高效液相色谱-质谱法测定水产品中孔雀石绿及其代谢物

在水产养殖过程中,人们经常使用各种药物进行水体消毒和防止鱼病害,孔雀石绿就是其中的一种染料类杀菌剂,近年来发现它特别是其代谢物在水产体内有明显的残留现象,且代谢物的残留时间较长,由于孔雀石绿化学官能团三苯甲烷是一种致癌物质,所以欧盟、美国等宣布禁止其在经济鱼类(观赏鱼除外)养殖过程中使用。经文献检索,国内虽有水产品中孔雀石绿残留量检验方法的报道,但未涉及代谢物残留量检测方法的报道。国外已建立的检测方法主要采用了气相色谱质谱联用法测定孔雀石绿代谢物、高效液相-色谱法同时测定孔雀石绿及其代谢物和高效液相色谱-质谱法同时测定孔雀石绿及其代谢物。我们利用HPLC-VIS和Q-TOFMS技术分别建立了高效液相色谱法(初筛法)和高效液相串联质谱法(确证法)两种检测方法。?更多还原     

高效液相色谱-串联质谱法测定沉积物中孔雀石绿及其代谢物

建立了沉积物中孔雀石绿及其代谢物(隐性孔雀石绿)的高效液相色谱-串联质谱检测方法.称取2 g沉积物样品,以乙腈和CH2Cl2超声萃取,旋转蒸发浓缩后,以30%甲醇定溶,经0.45μm滤膜过滤后,应用高效液相色谱-串联质谱测定沉积物中孔雀石绿及其代谢物残留量.本方法MG和LMG线性范围为0.5-100μg/L,相关系数为0.9982和0.9976,仪器检出限为0.2×10-9,定量限为0.5×10-9,MG回收率为44.5%～66.7%,LMG回收率31.4%～53.3%,方法检出限为2.0 ng/g.该方法适用于沉积物中痕量孔雀石绿及其代谢物的检测.     

超高效液相色谱-串联质谱法测定鱼粉中孔雀石绿

建立了鱼粉中孔雀石绿及其代谢物隐色孔雀石绿残留量的超高效液相色谱-串联质谱仪(UPLC-MS-MS)测定法。样品经乙腈提取,中性Al2O3固相小柱净化,超高效液相色谱C18柱分离,电喷雾正离子多反应模式(MRM)检测,内标法定量。方法的定量限为1.00μg/kg,线性范围为0.25～20.0μg/L。在1.00～20.0μg/kg的加标量下,孔雀石绿平均回收率范围为85.3%～104.4%,隐色孔雀石绿平均回收率范围为85.7%～101.4%,相对标准偏差均小于15%。方法适用于鱼粉样品中孔雀石绿残留的快速检测。     

超高效液相色谱-串联质谱法测定茶叶和土壤中丁醚脲及其代谢物的残留

建立了超高效液相色谱-串联质谱同时快速测定茶叶和土壤中丁醚脲及其代谢物残留量的方法.样品采用乙腈提取,加入乙酸铵和NaCl进行液液分配,PSA结合GCB进行同相分散萃取除杂质,Waters AcquityUPLC BEH C18柱(100 mm× 2.1 mm×1.7 μm)分离,超高效液相色谱-串联质谱法测定.在2....     

超高效液相色谱-串联质谱法同时测定水产调味品中的罗丹明B、结晶紫和孔雀石绿

1引言罗丹明B常被违法用于调味品的染色,孔雀石绿和结晶紫因具有消毒和杀菌作用而常被违法应用于水产品养殖中。三者结构类似,都具有高毒、高残留和致癌、致畸、致突变等特点,色谱分离较难,且由于食品基质复杂,对质谱检测影响较大。目前,单独检测3种物质的方法分别有高效液相色谱法[1]、气相色谱-质谱法[2]、液相色谱-质谱法[3]和液相色谱-     

液相色谱法同时测定水产品中孔雀石绿和结晶紫残留

用液相色谱-可见法同时测定水产品中孔雀石绿(MG)、结晶紫(CV)及其代谢物隐色孔雀石绿(LMG)和隐色结晶紫(LCV)的残留量,并用液相色谱-串联质谱法进行确证和定量。样品用乙腈提取,二氯甲烷液液分配,MCX阳离子固相萃取小柱净化,浓缩定容。以乙酸铵缓冲溶液和乙腈为流动相,经C18柱分离后,PbO2柱后衍生;用二极管阵列检测器在618nm测定孔雀石绿和隐色孔雀石绿,在588nm测定结晶紫和隐色结晶紫;并用串联质谱在电喷雾-多反应监测离子的模式下,进行质谱确证和定量;外标法定量,内标亮绿和氘代隐色孔雀石绿校正回收率。液相色谱-可见法的检出限为MG0.22,LMG0.28,CV0.22,LCV0.25μg/kg;液相色谱-串联质谱法的检出限为MG0.014,LMG0.018,CV0.014,LCV0.0084μg/kg。在2~20μg/kg范围内,回收率为75%~95%。     

固相萃取-高效液相色谱法测定蔬菜水果中的氨基甲酸酯杀虫剂及其代谢物残留

采用乙腈提取-固相萃取浓缩 高效液相色谱分离 柱后衍生-荧光检测法测定了蔬菜 水果中8种氨基甲酸酯类杀虫剂及其代谢物残留量。采用加标法(添加水平为0.10,0.50mg/kg)测定了氨基甲酸酯杀虫剂及其代谢物的回收率,其平均回收率为70%-120%,相对标准偏差(RSD)小于20%(n=3),最低检出限范围为0.0042-0.0106 mg/kg。该方法的测定结果满足多残留农残的检测要求。     

超高效液相色谱-串联质谱法测定水产品中孔雀石绿、结晶紫及其代谢物残留量

采用超高效液相色谱-串联质谱法同时检测水产品中孔雀石绿、结晶紫及其代谢物(隐色孔雀石绿、隐色结晶紫)。经匀浆处理的水产品样品,用乙腈提取,加入酸性氧化铝去除油脂,旋转蒸发器蒸干后,用甲酸-乙腈-水(0.1+10+89.9)溶液溶解,样品溶液用超高效液相色谱分离,电喷雾串联四极杆质谱进行检测。以氘代孔雀石绿、氘代隐色孔雀石绿为内标物。孔雀石绿、结晶紫及其代谢物的质量浓度均在5.0μg·L-1以内与其峰面积呈线性关系,检出限(3S/N)在0.10～0.12μg.kg-1之间。以空白水产品样品为基体进行回收试验,方法的回收率在90.2%～108.0%之间,相对标准偏差(n=6)在2.3%～7.6%之间。     

液相色谱-串联质谱法同时测定水产品中孔雀石绿、 结晶紫以及它们的隐色代谢物残留

采用液相色谱-串联质谱法(LC-MS/MS)同时测定水产品中的孔雀石绿、结晶紫以及它们的隐色代谢物残留。匀质后的水产品样品用乙腈和乙酸铵缓冲液提取。合并提取液,用二氯甲烷反提取,经中性氧化铝柱和PRS柱固相萃取净化。采用ZORBAX SB-C18色谱柱,并以0.5 mmol/L乙酸铵-乙腈(体积比为10∶90)混合溶液为流动相,无需使用氧化铅柱在线氧化,色谱分离后直接进入串联质谱检测器检测。采用电喷雾离子源,正离子多反应监测(MRM)模式检测。方法的检测限（S/N=3）可达0.5 ng/g,平均加标回收率为77.6%～98.1%,相对标准偏差均小于8.2%。大量实际水产品样品的检测结果表明,此方法适合于对水产品中孔雀石绿、结晶紫以及它们的隐色代谢物的残留检测。     

超高效液相色谱-串联质谱联用法对水产品中亚甲基蓝及其代谢物残留的检测

建立了超高效液相色谱-串联质谱同时检测水产品中亚甲基蓝及其代谢物天青A、天青B、天青C残留的方法.试样中的残留药物采用离子对试剂提取,正己烷脱脂净化,超高效液相色谱-串联质谱法测定.对前处理及液相色谱分离条件进行了探讨与优化.4种分析物在0.25 ～50 μg/L范围内线性关系良好,相关系数均大于0.999,方法定量下限可达0.5 μg/kg.在0.5、1.0、5.0 μg/kg范围内,平均加标回收率为80% ～91%;相对标准偏差为6.38% ～9.41%.方法灵敏、稳定,可满足水产品中亚甲基蓝及其代谢物残留的检测与确证及对药物动力学研究的需要.     

高效液相色谱法检测底泥中孔雀石绿及其代谢物

以乙腈、二氯甲烷、对甲苯磺酸和Mcilvain缓冲液等提取底泥中孔雀石绿和隐色孔雀石绿,以乙腈-甲醇-乙酸钠缓冲液为流动相,用DAD检测器在618nm处进行检测,建立了底泥中孔雀石绿及其代谢物的HPLC检测方法。孔雀石绿的回收率为75.2%~79.1%,隐色孔雀石绿的回收率为81.1%~84.2%,检测限均为5μg/kg。     

高效液相色谱法与酶免疫法快速测定鲫鱼中残留显/隐色孔雀石绿的比较

采用高效液相色谱(HPLC)法与酶免疫法(EIA)两种方法检测鲫鱼中残留显/隐色孔雀石绿的含量,对这两种分析方法所得的回收率进行了比较,当添加浓度在5.0～50.0 μg·kg-1时,其中 HPLC 法所测得的回收率为 68.2%～90.0%,相对标准偏差小于7.0%,检出限为 2 μg·kg-1;EIA 法所测得的回收率为 72.4%～92.3%,相对标准偏差小于 6.8%,检出限为1 μg·kg-1;两种方法均具有高效、快速、稳定的特点,能满足日常检验工作的需要.     

液相色谱法测定鳗鱼中的孔雀石绿

用高效液相色谱法测定鳗鱼组织中孔雀石绿的残留量。鱼体中残留的孔雀石绿在酸性介质下，经高速均质后，用乙腈均质提取，合并提取液，用二氯甲烷再次萃取，有机相过无水硫酸钠和氧化铝复合小柱后浓缩至干，用盐酸羟胺和流动相定容。以乙酸盐缓冲溶液和乙腈为流动相，在KR60－5氰柱上分离后，用可见光检测器在618nm处测定吸光强度，外标法定量。其检出限为1μg/kg，回收率为93.5%-99.6%，相对标准偏差RSD为6.54%-11.0%。     

反相高效液相色谱法测定水产品中孔雀石绿、结晶紫及其代谢物

利用反相高效液相色谱研究了水产品中孔雀石绿、结晶紫及其代谢物隐性孔雀石绿、隐性结晶紫的同时测定。采用Krom asil C18色谱柱,PbO2-硅藻土柱为柱后氧化柱,以乙腈-乙酸铵缓冲溶液-冰乙酸(体积比为58∶14∶28)体系为流动相。孔雀石绿、隐性孔雀石绿、结晶紫、隐性结晶紫的加标回收率分别为84.6%、85.8%、89.8%、88.5%,相对标准偏差分别为5.0%、4.7%、4.3%、4.6%(n=6),检出限为2μg/kg。     

高效液相色谱快速测定水产品中孔雀石绿、结晶紫及其无色产物的残留量

采用高效液相色谱同时检测水产品中孔雀石绿、结晶紫及无色孔雀石绿和无色结晶紫的残留量,样品经提取、净化处理后所得残渣用乙腈溶解后,通过采用C_(18)色谱柱,以乙腈(A)和pH3.0的0.02 mol·L~(-1)磷酸二氢钾缓冲溶液(B)按不同比例混合进行梯度淋洗,实现孔雀石绿、结晶紫及其代谢物的分离。用自制的二氧化铅柱氧化无色孔雀石绿及无色结晶紫。在588 nm波长处,测定4种物质的质量浓度在0.3～6.0 mg·L~(-1)范围内与其峰面积呈线性关系,相对标准偏差(n=6)小于2.5%,检出限(3S/N)小于1.9μg·kg~(-1),分析时间20 min。以凤尾鱼罐头为基体进行回收试验,方法的回收率在71.5%～88.6%范围。     

Studies on the synthesis and properties of malachite green imprinted polymer

A new molecularly imprinted polymer was synthesized with malachite green (MG) as molecular template, methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker, and azobisisobutyronitrile (AIBN) as initiator. Recognition properties of the MG imprinted polymer were studied by equilibrium adsorption and HPLC. The results showed that the imprinted polymer had good affinity and marked selectivity for MG, and can separate MG with its analogue commendably. The new polymer can be used for the enrichment of MG in complex sample, and can work as separation media to separate and detect MG by HPLC.     

Effect of Water Hardness on Catechin and Caffeine Content in Green Tea Infusions

The health benefits of green tea are associated with its high catechin content. In scientific studies, green tea is often prepared with deionized water. However, casual consumers will simply use their local tap water, which differs in alkalinity and mineral content depending on the region. To assess the effect of water hardness on catechin and caffeine content, green tea infusions were prepared with synthetic freshwater in five different hardness levels, a sodium bicarbonate solution, a mineral salt solution, and deionized water. HPLC analysis was performed with a superficially porous pentafluorophenyl column. As water hardness increased, total catechin yield decreased. This was mostly due to the autoxidation of epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Epicatechin (EC), epicatechin gallate (ECG), and caffeine showed greater chemical stability. Autoxidation was promoted by alkaline conditions and resulted in the browning of the green tea infusions. High levels of alkaline sodium bicarbonate found in hard water can render some tap waters unsuitable for green tea preparation.     

Simultaneous Determination of Norfloxacin and Tinidazole in Tablets by Reverse Phase High Performance Liquid Chromatography (RP - HPLC).

Abstract

A new simple, precise, rapid and selective HPLC-RP method has been developed for the simultaneous determination of Norfloxacin and Tinidazole in formulations, using 0.2 % Triethylamine (TEA) in water : Acetonitrile (80:20,v/v) and pH adjusted to 2.6 to 2.8 with Phosphoric acid, as a mobile phase, and C₁₈ SHODEX column (5 micron, 25 cm × 3.9 mm, ID) as stationary phase. Detection was carried out using a UV detector at 311 nm Linearity range and percentage recoveries for Norfloxacin and Tinidazole were 20 - 200 μg/mL and 30 - 300 μg/mL, 999.91 % and 99.94 % respectively.     

Production of malachite green oxalate and leucomalachite green reference materials certified for purity

Malachite green oxalate (MG oxalate) and leucomalachite green (LMG) have been prepared and certified as pure reference materials. The purities of MG oxalate and LMG were assessed by high-performance liquid chromatography–diode array detection (HPLC–DAD), nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), Karl Fischer titration, ashing and thermogravimetric analysis (TGA). MG oxalate was purified by supercritical fluid extraction (SFE). Prior to purification, commercial MG oxalate purity was estimated to be about 90%. The main impurities present in SFE-purified MG oxalate were identified and quantified using HPLC–DAD. The main impurities were found to be monode-MG (monodemethylated MG oxalate synthesis impurity), 4-(dimethylamino)benzophenone (4-DMABP), MG-carbinol and LMG. The homogeneity of both reference materials was also determined. Issues associated with the stability of LMG and MG oxalate in solution forced an extensive study investigating different parameters i.e. solvent, acid, analyte concentration and temperature. MG oxalate (100 μg/mL) was found to be stable in acetonitrile containing 1% v/v glacial acetic acid for at least 155 days and LMG (100 μg/mL) was stable in acetonitrile for at least 133 days. The final purity value for MG oxalate was 94.3 ± 1.4% m/m at the 95% confidence interval (or 67% m/m if MG cation is reported). For LMG, the certified purity was found to be 98.8 ± 0.8% m/m at the 95% confidence interval. Figure Calibration reference materials for malachite green and leucomalachite green, certified for purity, are essential in characterising these key analytes in a fish matrix reference material     

Decaffeination and Neuraminidase Inhibitory Activity of Arabica Green Coffee (Coffea arabica) Beans: Chlorogenic Acid as a Potential Bioactive Compound

Coffee has been studied for its health benefits, including prevention of several chronic diseases, such as type 2 diabetes mellitus, cancer, Parkinson’s, and liver diseases. Chlorogenic acid (CGA), an important component in coffee beans, was shown to possess antiviral activity against viruses. However, the presence of caffeine in coffee beans may also cause insomnia and stomach irritation, and increase heart rate and respiration rate. These unwanted effects may be reduced by decaffeination of green bean Arabica coffee (GBAC) by treatment with dichloromethane, followed by solid-phase extraction using methanol. In this study, the caffeine and chlorogenic acid (CGA) level in the coffee bean from three different areas in West Java, before and after decaffeination, was determined and validated using HPLC. The results showed that the levels of caffeine were reduced significantly, with an order as follows: Tasikmalaya (2.28% to 0.097% (97 ppm), Pangalengan (1.57% to 0.049% (495 ppm), and Garut (1.45% to 0.00002% (0.2 ppm). The CGA levels in the GBAC were also reduced as follows: Tasikmalaya (0.54% to 0.001% (118 ppm), Pangalengan (0.97% to 0.0047% (388 ppm)), and Garut (0.81% to 0.029% (282 ppm). The decaffeinated samples were then subjected to the H5N1 neuraminidase (NA) binding assay to determine its bioactivity as an anti-influenza agent. The results show that samples from Tasikmalaya, Pangalengan, and Garut possess NA inhibitory activity with IC₅₀ of 69.70, 75.23, and 55.74 μg/mL, respectively. The low level of caffeine with a higher level of CGA correlates with their higher levels of NA inhibitory, as shown in the Garut samples. Therefore, the level of caffeine and CGA influenced the level of NA inhibitory activity. This is supported by the validation of CGA-NA binding interaction via molecular docking and pharmacophore modeling; hence, CGA could potentially serve as a bioactive compound for neuraminidase activity in GBAC.