离子色谱-电感耦合等离子体质谱联用测定大气颗粒物PM2.5和PM10中的六价铬

建立了大气颗粒物PM_2.5、PM₁₀中六价铬（Cr（Ⅵ））的离子色谱-电感耦合等离子体质谱（IC-ICP-MS）检测方法。采用碳酸氢钠（NaHCO₃）溶液超声提取大气颗粒物样品中的Cr（Ⅵ）,并使用含有0.22 g/L 乙二胺四乙酸二钠盐（Na₂EDTA）的75 mmol/L硝酸铵溶液（pH 7.0）淋洗液通过离子色谱柱（AG7,50 mm×4 mm）分离出样品中的Cr（Ⅵ）,电感耦合等离子体质谱测定。标准溶液中Cr（Ⅵ）的质量浓度在0.05~5 μg/L范围内呈良好的线性关系,相关系数达0.9999,标准溶液测定的精密度为1.0%~4.0%,标准样品测定的相对误差为3.3%;纤维素滤膜适用于Cr（Ⅵ）的采样,将纤维素滤膜碱化后,Cr（Ⅵ）的回收率从75%增加到102%;样品在20 mmol/L碳酸氢钠溶液中超声30 min后上机测试,提取完全且回收率稳定;当采样体积为20 m³,方法的检出限为0.0004 ng/m³;采集并测定了PM_2.5及PM₁₀实际样品,样品的加标回收率为91.6%~102%,精密度为1.7%~7.6%。该方法高效、稳定、灵敏,适用于大气颗粒物中六价铬的测定。     

Combining Ammonium Pyrrolidine Dithiocarbamate/methyl Isobutyl Ketone Microextraction in an Inexpensive Disposable Pipette with Laser Ablation Inductively Coupled Plasma Mass Spectrometry for the Determination of Cd and Pd

This paper describes a new analytical method, using a combination of ammonium pyrrolidine dithiocarbamate/methyl isobutyl ketone (APDC‐MIBK) microextraction and laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS), for the determination of the concentrations of Cd and Pb in aqueous samples. Only 200 μL of organic solvent was used throughout the entire analysis process, with enhancement factors as high as 25. Recoveries from replicate analyses of natural water [NIST 1640(a)] containing mean concentrations of 3.1 μg Cd L^?1 and 9.3 μg Pb L^?1 were 95 ± 3 and 104 ± 4%, respectively. The corresponding detection limits were 0.6 μg L ^?1 for Cd and 0.9 μg L ^?1 for Pb. The main advantage of this approach is its simplicity in terms of sample preparation, as demonstrated by quantifying the levels of Cd and Pd in real samples, including tap water, groundwater, and seawater, using a standard addition method.     

Determination of cyanide,thiocyanate, cyanate,hexavalent chromium,and metal cyanide complexes in various mixtures by ion chromatography with conductivity detection

The first aim of this study was to develop a selective, sensitive, and reliable method for direct simultaneous determination of cyanate, thiocyanate, and hexavalent chromium by ion chromatography (IC) with conductivity detection. The other target was to successfully determine cyanides by utilizing same chromatographic system. Yet, since cyanides can not be detected by the direct method, free cyanide ions were converted into cyanate with chloramine-T at alkaline pH. In addition, strongly complexed metal cyanides were converted into cyanate by using photo-oxidation following chloramine-T. Total cyanate ion obtained from developed methods were analyzed with IC. The chromatographic separations on anion exchange column were accomplished by optimized multistep gradient eluent program using NaOH as the eluent. Proposed method was applied for the simultaneous determination of cyanide and hexavalent chromium in electroplating bath solutions and in industrial wastewater. Cyanide and hexavalent chromium could be measured in the linear dynamic ranges of 0.6–961.5 and 0.9–118.5 µmol L^?1, respectively. The limit of detection and limit of quantification of cyanide were 0.18 and 0.61 µmol L^?1, and these values for chromium(VI) were 0.26 and 0.86 µmol L^?1, respectively.     

Determination of Organotin Compounds in Wine by Microwave-Assisted Extraction and High Performance Liquid Chromatography–Inductively Coupled Plasma Mass Spectrometry

A new analytical procedure for the determination of five organotin compounds in several matrix wine samples is reported. The organotin compounds were extracted by microwave-assisted extraction with n-hexane. Extraction conditions, such as volume of n-hexane required, extraction temperature, and extraction time, were investigated and optimized by an orthogonal array experimental design. The determination of organotin compounds in the final extracts was carried out by liquid chromatography–inductively coupled plasma mass spectrometry. The procedure showed limits of detection between 0.029–0.049 µg · L^?1. The linearity was in the range of 0.5 to 100 µg · L^?1. The precision expressed as relative standard deviation (RSD) was below 9.43%. The developed method was successfully employed to analyze different matrix wine samples, and some analytes were detected at the level of 0.053 to 1.14 µg · L^?1.     

Determination of antimony species with high-performance liquid chromatography using element specific detection

A new method for the fast and simultaneous determination of Sb(III) and Sb(V) is presented involving the use of anion exchange high-performance liquid chromatography (HPLC), a complexing reagent in the mobile phase, and element specific detection with flame atomic absorption spectrometry (FAAS) or inductively coupled plasma mass spectrometry (ICP-MS). Chromatographic parameters such as nature and concentration of the complexing and eluting compounds and pH of the mobile phase were investigated in detail. Additionally, the separation of inorganic Sb(III) and Sb(V) from organically bounded antimony (as (CH₃)₃SbCl₂ and (CH₃)₃Sb(OH)₂) was investigated by using anion, and cation exchange, and reversed phase HPLC. Best separation was obtained with anion exchange HPLC under alkaline conditions. Cation exchange and reversed-phase HPLC were not useful for the separation of the above compounds. With FAAS concentrations in the upper mg L^–1 range are detectable, which is not sensitive enough for the analyses of environmental samples. When the chromatographic system was coupled to ICP-MS, the detection limits are in the lower μg L^–1 range. The method was applied to various environmental samples with anthropogenic and naturally elevated Sb concentrations.     

Determination of Titanium in Nano-Titanium(IV) Oxide Composite Food Packaging by Microwave Digestion and Inductively Coupled Plasma Atomic Emission Spectrometry and Inductively Coupled Plasma Mass Spectrometry

Titanium was determined in nano-titanium(IV) oxide food packaging by microwave digestion with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave digestion was optimized using different acid combinations. Both spectrometry techniques showed good reproducibility, repeatability, and recovery. For ICP-AES, the limit of detection was 5.0 mg kg^?1, the linear dynamic range was 100–5000 µ g L^?1, the average recoveries for blank samples spiked with titanium were between 94.7% and 100.1%, and the relative standard deviations were from 2.1% to 7.1%. By ICP-MS, the limit of detection was 0.3 mg kg^?1, the linear dynamic range was 0.5–200 µ g L^?1, the recoveries were 88.4%–96.3%, and the relative standard deviations were 6.3%–7.4%. These results indicated that methods were effective for the determination of titanium in food packaging.     

Evaluation of on-line desalter-inductively coupled plasma-mass spectrometry system for determination of Cr(III), Cr(VI), and total chromium concentrations in natural water and urine samples

We have developed a simple and convenient method for the determination of Cr(III), Cr(VI), and the total chromium concentrations in natural water and urine samples that use a flow injection on-line desalter-inductively coupled plasma-mass spectrometry system. When using aqueous ammonium chloride (pH 8) as the stripping solution, the severe interference from sodium in the matrix can be eliminated prior to inductively coupled plasma-mass spectrometry measurement, and the Cr(VI) level can be determined directly. To determine the total concentration of Cr in natural water and urine samples, we used H₂O₂ or HNO₃ to decompose the organic matter and convert all chromium species into the Cr(VI) oxidation state. To overcome the spectral interference caused by the matrix chloride ion in the resulting solutions, we employed cool plasma to successfully suppress chloride-based molecular ion interference during the inductively coupled plasma-mass spectrometry measurement. By significantly eliminating interference from the cationic and anionic components in the matrices prior to the inductively coupled plasma-mass spectrometry measurement, we found that the detection limit reached 0.18 μg L^− 1 (based on 3 sigma). We validated this method through the analysis of the total chromium content in two reference materials (NIST 1643c and 2670E) and through measuring the recovery in spiked samples.     

Preconcentration of total chromium on Dowex 50W-X8 resin loaded with 2-amino-benzenethiol

Application of Dowex 50W-X8 loaded with 2-amino-benzenethiol for preconcentration of total chromium (Cr(VI) and Cr(III)) in water samples and subsequent determination by inductively coupled plasma-atomic emission spectrometry was studied. The reagent 2-amino-benzenethiol loaded onto the resin effectively reduced Cr(VI) to Cr(III) and total chromium (both Cr(VI) and Cr(III)) formed chelate complex with the reagent in the Cr(III) valence state. Experimental parameters such as preconcentration time, solution flow rates, pH, and concentration of the eluent were optimized. The method has been applied for the determination of total chromium in seawater samples in the range of 0.1–200?µg?L^?1. A detection limit of 0.3?µg?L^?1 was achieved, and the relative standard deviation was about 5%.     

Optimization of the operating conditions using factorial designs for determination of uranium by inductively coupled plasma optical emission spectrometry

A critical evaluation of the determination of uranium by inductively coupled plasma optical emission spectrometry was performed using factorial designs (2³) involving the factors: acid concentration, radio frequency power and nebulizer gas flow rate. All of the experiments in this study were made for five emission lines, in the presence of nitric and hydrochloric acid. The results demonstrated that, between nitric and hydrochloric acid, the determinations in the presence of nitric acid were most sensitive. The factorial design showed that the nebulizer gas flow rate was the most significant among the factors studied for the five emission lines. Calcium in concentrations of 10 mg L⁻¹ was observed to cause suppression of the emission intensity for some lines. Iron (at least up to 10 mg L⁻¹) did not interfere in the emission intensity of uranium across the five lines studied. Another experiment evaluated simultaneously the effect of 13 other elements, and the results demonstrated that these elements did not affect the emission intensity of uranium for the lines chosen. The optimized method, using the line at 385.957 nm, allows the determination of uranium with limit of quantification of 31 μg L⁻¹ and precision expressed as RSD lower than 2.2% for uranium concentrations of either 500 or 1000 μg L⁻¹. The accuracy was confirmed by analysis of two laboratory reference materials. The developed method was applied to the determination of uranium in an industrial effluent collected from uranium-producing mine in Caetite City, Brazil. The sample was analyzed by inductively coupled plasma mass spectrometry ICP-MS, and the observed recovery was satisfactory.     

微波灰化-液相色谱-电感耦合等离子体质谱联用测定干食用菌中的三价铬和六价铬

建立了干食用菌中三价铬(Cr(Ⅲ))和六价铬(Cr(Ⅵ))的液相色谱-电感耦合等离子体质谱(LC-ICP-MS)检测方法。采用微波灰化技术对食用菌样品进行灰化处理,灰化样品用乙二胺四乙酸(EDTA)二钠盐稳定其中的Cr(Ⅲ),并使其保留在阴离子交换柱(250 mm×4.6 mm,10 μm)上;用含有60 mmol/L硝酸(pH 9.3)的流动相分离其中的Cr(Ⅲ)和Cr(Ⅵ),电感耦合等离子体质谱仪测定。标准溶液中Cr(Ⅲ)和Cr(Ⅵ)的质量浓度在0.5~50 μg/L范围内呈良好的线性关系,线性回归系数均达到0.9999。食用菌样品中Cr(Ⅲ)和Cr(Ⅵ)不同加入量的平均回收率为78.0%~90.7%,相对标准偏差小于4%(n=6);定量限均为0.5 μg/L。该方法稳定、可靠、灵敏,可满足干食用菌中Cr(Ⅲ)和Cr(Ⅵ)的测定。     

Speciation analysis of orthophosphate and myo‐inositol hexakisphosphate in soil‐ and plant‐related samples by high‐performance ion chromatography combined with inductively coupled plasma mass spectrometry

A novel method based on high‐performance ion chromatography inductively coupled plasma mass spectrometry employing strong anion exchange chromatography with HNO₃ gradient elution for simultaneous analysis of orthophosphate and myo‐inositol hexakisphosphate (IP₆) in soil solution and plant extracts is presented. As inductively coupled plasma mass spectrometry analysis of phosphorus at m/z 31 is hampered by N‐based interferences, ³¹P was measured as ³¹P¹⁶O⁺ at m/z 47 employing dynamic reaction cell technique with O₂ as reaction gas. Orthophosphate and IP₆ were separated within a total chromatographic run‐time of 12 min revealing a limit of detection of 0.3 μmol/L. The coefficients of determination obtained in a working range of 1–100 and 1–30 μmol/L were 0.9991 for orthophosphate and 0.9968 for IP₆, respectively. The method was successfully applied to extracts from three different soils as well as root and shoot extracts of Brassica napus L. The precision of three independently prepared soil extracts was in the range of 4–10% relative standard deviation for PO₄^3? and 3–8% relative standard deviation for IP₆. Soil adsorption/desorption kinetics for IP₆/orthophosphate were performed for investigating the sorption behavior of the two P species in the experimental soils.     

On-line preconcentration and determination of chromium in parenteral solutions by inductively coupled plasma optical emission spectrometry

A method for the preconcentration and speciation of chromium was developed. On-line preconcentration and determination were obtained using inductively coupled plasma optical emission spectrometry (ICP-OES) coupled with flow injection. To determinate the chromium (III) present in parenteral solutions, chromium was retained on activated carbon at pH 5.0. On the other hand, a step of reduction was necessary in order to determine total chromium content. The Cr(VI) concentration was then determined by difference between the total chromium concentration and that of Cr(III). A sensitivity enrichment factor of 70-fold was obtained with respect to the chromium determination by ICP-OES without preconcentration. The detection limit for the preconcentration of 25 ml of sample was 29 ng l⁻¹. The precision for the 10 replicate determinations at the 5 μg l⁻¹ Cr level was 2.3% relative standard deviation, calculated with the peak heights. The calibration graph using the preconcentration method for chromium species was linear with a correlation coefficient of 0.9995 at levels near the detection limits up to at least 60 μg l⁻¹. The method can be applied to the determination and speciation of chromium in parenteral solutions.     

Trace Determination of Manganese in Urine by Graphite Furnace Atomic Absorption Spectrometry and Inductively Coupled Plasma–Mass Spectrometry

This paper describes a simple and sensitive method for the determination of manganese in human urine by graphite furnace atomic absorption spectroscopy (GFAAS), which includes sample preparation by microwave digestion. Matrix modifier combinations, the digestion power, pyrolysis, and atomization temperatures were optimized. A mixture of 5.0 µg Pd(NO₃)₂ and 3.2 µg Mg(NO₃)₂ modifier presented the best performance. The optimal temperatures for pyrolysis and atomization were 1500°C and 1950°C, respectively. The GFAAS method was compared to inductively coupled plasma–mass spectrometry (ICP–MS) for the determination of manganese in urine. Analytical figures of merit for GFAAS and ICP–MS were: accuracy (3.46%, 2.19%), precision (3.61%, 5.84%), LOD (0.109 µg · L^?1, 0.015 µg · L^?1), LOQ (0.327 µg · L^?1, 0.045 µg · L^?1), and recovery (80–100%, 74–89%). Both methods were employed for the determination of Mn in urine and the results were compared statistically.     

Separation and chromium speciation by single-wall carbon nanotubes microcolumn and inductively coupled plasma mass spectrometry

Microcolumn packed single-walled carbon nanotubes (SWCNTs) were used as solid phase extraction adsorbent for chromium speciation coupled to inductively coupled plasma mass spectrometry for detection. The effects of the experimental parameters, including pH of the solution, sample flow rate, volume and concentration of eluent, sample volume and interfering ions, on separation and determination of Cr(III) and Cr(VI) were investigated in detail. It was found that Cr(III) was selectively sorbed on the microcolumn packed with SWCNTs in the pH range from 2.0 to 4.0, while Cr(VI) remained in solution. The retained Cr(III) was subsequently eluted with 2.0 mL of 1.2 mol L^?1 nitric acid. Under the optimum conditions, the detection limits based on 3σ criterion were 0.01 ng mL^?1 and 0.024 ng mL^?1 for Cr(III) and Cr(VI), respectively. The relative standard deviations were less than 5.0% (n?=?9, c?=?1.0 ng mL^?1). The method was successfully applied to the speciation of chromium in real samples including natural and waste water. The recoveries of spiked samples were higher than 92.5%.     

Radiochemical methodologies applied to determination of zirconium isotopes in low-level waste samples from nuclear power plants

The ⁹³Zr determination in low-level radioactive wastes generated at nuclear power plants is an important issue for waste disposal purpose. This paper describes an analytical methodology developed for ⁹³Zr determination based on selective separation using extractive resins associated with inductively coupled plasma mass spectrometry (ICP-MS) and liquid scintillation counting (LSC) measurements. The ⁹³Zr results obtained for waste samples were in a good agreement for both techniques and the detection limits of 0.045 μg L^?1 and 0.05 Bq L^?1 were obtained for ICP-MS and LSC techniques respectively.     

Speciation of chromium in waste water using ion chromatography inductively coupled plasma mass spectrometry

Ion chromatography (IC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was systematically investigated for determining the speciation of chromium in environmental samples. Firstly, the stability of complexes formed by Cr(III) with various aminopolycarboxylic acids was studied by electrospray ionization mass spectrometry (ESI-MS). The results showed that [Cr(EDTA)]⁻ was stable in solution. Secondly, various mobile phases were examined to separate Cl⁻ from chromium species by IC to avoid Cl⁻ interference. The separation of [Cr(EDTA)]⁻ and Cr(VI) was achieved on a new anion-exchange column (G3154A/102) using a mobile phase containing 20 mM NH₄NO₃ and 10 mM NH₄H₂PO₄ at pH 7.0 without Cl⁻ interference. Detection limits for chromium species were below 0.2 μg/L with a direct injection of sample and without prior removal of interferences from the matrix. Finally, the proposed method was used for the determination of chromium species in contaminated waters.     

Development of Cloud Point Extraction for Simultaneous Extraction and Determination of Platinum and Palladium Using Inductively Coupled Plasma Optical Emission Spectrometry in Platinum-Palladium Spent Catalysts

A new on-line cloud point extraction system coupled to inductively coupled plasma optical emission spectrometry was designed for simultaneous extraction, preconcentration and determination of trace amounts of platinum and palladium in platinum-palladium spent catalysts. This was based on the complexation of the metal ions with 1,8-diamino-4,5-bis(hydroxyamino)anthraquinone reagent in the presence of non-ionic surfactant of Triton X-114. After phase separation, the surfactant-rich phase was diluted with concentrated HNO₃ (70%, w/w); the analytes concentrations were determined by inductively coupled plasma-optical emission spectrometry. Several factors influencing the instrumental conditions and extraction were evaluated and optimized. Under the optimum conditions, the enhancement factors of the proposed method were 35.4 and 29 for platinum and palladium, respectively. The detection limits were 0.3 and 0.45 µ g L^?1. Finally, the developed method was successfully applied to the extraction and determination of platinum and palladium in platinum-palladium spent catalysts samples and satisfactory results were obtained.     

Rapid Determination of Dissolved Phosphorus in Environmental Waters Using Inductively Coupled Plasma Tandem Mass Spectrometry

Dissolved phosphorus (P), an important bioavailable nutrient element, is one of the key indicators of eutrophication levels, and has been routinely measured for decades in aquatic environments. The current EPA recommended colorimetric method has been criticized for its time-consuming step of sample preparation and generation of toxic waste through the use of heavy metal catalysts. In this study, a fast, accurate, and interference-free method for the determination of dissolved P in environmental waters based on inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) was developed. This ICP-MS/MS was operated in the MS/MS mode to provide an interference-free measurement. The developed method exhibited excellent linearity (R² = 0.9999) over a concentration range of 0.5–500 μg L^?1, with a limit of detection of 8.1 ng L^?1 in 5% nitric acid solutions. The recoveries (90%–105% in water samples) and the concentrations determined by this method were in good agreement with those determined using the recommended colorimetric method. Comparing with the colorimetric method, the proposed method for determination of dissolved P exhibited great advantages such as shorter experiment time, lower limit of detection and higher sample throughput.     

Enhancement of ruthenium determination by inductively coupled plasma/atomic emission spectrometry by addition of periodic acid

A sensitive method for the determination of ruthenium involving the formation of volatile species in solution and subsequent nebulization for inductively coupled plasma/atomic emission spectrometry is proposed. The sensitivity of the determination of ruthenium was increased by a factor of 70 with the addition of 1×10^?2 M periodic acid as an oxidizing agent. The detection limit was 5 ng ml^?1 of ruthenium and the calibration was linear over the range 0.01–0.5 μg ml^?1 of ruthenium. Serious interferences were not found except from reducing agents.     

Dispersive liquid–liquid microextraction combined with flow injection inductively coupled plasma mass spectrometry for simultaneous determination of cadmium, lead and bismuth in water samples

Dispersive liquid–liquid microextraction (DLLME) was combined with flow injection inductively coupled plasma mass spectrometry for simultaneous determination of cadmium, lead and bismuth in water samples. The metal elements were complexed with sodium diethyldithiocarbamate, and then the complexes were extracted into carbon tetrachloride by using DLLME. Under the optimized conditions, the enrichment factors for Cd, Pb and Bi are 460, 900 and 645 in 5 mL of a spiked water sample, respectively. The calibration graphs for the three metals are linear in the range of concentrations from <10 ng L^?1 to 1,000 ng L^?1. The detection limits are 0.5 ng L^?1, 1.6 ng L^?1 and 4.7 ng L^?1, respectively. The relative standard deviations for ten replicate measurements of 50 ng L^?1 cadmium, lead and bismuth are 2.6%, 6.7%, and 4.9%, respectively, and the relative recoveries in various water samples at a spiking level of 50 ng L^?1 range from 83.6% to 107.0%.