nm的条件下测定了垃圾焚烧炉飞灰中的苯并[a]芘含量。结果表明:该方法检出限为0.01ng/mL,苯并[a]芘的回收率90.8%,方法的RSD(相对标准偏差)为3.89%。