ABSTRACT
Novel aminopropyl-functionalized periodic mesoporous organosilicas (APMO) were successfully prepared by co-condensation of 1,2-bis (triethoxysilyl) ethane (BTSE) and 3-aminopropyltriethoxysilane (APTES) with the template of cationic surfactants cetyltrimethylammonium chlorine (C_(18)TAC) in basic medium.With the characterization measurements of powder X-ray diffraction (XRD),FT-IR and scanning electron microscopy (SEM) so on,APMO had such advantages as good monodisperse microshperes,uniformly orderd mesopore and large specific surface areas.These mesoporous materials were directly considered to be the chromatographic stationary phases and analyzed by HPLC evaluation.During the research,the as-prepared APMO column had better permeability and three polycyclic aromatic compounds realized separation.In addition,the as-prepared APMO column had certain advantages in fast analysis.
ABSTRACT
Objective To establish the method of high performance liquid chromatography and hydrid genesis atomic fluorescence spectroscopy(HPLC-HGAFS) about arsenic species in urine of rats treated with sodium arsenite.Methods The solution containing 15 mmol/L(NH4)2HPO4(pH=6.0)was used as the chromatographic eluant,the flow rate of which was 1.0 ml/min.The parameters of HPLC-HGAFS consisted of multiplier negative high voltage,hollow-cathode lamp's joint current and co-current,the flow rate of carrier gas,the flow rate of barrier shield gas,supporting liquid and reducing agent,which were 285 V,80 mA,36 mA,400 ml/min,600 ml/min,7%HCl and the mixed liquor of 1.5%KBH4 and 0.35% KOH respectively.Results The linear range of method was 20-100 ?g/L,and the linearity of regression equation of iAs3+,iAs5+,DMA was better.The lowest detection concentration of iAs3 +,iAs5 +,DMA in urine were 12.03,6.67 and 8.66 ?g/L respectively and all of the coefficient correlation were ≥0.98.The average recovery rates of DMA were 96.5%-103.4% and RSDs were 0.39%-1.26%.Conclusion The method has been proved accurate,sensitive and is applicable to the determination of arsenic species in urine.
ABSTRACT
Objective To establish stable and convenient atomic fluorescence spectrometry to determine selenium concentration.Methods The samples were digested by nitric acid-perchloric acid and the selenium was determined by hydride generation-atomic fluorescence spectrometry with step-flow injection technology in NaBH4 acid and 100 g/L K3Fe(CN)6 system.Results The relative standard deviation of the method was less than 5%,the concentration of detection limits was 0.81 ?g/L and the recovery rate ranged from 93.1% to 102.2%.Conclusion Atomic fluorescence spectrometry was convenient and reliable in determining solenium,the digest method of test tube was better than that of normal electrothermal board.