超声萃取-高效液相色谱法测定土壤中苯并[a]芘研究

采用超声萃取-高效液相色谱荧光检测法对土壤中苯并[a]芘含量进行定性、定量分析.土壤样品用正己烷/二氯甲烷(1+1)超声萃取,萃取液经硅胶柱或佛罗里硅土柱净化浓缩定容,乙腈-水为流动相,线性梯度洗脱,流速为1.0 mL/min,荧光检测器激发波长为280 nm,发射波长为420 nm,外标法峰面积定量.结果显示:该方法检出限低,苯并[a]芘的检出限为0.15μg/kg.这种方法具有很好的精密度,相对标准偏差为3.9%~8.4%.实际水样加标回收率范围在72.5%~85.8%.能够满足土壤的监测要求.     

Determination of 4-nonylphenol in carp blood samples by solid phase extraction and chromatographic techniques

In this study, selective methods were developed for isolation, purification, separation and determination of 4-nonylphenol (4NP) in biological samples. Several methods such as high-performance liquid chromatography (HPLC) with fluorescence and diode array detection and gas chromatography coupled to mass spectromotry (GC-MS) are described for the simultaneous determination of 4NP. The nonylphenols in the plasma of fish were extracted through solid phase process by using octadecyl, polymeric and octadecyl endcapping sorbents. The average recoveries in plasma samples spiked with 4NP of levels 1?µg?mL^?1 were between 80–95% using added surrogate standards. The aim of this study was to determine whether trace amounts of 4NP in fish plasma samples could be detected by solid phase extraction and chromatographic methods (HPLC, GC-MS). This technique of monitoring the levels of endocrine-disruptors in plasma samples is consistent, reliable as well as inexpensive.     

Polycyclic aromatic hydrocarbons in medicinal plants from Syria

The levels of 16 US Environmental Protection Agency polycyclic aromatic hydrocarbons (EPA PAHs) in 10 medicinal plants in different used parts of plant (leaves and flowers) have been determined. The analytical method consists of sample preparation by ultrasonic extraction with dichloromethane followed by silica gel clean-up. Subsequently, the analysis was carried out by reversed-phase high-performance liquid chromatography (HPLC) coupled to both ultraviolet and fluorescence detections in series to insure the detection of all 16 EPA PAHs. It was observed that the sum of the 16 PAHs (ΣPAHs) in the investigated medicinal plants ranged from 47 to 890 μg kg^–1 where the highest ΣPAHs was found in Sage plant sample. Light PAHs were dominants in all studied medicinal plants. The sum of eight genotoxic PAHs (ΣPAH8) have shown a better indicator of the degree of contamination with carcinogenic PAHs compared to benzo[a]pyrene in these products.     

Rapid liquid chromatographic analysis of Metoclopramide in pharmaceutical preparations

A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively.     

The estimation of bioconcentration factors of aromatic hydrocarbons by high‐performance liquid chromatography

The determination of Bioconcentration Factors (BCF) via HPLC capacity factors (k') has been studied, including the effect of column type and mobile phase composition on the correlation between log BCF and log k’. Values of BCF correlate well with the phenylsilica column capacity factors. The phenylsilica column followed by C18 column give better correlations than either C8 or C2 column. The use of HPLC with phenylsilica as stationary phase and methanol‐water as mobile phase in the prediction of BCF can be at least as good or better than the use of n‐octanol/water partitioning system. There are no significant differences in the correlations between log k’ and log BCF with the changes of methanol concentration in the mobile phase, and it seems that a high proportion of methanol in the eluent is required to obtain good results.     

Evaluation of linear alkylbenzenesulfonate (LAS) biodegradability in sediment by solid‐phase extraction and HPLC analysis

The linear alkylbenzenesulfonate (LAS) sorption on environmental sediments has been known long ago. Their high concentrations reflect the massive input of these chemicals from household and industrial uses. However few attempts were made to identify biodegradation metabolites of LAS in sediment. In this report, a method for the determination of these compounds in sediment samples by high‐performance liquid chromatography (HPLC) is described. The first step of our work was performed by solid‐phase extraction with octadecyl‐bonded silica (C18) mini‐columns and provided a suitable recovery of LAS (90 ± 5%) and most metabolites. Furthermore, laboratory investigations led to study the behaviour of LAS in sediment. The environmental samples used for this purpose were collected from a pond (named étang de Bolmon) located in the French Mediterranean coast. Our results were in agreement with an aerobic biodegradation process of LAS that occurred only with high values of sediment redox potential and needed the samples to be vigorously shaken to ensure adequate mixing and suspension of particulate material. In a stagnant sediment or under anaerobic conditions, LAS is not degraded. p‐Sulfophenylacetic acid and p‐sulfocinnamic acid were evidenced as predominant metabolites and were found not to be persistent.     

离子液体分析方法研究进展

离子液体(ILs)由于挥发性小和化学稳定性高常称为绿色溶剂而得以广泛生产与应用.同时由于水溶性高和难降解可能给水生生物带来潜在危害,已逐渐引起广大环境化学工作者的关注.如何有效地分离分析ILs是研究其迁移、转化等环境行为及生物毒性的首要问题.为此,本文系统论述了反相液相色谱法、离子对-反相液相色谱法、极性-反相液相色谱法、离子色谱法、毛细管电泳及等速电泳等方法分析ILs的研究进展,分析了各个方法的优缺点和适用对象,展望了ILs分离分析发展的未来趋势.     

高效液相色谱-荧光检测法同时测定畜禽粪便中4种磺胺类药物残留

建立了高效液相色谱-荧光检测法测定畜禽粪便中4种磺胺药物(磺胺甲基嘧啶(SM1)、磺胺氯哒嗪(SCP)、磺胺邻二甲氧嘧啶(SDM’)、磺胺喹噁啉(SQ))的方法.样品用25 mL甲醇提取3次,合并提取液,浓缩干燥,用0.1 mol.L-1的HCL溶解残渣,经荧光胺衍生化后,用反相C18柱为分离柱,以乙腈∶0.5%乙酸=40∶60(V/V)为流动相进行洗脱,20 min内分离4种药物.在0.05—5.00μg.mL-1范围内,4种磺胺类药物的峰面积与质量浓度的线性关系良好(R2≥0.999),SM1、SCP、SDM’、SQ的定量限(LOQ)分别为2.3、6.3、4.3和9.6μg.kg-1;添加水平为50、100、1000μg.kg-1时,SM1、SCP、SDM’、SQ的回收率分别为74.91%—81.82%、78.45%—91.43%和86.10%—92.88%,RSD小于8.82%.     

硝基化合物的高效液相色谱(HPLC)分析

硝基化合物是炸药废水的主要成分,大部分硝基化合物具有较高的毒性.本文对奥克托今、黑索今、1,3,5-三硝基苯、1,3-二硝基苯、硝基苯、2,4,6-三硝基甲苯、2-氨基-4,6-二硝基甲苯、2,4-二硝基甲苯共8种硝基化合物的紫外光谱和液相色谱分离条件进行了研究,其最佳检测波长分别为228 nm、227 nm、227 nm、237 nm、272 nm、230 nm、226 nm、244 nm.本文建立了8种硝基化合物的高效液相色谱测定方法,色谱条件为:色谱柱为ZORBAX SB-C18(3.0 mm×250 mm,5μm),检测器为紫外检测器,流动相为甲醇-水(50∶50),流速为0.5 mL.min-1.水中8种硝基化合物可以在13 min内得到较好的分离,检出限均≤0.8 ng,回收率大于95%.     

响应面法优化测定水体中微囊藻毒素

针对水体中低浓度微囊藻毒素(MC-RR和MC-LR)的富集、淋洗、洗脱等前处理环节,采用单因素响应面优化法探讨微囊藻毒素前处理的最佳条件。结果表明:采用体积分数为25%的甲醇水溶液能够取得最佳淋洗效果,由One Factor设计优化得到体积分数为75%的甲醇水溶液作洗脱剂,MC-RR和MC-LR最佳回收率为89.4%和90.7%。方法在0.100 mg/L~5.00 mg/L范围内线性良好,MC-RR和MC-LR的检出限分别为0.07μg/L和0.04μg/L,实际水样加标回收率分别为80.6%和84.9%,平行测定结果的RSD分别为1.6%和2.4%。