Lead Speciation Analysis And Its Affect To Borvine Serum Albumin

Soil is an important part of terrestrial ecosystem,and offer habitat for most of the organisms in the earth.Soil is closely related to the water safety,grain produce,biodiversity and climate stability,so soil plays an important role in the human's activities.The soil pollution of heavy metal has get increasing attention in recent years with the acceleration of industrialization and urbanization.The soil pollution of heavy metal not only decrease the quality,but also threat the growth of animals and plants,furthermore,heavy metal can accumulated in the human body through the food chain,and then cause harm to human health.Therefore,the heavy metal pollution in soil should be solved as soon as possible.In this study,Pb was selected as the objective,the extraction condition of supercritical fluid extraction and accelerated solvent extraction were optimized,and the comparison of the two extraction methods were also carried out to evaluate these two extraction methods.Finally,multiple spectroscopy techniques were applied to evaluate the toxicity of different forms of lead to Bovine serum albumin The main results was as follows(1)Trimethyllead chloride and triethyllead chloride were selected to carried out speciation analysis,the extraction condition of supercritical fluid extraction(SFE)and accelerated solvent extraction(ASE)were optimized,and the comparison of the two extraction methods were also carried out to evaluate these methods.The best conditions of supercritical fluid extraction were:80?,25MPa,20minof static extraction,20min of dynamic extraction.5%(v/v)methanol.The best condition of accelerated solvent extraction we2 cycles and 90s of purge time.The extraction efficiency was all above 90%under the best condition for both of the two extraction methods and good repeatability was observed.The extraction time of ASE was 15min while the SFE was 40min,which saved a lot of extraction time.However,SFE had less collection volume,which make it possible to escape the nitrogen concentrations and improve the accuracy of an analysis.(2)The fluorescence measurements,UV-visible absorption measurements and circular dichroism studies were carried out to clarify the damage of inorganic lead and trimethyllead chloride to Bovine serum albumin.A molecule docking investigation was carried out to learn about the binding mode.The results showed that there was a static quenching and one binding site for both inorganic lead and TML to Bovine serum albumin.In terms of the interaction force,there was a hydrophobic force between inorganic lead and Bovine serum albumin,and a Van der Waals forces between TML and Bovine serum albumin.The UV-Visible absorption measurements clarified that the microenvironment of.Bovine serum albumin changed,and the hydrophobicity enhanced under the pollution of TML or inorganic lead.