ABSTRACT
SuperparamagneticSiO2@Fe3O4microspherewithcore-shellstructurewaspreparedbythe method of hydro-thermal and St?ber method, and modified by (3-aminopropyl) triethoxysilane ( APTES) . The obtained amino-Fe3 O4@SiO2 microsphere with controlled surface charge properties was characterized by SEM and TEM, and the surface electric property of amino-microsphere was investigated by Zeta potential measurement. The microsphere was used to extract DNA from human blood, and the solid phase extraction method by microspheres was developed. The mechanism of action between Aminated-Fe3 O4@SiO2 microsphere and DNA was explored, and the gel electrophoresis and PCR test were done on the extraction product. The result showed that genomic DNA with high purity was successfully extracted from whole blood by using amino-Fe3 O4@SiO2 microsphere, with the extraction rate about 70%, the saturated adsorption capacity for DNA was about 40 ng/μg, and the elution could be directly used for further bio-analysis.
ABSTRACT
Based on the selective permeability of cationic exchange membrane and the characteristic of electri cal driven, a new and non-damage apparatus that can be used to separate compounds with different electric property was built to capture and enrich DNA.λ-DNA, as a model compound, was used to study the charac teristic of capturing and enriching DNA in this device.Factors that might affect the efficiency such as voltage and flow speed were optimized and gel electrophoresis was done to study if DNA was denaturation, PCR was done to prove the concentration can be used to further bioanalysis.Results were got; the apparatus could used to capture and enrich DNA scathelessly under the condition of low-voltage, the concentrate multiple was 62, and the recovery efficiency was accessible to 47%, concentration can be used for the next bioanalysis.Auto matic, easy to handle and little organic reagent using made it be advantageous, it could be miniatured to com bine with other biochips.This method had a large application space in field of DNA extraction, purification and concentration.
ABSTRACT
Mammal metallothionein(MT) folds into two separate domains that exhibit different structure and metal binding propertity independently, the study of the strategy of metal ions binding with MT would give better understanding of their exact biological functional mechanisms. In this study, a method using eletrospray ionization mass spectrometry (ESI-MS) phase liquid chromatography and identified by ESI-MS. Different amounts of Cd or Cu were then added in MT-2a samples and ESI-MS was employed to determine the mass difference of MT in different samples. The results Cd2+4S11; while Cd is attached in separate binding sites for the formation of Cd2+3S9 cluster, which intermediately formed with five and six Cd ions were detected. For the Cuprous ions, it prefers to cooperatively bind in β-domain with the form of Cu4-MTβ. The binding form in β-domain would convert from Cu4 into more Cu binding form with the addition of Cu. When high concentration of Cu was added in samples, the result suggested that
ABSTRACT
An online enrichment-separation system of C18 and inductively coupled plasma-mass spectrometry (ICP/MS) with flow injection （C18-FI-ICP/MS） was established for the determination of trace heavy metals in seawater. The optimized experimental parameters including pH，C18 column，concentration of methol in elute and the velocity of elute were investigated. This system was applied to the online preconcentration , separation and determination of trace heave metals in seawater samples successfully. The detection limit (3σ) for Cd, Pb, Co, Ni and Zn was 0.03, 0.09, 0.1, 0.1, 0.3 μg/L respectively. The RSD of Cd, Pb, Co, Ni, and Zn for six measurements of seawater was 6.8%，3.4%，1.3%，2.6%，0.5%，respectively. The accuracy was verified with spiked recovery test. The recovery for five elements was 91.3%，95.1%，100.4%，100.3%，95.2%, respectively.