Determination of Trace Rare Earth Elements in Biological Samples by ICP-AES with Tungsten-spiral Electrothermal Vaporization Sampling

A method for determination of trace rare earth elements in biological sample by ICP-AES with tungsten-spiral electrothermal vaporization(TETV-ICP-AES)sampling has been developed in this work. Several influencing factors including desolvation and vaporization parameters,carrier gas flow rate and ma- trix effect were investigated in detail.Under optimal experimental conditions,the detection limits for La,Nd, Gd,Dy,Ho,Yb,Lu and Y were obtained in the range of 10^(-9)～10^(-11) g,and they are comparable to and,in most instances,better than those for the GFAAS and conventional pneumatic nebulisation-ICP-AES.The precision(RSD)obtained for this method is less than 6%.

Determination of Cd,Pb and Sr by Microwave Plasma Torch Atomic Emision Spectrometry Using an Electrothermal Vaporization Sample Introduction System

A method for the determination of Cd,Pb and Sr by microwave plasma torch(MPT)atomic emission spectrometry(AES)was developed.Th e samples were introduced into the MPT with an elec trothermal vaporization(ETV)device.The effects of some experimental conditions on the de-termination of Cd,Pb and Sr were examined.The effects of easily ionized elements on the emis-sion intensity of Cd,Pb and Sr were studied in detail.The detection limits for Cd,Pb and Sr are 2.4,4.0 and 1.3 ng/mL,respectively.

Determination of Trace Amount of Vanadium in High Purity Y_2O_3 by Electrothermal Vaporization－ICP－AES With Bi（PDC）_3 Coprecipitation

A new method for the determination of vanadium in high purity Y2O3 by fluorination assisted electrothermal vaporization-ICP-AES is presented in this paper. After the sample dissolved,the vanadium in the sample solution was coprecipitated with Bi(PDC)_3 at pH 3. 7. The precipitates were made into a slurry with the fluorinating agent PTFE and directly introduced into the graphite furnace for determination. The analytical results were obtained by aqueous calibration curve method. The detection limit of the method is 1. 1 ng/mL, the RSD is 2. 8% (n=10,1 5 ng/mL vanadium solution), and the recovery of vanadium added to real sample is more than 96%.

Studies on Volatilization of Zirconium from Electrothermal Graphite Furnace for Sample Introduction into Inductively Coupled Plasma

Element zirconium reacted with polytetrafluoroethylene (PTFE) dispersed in isopropanol-water mixture to form volatile fluoride when heated in an electrothermal graphite furnace, and the fluorides formed subsequently were vaporized into ICP for atomization and excitation. The technique provides a picogram detectkm limit and adequate precision of 4% relative standard deviation. Linear dynamic range covers over three orders of magnitude. The process of sample preparation it very convenient. It is expected that the method proposed is suitable for determination of other refractory elements.

Determination of Nickel and Palladium in Environmental Samples by Low Temperature ETV-ICP-OES Coupled with Liquid-liquid Extraction with Dimethylglyoxime as Both Extractant and Chemical Modifier

A novel method for the determination of nickel and palladium in environmental samples by low temperature ETV-ICP-OES with dimethylglyoxime（DMG） as both the extractant and chemical modifier has been developed. In this study, it was found that nickel and palladium can form complexes with dimethylglyoxime（0. 05%, mass fraction） at pH 6.0 and can be extracted into chloroform quantitatively. The complexes can be evaporated into plasma at a suita-ble temperature（ 1400℃） for ICP-OES detection. Under the optimized conditions, the detection limits of nickel and palladium are 0.48 and 0. 40 ng/mL, respectively, while the RSD values are separately 5.0% and 3.1% （p = 50 ng/mL, n = 7）. The proposed method was applied to the determination of the target analytes in environmental sam-ples with satisfactory results.

Direct Determination of Trace Silicon in Lanthanum Oxide by Using a Selective Volatility and Slurry Sampling-FETV-ICP-AES

A new method for determination of trace silicon in high purity lanthanum oxide by using electrothermal vaporization (ETV) ICP AES with polytetrafluoroethylene(PTFE) slurry as a fluorinating reagent has been proposed. Under the optimized experimental conditions, the fluorination reactions of analyte(Si) and matrix(La) with PTFE in the graphite furnace took place at high temperature, and the fractional volatilily between Si and La was observed. Based on this principle the matrix interference could be eliminated. The detection limit of Si was 4.0 μg·L -1 , and the RSD was 3.4%( C =0.2 mg·L -1 , n =10). The procedure proposed has been applied successfully to determine trace Si in La 2O 3 without any chemical pre treatment.