【作者】 范春影；

【导师】 付华峰；

【作者基本信息】 郑州大学 ， 无机化学， 2013， 硕士

【摘要】 分散液液微萃取和固相萃取是近年来发展起来的新型的样品预处理技术。分散液液微萃取是基于三相萃取体系的方法,由于乳浊液的形成,萃取剂和样品溶液的接触面积大大增加,萃取可迅速完成。该方法简便,快速,成本低,富集倍数高,可用于环境和药物分析。固相萃取是以固体吸附剂作为萃取剂吸附液体样品中的某些组分,再选用合适的洗脱剂将目标分析物洗脱下来,从而达到目标分析物的分离和富集,可用于废水中金属离子的分离测定。论文可分为四部分：第一章：对液相微萃取和固相萃取的分类和发展做了系统的总结。第二章：将修饰Fe3O4纳米小球均匀预分散在正辛醇相中,利用分散液-液微萃取,拟定了快速、直接测定有机化合物log P新方法。修饰过的磁性纳米球有两个作用,第一：分散在正辛醇中提供磁力从而用磁铁可以使两相分离；第二：正辛醇和其内部的磁性内核相互作用阻止在液-液微萃取过程中乳状液的形成。有机化合物可在3min之内在两相达到分配平衡,可通过磁铁吸引含有修饰Fe3O4纳米小球内核的正辛醇小液滴,实现两相快速完全分离。在萃取过程中,疏水性Fe3O4纳米小球表面被正辛醇相包围,失去对测定化合物的吸附能力,因此Fe3O4纳米小球对测定有机化合物分配平衡的影响很小。通过测定了17种不同有机化合物,logP值在0.60-4.90范围内,测定结果与文献结果一致。与其他直接测定方法相比,该方法快速、准确、简单、样品消耗少。第三章：将修饰Fe3O4磁性纳米小球预分散在正辛醇相中,利用分散液-液微萃取结合高效液相色谱,提出了快速、直接测定药物与血清蛋白结合率的新方法。当药物与血清蛋白结合平衡后,将药物血清溶液加入到含有修饰Fe3O4纳米小球内核的正辛醇中。在3000r/min涡旋速度下,未与蛋白结合的药物,由于疏水作用进入正辛醇相。溶液中游离药物在5min之内在水相和正辛醇相达到平衡。通过磁铁吸引含有磁性修饰Fe3O4纳米小球内核的正辛醇小液滴,实现两相快速完全分离。用高效液相色谱分别测定药物与血清蛋白结合前后药物溶液的浓度,进而计算药物蛋白结合率。通过测定了不同血清蛋白结合率的6种药物,蛋白结合率在10%-100%范围内,测定结果与文献值一致。该方法快速、准确、简单、重复性好。第四章：制备了一种新型的pH敏感型固化单宁酸壳聚糖材料,用原子吸收光谱法,研究了固化单宁酸壳聚糖对Cu2+的吸附性能。用紫外扫描研究了不同pH(1-6)对Cu2+吸附和脱附的吸收曲线,pH=1-6的HCl脱附的Cu2+的量与在pH=1-6下未吸附的Cu2+的量保持一致,表明了固化单宁酸壳聚糖对Cu2+吸附和脱附过程的高度可逆性及固化单宁酸壳聚糖的pH敏感性。由固化单宁酸壳聚糖吸附Cu2+前后的红外谱图可知,固化单宁酸壳聚糖的-NH2和-OH与金属离子发生配位作用,在酸性条件下,溶液中的H+优先与-NH2作用生成-NH3+,能解吸掉金属离子。探讨了吸附时间、温度和Cu2+的不同初始浓度对吸附性能的影响。研究了固化单宁酸壳聚糖对Cu2+的吸附动力学,得出该吸附符合二级动力学。通过用0.010mol·L-1HCl脱附Cu2+,对该固化单宁酸壳聚糖循环利用10次,良好的吸附和脱附效果表明该固化单宁酸壳聚糖具有很好的再生性。通过富集1L浓度分别为0.50mg·L-1,0.10mg·L-1,0.020mg·L-1,0.010mg·L-1纯水溶液中的Cu2+,回收率分别达到99.81%,99.92%,99.73%,97.65%,表明了固化单宁酸壳聚糖良好的富集性,探讨了Pb2+、Cd2+、Zn2+、Co2+、Ni2+等金属离子对测定Cu2+的干扰及对自来水和矿泉水中的Cu2+进行了加标实验,Cu2+回收率均在95%-105%之间,表明该方法可准确测定水样中的痕量Cu2+含量。更多还原

【Abstract】 Dispersive liquid/liquid microextraction (DLLME) and solid phase extraction (SPE) are the novel sample pretreatment technology. DLLME is based on the ternary component solvent systems, as the formation of cloudy solution, the surface area between the extracting solvent and the aqueous sample becomes very large, so the equilibrium state is achieved quickly. The advantages of DLLME include simplicity of operation, rapidity, low cost, high recovery, high enrichment factor and environmental benignity. It can be used for Environmental and Pharmaceutical Analysis. Solid phase extraction is a method which using solid material as sorbent to extract analyte from sample solution, and then the analyte can be eluted by appropriate eluent. So it can realize the separation and enrichment of analyte. This method can be used for the separation and determination of metal ions in the wastewater. This paper is composed of four chapters.The first chapter gave a main summary for the classification and development of DLLME and SPE.The second chapter:A new direct method for log P determination by dispersive liquid/liquid microextraction (DLLME) coupled with derivatized magnetic nanoparticles (DMNPs) predispersed in1-octanol phase is discussed. First, the aim of DMNPs predispersed into1-octanol phase was to provide the magnetic force when an ultrastrong magnet was used to separate the two phases. Second, the interaction of1-octanol with inner DMNPs nuclei prevented emulsion formation in the DLLME process. The equilibrium of model compound between the two phases was reached in less than3min. The two phases were separated quickly by a super magnet because model compounds in the two phases did not interfere with each other. Moreover, interruption of absorption of DMNPs due to the partition equilibrium of the model compound was negligible. Seventeen model compounds of varied log P values were measured using this method. The log P values fell in the range of0.60to4.90, which was in agreement with the published results. This method is a rapid, accurate and facile method for direct measurement of log P values.The third chapter:A novel rapid direct method has been developed for determination of drug-protein binding by dispersive liquid/liquid microextraction (DLLME). Modified Fe3O4nanoparticles were firstly predispersed into1-octanol phase. The sample solution was added to the1-octanol phase with modified Fe3O4nanoparticles nulcea when the equilibrium of drug and serum protein binding was reached. The solution was swirled on a vortex agitator at the speed of3000rpm, the unbound drug was extracted into the1-octanol phase for its hydrophobic property. The equilibrium of free drug between the two phases was reached in5min and the two phases were separated quickly by an ultrastrong magnet. The amounts of drug concentration before and after drugs and serum protein binding were analyzed by HPLC, and then the drug-protein binding was calculated. The novel method was evaluated with6reference drugs in the drug-protein binding range from10%to100%and the results obtained were in good agreement with experimental data in the literature. This novel direct method was very quick, accurate and simple.The fourth chapter:We report on a highly reversible method for enrichment and determination of trace Cu2+by flame atomic absorption spectrometry. It is making use of pH-responsive chitosan immobilized tannin. These chitosan immobilized by the tannin exhibited a good performance for the determination of Cu2+ion. The effect of pH on the adsorption and desorption were examined by UV spectral scanning, the amount of unadsorbed Cu2+at pH1-6is coincide with the amount of Cu2+desorbed by HC1(pHl-6). The results indicated the highly reversible performance of adsorption-desorption and the pH-responsive of chitosan immobilized tannin. The function guoups of-NH2and-OH can form coordination bond with metal ions,-NH2can protonize under acid condition, so the hydrogen ions take places of metal ions in the acid condition, and the metal ions can be desorbed. The effects of adsorption time, the temperature and initial metal concentration on the adsorption rate were also examined. The adsorption follows the pseudo-second order kinetics. The adsorption-deadsorption test of the chitosan immobilized tannin was repeated10consecutive times, and the results show the good regeneration of chitosan immobilized tannin. The enrichment of Cu2+was conducted with1L of0.50mg·L-1, 0.10mg·L-1,0.020mg·L-1,0.010mg·L-1respectively, and the enrichment rate was99.81%,99.92%,99.73%,97.65%respectively. We discussed the interference to Cu2+of interference ions such as Pb2+、 Cd2+、 Zn2+、Co2+、Ni2+, and the content of Cu2+in tap water and mineral water was determinated, The recovery was95%-105%, so the method can be realized the enrichment of trace Cu2+.更多还原