Font Size: a A A

Studies On The Property, Extraction And Determination Of Organotin Compounds

Posted on:2009-12-08Degree:DoctorType:Dissertation
Country:ChinaCandidate:X P WangFull Text:PDF
GTID:1101360245463110Subject:Analytical Chemistry
Abstract/Summary:
Organotin compounds(OTs)are widely used as insecticides, fungicides, bactericides, acaricides, wood preservatives, plastic stabilizers and antifouling agents. Therefore they are found in numerous environmental substance, industry products and crop, such as water, sediment, tissues, plastic, textile, food etc. Authough OTs are useful and have been widely used, they are poluting environment and threating life. Research results indicated has shed some light on the threation that OTs, specially the tri-substituted species, affects incretion and nervous system greatly. What's worse, halobios, having the enriching ability, will get toxicosis and perform bad mutation even under the condition of low concentration of OTs. Therefore, it is necessary to develop a quick and effective method to detect OTs.The investigation on organotin compounds was carried out in this thesis. Microwave-assisted extraction(MAE)was used to extract OTs from the solid sample and on-line solid-phase extraction(SPE)was employed to extract OTs from the liquid sample. The interactions of OTs and DNA were also studied in the molecular level. MAE was used to extract OTs from flour. Extraction temperatures, extraction solvents and extraction time were optimized. Compared with conventional methods, MAE provided high extraction efficiency within a short time. And the normal-phase HPLC was applied to determine OTs. Acetic acid-hexane(20/80)medium was chosed as extraction solvent. The separation was performed in the isocratic mode on cyanopropyl column with a mobile phase of hexane-acetonitrile-THF(97/1/2). Methanol and water system as extract solvent was replaced by hexane system to simplify experiment process after MAE. The main advantage of normal-phase chromatography is to separate various OTs in very short time.In order to identify its wide application, MAE were used to extract OTs from textile and plastic samples. The conditions, including temperature, extration time and extraction solvent, have been optimized. And another new method has been developed to analyze the plastic sample. The plastic sample was dissolved fully in organic solvent first. This dope were coated on glass slide and then put into the extraction vessel. Not only was the OTs on the surface of the sample extracted, but also that inside. Then sensitive detect of OTs by electrospray ionization mass spectrometry(ESI-MS)was performed on the basis of multiple reaction monitoring(MRM)mode. When the MRM mode was used to quantify OTs, the specifical pairs were used as monitoring ions and the matrix effect was decreased. The accuracy and sensitivity were compared with SIM mode.An on-line technique based on solid-phase extraction coupled on-line with high-performance liquid chromatography ( SPE–HPLC ) has been developed for the determination of OTs in water and plasma samples. The system consists of an Agilent 1100 two-dimensional liquid chromatograph, which was equipped with an injection valve, a 10-port switching valve, a quaternary pump, a heated column compartment, a UV detector and a LC workstation, and an additional elite high pressure pump. The samples were injected directly into a SPE column and the matrix was washed out. By rotation of the switching valve, the analytes trapped on the SPE column were eluted into the analytical column with chromatographic mobile phase and detected by the UV detector. As for the water sample, a C18 SPE column was used. As for the plasma sample, MF Ph-1 column was used. A MF Ph-1 column packed the restricted access materials(RAM)was used as the SPE column for analyzing the plasma sample. This column possesses long hydrophilic chains in the external and hydrophobic phenyl in the internal in order to access of large molecules such as proteins and retain the OTs. Compared with the off-line method, the on-line technique is more advantageous with respect to time for analysis, solvent consumption and analytes loss. Moreover, the sensitivity of the method has been improved as the whole extract was transferred from SPE column to the analytical column.The interactions of eight kinds of OTs with Deoxyribonucleic acid(DNA)were investigated by UV and fluorescent spectrometry(FS). The influences of species and co fluorescent ncentration of OTs on the interaction of OTs with DNA were studied. It can be concluded that different kinds of OTs interacts with DNA via different interaction modes.
Keywords/Search Tags:Determination
Related items