【作者】 谢原利；

【导师】 王沫； 饶竹；

【作者基本信息】 华中农业大学 ， 农药学， 2009， 硕士

【摘要】 毒杀芬具有高毒、高残留、难降解、容易被生物富集及远距离迁移等特性,是一种持久性有机污染物,目前已成为环境监测的重点目标。毒杀芬组成复杂,在土壤和水体等环境样品中的准确定量分析一直是有机污染物分析中的难点。本文对土壤和水体中毒杀芬的提取、净化、检测技术进行了系统研究,分别建立了加速溶剂萃取-负化学电离质谱法测定土壤中的毒杀芬;圆盘固相萃取-负化学电离质谱法测定水体中的毒杀芬,建立的检测方法方便、快捷、环保、准确、灵敏度高、精密度好,满足现代绿色分析技术的要求。文中采用现在国内应用较少的气相色谱-负化学电离质谱联用技术（GC-NCI/MS）与气相色谱-电子轰击电离质谱联用技术（GC-EI/MS）、气相色谱-电子捕获检测技术（GC-ECD）对毒杀芬的检测方法进行了对比研究。结果表明,GC-NCI/MS、GC-EI/MS、GC-ECD三种方法的仪器检出限分别为0.1ng/mL、5ng/mL、0.4ng/mL。GC-EI/MS具有很好的定性能力,但是检出限比较高,无法实现样品中痕量及微量毒杀芬的检测;GC-ECD虽具有和GC-NCI/MS相当的检出限,但无法实现对毒杀芬的准确定性和定量;GC-NCI/MS不仅具有很低的检出限,而且具有很强的定性、定量功能,在三种方法中最适合基质复杂、痕量或微量样品中毒杀芬的检测。单一净化技术对复杂基质样品无法达到较好的净化效果,本文比较研究了磺化法、弗罗里硅土、硅胶、氧化铝、Cleanert PestiCarb活性碳黑等对毒杀芬的净化效果,选定Cleanert PestiCarb活性碳黑与弗罗里硅土组成的复合层析柱净化样品,毒杀芬回收率为87.5%～97.9%,精密度（n=7）为5.05%～12.25%。加速溶剂萃取与微波辅助萃取是新型的固体样品前处理技术,本文将其用于土壤样品中毒杀芬的前处理方法研究。加速溶剂萃取方法中优化了萃取溶剂、萃取压力、萃取温度、萃取时间、循环次数等参数;微波辅助萃取实验中优化了提取溶剂、微波功率、萃取温度、萃取时间等参数;优化后的两种方法的平均回收率分别为102.5%、95.2%,明显高于经典索氏提取方法的回收率79.6%。两种方法均可以用于土壤样品中毒杀芬的提取,微波辅助提取虽一批次可以处理24个样品,但相对加速溶剂萃取具有操作步骤较多、溶剂用量大、安全系数小等劣势。在优化的加速溶剂萃取实验条件下,重复七次实验,得到的方法平均回收率为92.2%～105.6%,方法检出限为0.1-3.0ng/g,精密度为2.97%-12.35%。实验表明,加速溶剂萃取具有操作简单、高效、环保等优点,是一种方便、有效的提取方法。GDX-502树脂是国产的一种比较好的吸附剂,目前主要用于酚类化合物的富集提取。本文将GDX-502树脂用于装填固相萃取小柱,选用Empore^TM-C18 DISK作为固相萃取膜,优化了两种前处理方法中的样品pH值、水样流速、洗脱溶剂等条件。结果表明,圆盘固相萃取的回收率为90.5%～103.1%,稍高于固相小柱萃取的回收率78.4%～95.3%,并且分析效率是后者的3倍,但前两种方法的回收效果明显高于液-液萃取的66.7%～86.7%。采用优化后的圆盘固相萃取方法处理七个重复水样,方法检出限达0.5-30ng/L,精密度为3.64%-10.16%。本文利用上述建立的土壤和水体中毒杀芬残留检测方法对实际样品进行检测,结果表明方法实用,检测数据可靠。更多还原

【Abstract】 As one of the most important group of Persistent Organic Pollutants （POPs）, Toxaphene, with intense toxicity, high residuary, hardness of being metabolized, easier to be enriched by biology and with long-range transportability, so that ,it have stirred interest in the study of Environment Science. Up to now, Toxaphene has become main object in environment investigation. The complexity of the toxaphene mixture has intrigued and challenged analytical chemists for decades, and it is still difficult to quantitative analysis. The present thesis studied systematism the process of detection toxaphene, and covered toxaphene extraction, cleanup and detection technique. Moreover, the method of toxaphene analysis in soil by ASE - NCI/ MS, and analysis the object in water by solid-phase disk extraction （SPE） - NCI/MS were developed. These methods are convenient, fast, environmental protection, high sensitivity, accuracy, good relative standard deviation and content with Green Analytical Chemistry’s requirement.Comparative study of using GC-NCI/MS, GC-EI/MS, GC-ECD to detecting toxaphene was conducted, the GC-NCI/MS technique has few applications in china. The equipment detection limit was 0.1ng/mL,5ng/mL,0.4ng/mL. The accurate qualitative and quantitative of tocxaphene can’t be achieved by GC-ECD,the GC-EI/MS can’t detect trace samples, but GC-NCI/MS method not only has a very low detection limit, but also have a very strong qualitative capacity, which is showed to be the best detection method.The co-cleanup techniques of solid phase extraction with florisil column, silica gel column, alunima column and Cleanert PestiCarb which were used to eliminate the recoveries of toxaphene. The average recoveries of the co-cleanup technique by Cleanert PestiCarb and Florisil column was the best, the recoveries of toxaphene was ranged from 87.5% to 97.9%, the relative standard deviation was in range of 5.05% to 12.25%.The ASE and MAE were modern pre-treatment technology of solid sample. The power, solvent, pressure, temperature, and times were optimized. The average recoveries of two optimized mothods were 102.5% and 95.2%, they were significantly higher than 79.6% of the SE method. Two methods can be used in soil sample’s extraction, MAE can deal with twenty-four samples at the same time, but it need more solvent, more steps and not safe than ASE. In the optimized conditions of ASE, the average recovery was 92.2%- 105.6%, the MRL were 0.1-3.0ng/g,the precision is 2.97%-12.35% （n=7）,so it was suitable to be used in laboratory.Three methods of liquid - liquid extraction （LLE）, solid-phase column extraction （SPE column） and solid-phase disk extraction （SPE disk） were used in pre-treatment of water samples. In SPE methods we selected Empore^TM-C18 DISK membrane and GDX-502 resin which made in china was used to the enrichment of phenolic compound. Some factors influencing the extraction efficiency of SPE method, such as pH value of water sample, extraction pressure and elution solution were studied. The result indicated that the average recovery of the LLE, the column SPE and the disk SPE were 66.7%-86.7%,78.4%-95.3% and 90.5%-103.1%, respectively, but the efficiency of the disk SPE was three times than the column SPE. The MRL of the SPE disk was 0.5-30ng/L, the precision is 3.64%-10.16% （n=7）. This SPE disk method has fast flow, high, absorbability, lower counter pressure, so it has been used more widely in domestic and abroad these years.Finally, the established pretreatment and detection method were applied successfully to soil and water samples obtained from different regions for the determination of toxaphene residue. The results showed that most of samples had been polluted in different levels. The method has been proved to be credible.更多还原