Analytical Methods
·
2025
·
IF 2.6
Yong-Hai Yuan,Feng Yang,Qiu Zhang,Qinghong Xu,Meilan Wen
This study focuses on comparing the performance of pneumatic nebulization (PN), hydride generation (HG), and photochemical vapor generation (PVG) sampling modes coupled with inductively coupled plasma mass spectrometry (ICP-MS) for the determination of Se and Te in geological samples. ICP-MS operating parameters for each sampling mode, such as RF power, flow rate of collision gas, and sampling depth, were optimized. The introduction efficiency of Se and Te in PN mode was about 4.71% and 4.58% respectively, with the best reproducibility. HG mode had the highest introduction efficiency (57.01% for Se and 53.02% for Te), but the poorest reproducibility. PVG mode showed a good balance between efficiency and reproducibility, with introduction efficiencies of 45.38% for Se and 38.84% for Te, and lower limits of detection (LODs) of 0.001 μg·L-¹ for both Se and Te. Analysis of 14 geological certified reference materials (CRMs) indicated that for samples with Se > 0.1 μg·g-¹ and Te > 0.05 μg·g-¹, both PN and PVG sampling modes can obtain satisfactory results, and PN mode is more convenient. For samples with Se ≤ 0.1 μg·g-¹ and Te ≤ 0.05 μg·g-¹, HG or PVG sampling modes are recommended after enrichment pretreatment. This research provides a more precise and reliable method selection basis for analyzing Se and Te in geological samples at different concentration levels.
研究领域:
分析化学
·
地球化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2020
·
IF 4.302
Zhao-Feng Yuan,Williamson Gustave,Raju Sekar,Jonathan Bridge,Jia-Yue Wang,Wei-Jia Feng,Bin Guo,Zheng Chen
The redox-sensitive elements, such as iron, manganese, sulfur, phosphorus, and arsenic, shift their speciation every millimeter (mm) across the soil-water interface in the flooded soil environments. Monitoring of element speciation at this high-resolution (HR) within the SWI is still difficult. The key challenge lies in obtaining sufficient porewater samples at specific locations along the soil gradient for downstream analysis. Here with an optimized inductively coupled plasma mass spectrometry (ICP-MS) method and a HR porewater sampler, we demonstrate mm-scale element profiles mapping across the SWI in paddy soils. High-concentrations of iron and manganese (> 10 mg/L) were measured by ICP-MS in an extended dynamic range mode to avoid signal overflow. The iron profile along the SWI generated by the ICP-MS method showed no significant difference ( p < 0.05) compared to that measured independently using a colorimetric method. Furthermore, four arsenic (arsenite, arsenate, monomethylarsonic and dimethylarsinic acid), two phosphorus (phosphite and phosphate) and two sulfur (sulfide and sulfate) species were separated in 10 min by ion chromatography -ICP-MS with the NH 4 HCO 3 mobile phase. We verified the technique using paddy soils collected from the field, and present the mm-scale profiles of iron, manganese, and arsenic, phosphorus, sulfur species (relative standard deviation < 8%). The technique developed in this study will significantly promote the measurement throughput in limited samples (e.g. 100 μL) collected by HR samplers, which would greatly facilitate redox-sensitive elements biogeochemical cycling in saturated soils.
研究领域:
土壤学
·
环境科学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 15
·2419-2425
·
IF 3.741
Feng Zhongmin,Guo Tingting,Jiang Zhiwen,Sun Ting
We have investigated the possibility of sampling ammonium ion using the diffusive-gradients-in-thin-films technique (DGT) by introducing a novel binding agent that is based on micro-sized zeolite. The performance of zeolite-DGT was characterized by measurement of the following parameters: (1) the diffusion coefficient of ammonium ion in hydrogel; (2) the adsorption rate of ammonium ion by the zeolite binding gel; (3) the elution efficiency, and (4) the effects of pH, ionic strength and interfering ions on DGT. The method was validated by studying the uptake of ammonium ion from in freshwaters by zeolite gels which was found to be fast enough to meet the requirements of DGT. The concentrations determined via DGT agreed well with the concentrations determined in bulk solutions. Sampling of ammonium ion using zeolite-DGT was consistent over the pH 3 to 8 range and the 0.001 to 10 mM ionic strength range. The method also performs predictably in natural waters containing various metal ions. The technique is considered to be a viable passive tool for sampling ammonium from aqueous solutions.
Schematic representation of the principle of DGT and the determination of mass accumulated on the binding gel.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2024
·Vol. 16
·期 46
·7955-7964
·
IF 2.7
Si-si Liu,Shi-bao Chen,Yu-bo Yue,Xiao-hao Li,Chi Zhang,Guang-Guo Ying,Chang-Er Chen
Due to their wide applications, occurrence and “PFAS-like” environmental behaviors, ionic liquids (ILs) represent a new challenge for the environmental monitoring community, who require robust analytical methods that can determine accurately and efficiently their environmentally relevant concentrations. A new passive sampling method based on the diffusive gradients in thin films (DGT) technique was developed for the measurement of imidazole-based ILs in waters using a mixed-mode cation exchange (MCX) resin as the adsorbent. The selected binding gel had a high binding capacity (>170 μg per disc) for ILs. Diffusion coefficients measured using a diffusion cell correlated well with alkyl chain lengths (r2 = 0.95) and retention times (r2 = 0.88), providing a simple and rapid prediction approach for other ILs. The assembled MCX-DGT sampler exhibited a linear accumulation for at least 120 h. MCX-DGT also showed good performance under typical freshwater conditions (pH 5–8, ionic strength 0.001–0.01 M, and humic acid 0–5 mg L−1), while still being problematic for aquatic conditions with higher ionic strength (>0.1 M) or DOM (>10 mg L−1). Laboratory deployment (for up to 3 days) in spiked natural freshwater (SNW) resulted in linear mass uptakes for the short-chain ILs (C2–C8), and their DGT-measured concentrations agreed well with solution concentrations. However, MCX-DGT significantly overestimated the concentrations of the long-chain ILs (C10–C12) when deployed in SNW for one day or more, which is attributed to the strong competitive adsorption of the long-chain ILs by natural organic matter. In situ field evaluation along with grab sampling found no target ILs in a wastewater treatment plant and its receiving river, implying that these new chemicals might not be widely used in South China now. This is the first report on the DGT technique for ILs and might provide an effective tool for monitoring short chain length ILs in the aquatic environment in the near future.
研究领域:
环境科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Xiuhong Liao,Zhaochu Hu,Wen Zhang,Yantong Feng,Tao Luo,Zaicong Wang,Ming Li,Keqing Zong,Yongsheng Liu,Shenghong Hu
Using boron as a test analyte, laser ablation (LA) solution sampling multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) is proposed and validated as a fast method for isotopic analysis in natural liquids and digested samples without any prior purification process. We demonstrated that the solution reference standard can be used as a bracketing standard for in situ δ11B analysis in solids. Based on a sensitivity enhancement of 8- to 9-fold, all testing solutions were diluted in a 5% (v/v) NH3·H2O instead of classical 2% (v/v) HNO3. With a discrete and minimal sample solvent loading by the LA sampling strategy, it produces nearly “dry” plasma conditions that tolerate the sample matrix remarkably. The memory effect, one of the most difficult challenges in boron analysis, was dramatically eliminated with only 15 s wash time; thus, each analysis took less than 100 s. No significant matrix effects were observed for varying 50–100% boron concentrations in the samples and varying 20–60% NH3·H2O matrix used for the dilution, as well as for samples doped with a 1/100 synthetic seawater matrix. The external precision of δ11B measurements in NIST 951a was ± 0.30‰ (2SD). Good agreement with the values described in literature studies was achieved for δ11B measurements in eight geological reference materials, with precisions between 0.4 and 0.7‰ (2SD), confirming the accuracy of the proposed method. The proposed method offers advantages of simple sample preparation, fast analysis, and little use of chemical reagents.
研究领域:
地球化学
·
分析化学
✓ 已验证
DOI
高影响因子
Environmental Technology & Innovation
·
2024
·
IF 6.7
Shengming Cheng,Cailin Li,Sisi Liu,Hongyan Zou,Guang-Guo Ying,Chang-Er Chen
To enhance the detection of the escalating presence of per- and poly-fluoroalkyl substances (PFAS) in aquatic environments, the development of innovative sampling techniques becomes imperative. This study focuses on testing a novel passive sampler for in situ sampling of PFAS, employing a ceramic filter tube (CFT) coupled with a hydrogel containing adsorbent-imbedded weak anion exchange resin (WAX) in rod format. The WAX gel rod demonstrated swift binding of the targeted PFAS and potential reusability at least five times. The integrated passive sampler, CFT-WAX, exhibited a linear accumulation pattern for five PFAS in the lab, resulting in a lower diffusive coefficient through the CFT wall than other samplers due to the thicker wall. Notably, variations in pH, ionic strength, and dissolved organic matter did not significantly influence the performance of CFT-WAX. Field deployment in a wastewater treatment plant (WWTP) demonstrated its reasonable performance compared to traditional grab sampling. Though further optimisation in the future is warranted, the findings of this study underscore the efficacy of the developed CFT-WAX passive sampler as a promising tool for in-situ sampling PFAS in aquatic environments.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2016
·
IF 5.886
Zhongmin Feng,Peng Zhu,Hongtao Fan,Shanshan Piao,Liang Xu,Ting Sun
We evaluated the possibility of sampling dissolved orthophosphate using the diffusive gradient in thin films (DGT) technique with a phosphate ion-imprinted polymer (PIP)-based adsorbent and assessed the effect of biofilm on the DGT measurement. The composition of biofilm formed on the DGT surface was analyzed, and the effect of biofouling on the diffusion coefficient of the analyte was investigated. The corrected diffusion coefficient for the biofouled DGT was estimated and used for the calculation of the DGT equation. PIP-binding gels had a higher adsorption affinity for orthophosphate than for the other anions, indicating its selectivity for orthophosphate. The concentrations predicted via DGT agreed well with the concentrations determined in the bulk solutions. Sampling of orthophosphate using PIP-DGT was consistent over a pH range of 3–9 and ionic strength range of 0.01–10 000 μM. Other P compounds cannot be measured using the PIP-DGT technique. The diffusion coefficient of the orthophosphate linearly decreased with increasing thickness of the biofilm. This sampling method performed predictably in freshwater when the biofilm was not formed or when value for the biofilm interference was reduced by using the corrected diffusion coefficient.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Yi-Tao Zou,Zhou Fang,Yuan Li,Runmei Wang,Hao Zhang,Kevin C. Jones,Xin-Yi Cui,Xin-Yao Shi,Daixia Yin,Chao Li,Zhao-Dong Liu,Lena Q. Ma,Jun Luo
Widespread use of organophosphorus flame retardants (OPFRs) and their ubiquity in water results in the need for a robust and reliable monitoring technique to better understand their fate and environmental impact. In situ passive sampling using the diffusive gradients in thin-films (DGT) technique provides time-integrated data and is developed for measuring OPFRs here. Ultrasonic extraction of binding gels in methanol provided reliable recoveries for all tested OPFRs. Diffusion coefficients of TCEP, TCPP, TDCPP, TPrP, TBP, and TBEP in the agarose diffusive gel (25 °C) were obtained. The capacity of an HLB binding gel for OPFRs was >115 μg per disc, and the binding performance did not deteriorate with time up to 131 days. DGT performance is independent of typical environmental ranges of pH (3.12–9.71), ionic strength (0.1–500 mmol L–1), and dissolved organic matter (0–20 mg L–1), and also of diffusive layer thickness (0.64–2.14 mm) and deployment time (3–168 h). Negligible competition effects between OPFRs was found. DGT-measured concentrations of OPFRs in a wastewater treatment plant (WWTP) effluent (12–16 days) were comparable to those obtained by grab sampling, further verifying DGT’s reliability for measuring OPFRs in waters.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSYSTEMS ENGINEERING
·
2019
·
IF 2.983
Zun Man,Xiaorong Dai,Li Rong,Xianwang Kong,Shihao Ying,Yicong Xin,Dezhao Liu
The selection of sampling bags for odour measurement by olfactometry is critical and challenging since the loss of odorants during storage and transportation is usually high. However, there are no recommendations or limitations on the storage time for the standard Triangle odour bag method used in China. In order to optimise the selection of sampling bags, selected types of sampling bags (Fluode, BOPET, FEP and Tedlar) were tested and compared by using selected key odorants (dimethyl sulphide, 2-butanone, 2,3-butanedione, 4-methylphenol, indole , skatole, acetic acid, propanoic acid, butyric acid , valeric acid and hexanoic acid). The concentrations of key odorants were detected by PTR-MS. Firstly, background contamination was tested, with total amount of background pollutants produced by Tedlar being significantly higher than the other three types of sampling bags, while FEP and BOPET had less background contaminants. Secondly, recovery tests showed that the SOAV (sum of odour activity values) recoveries after 24 h of storage of Fluode, Tedlar, FEP and BOPET were 19.5%, 24.2%, 47.7% and 27.7%, respectively. FEP had better recovery than others, especially for the storage of 4-methylphenol (~55% recovery after 48 h), which is one of the key odorants emitted from intensive pig production. Finally, the recovery tests for 2,3-butanedione were performed under various conditions and results indicated that the storage of 2,3-butanedione in sampling bags depends on bag type (e.g. single bags or double bags), initial concentration level (10 ppbv, 100 ppbv or 1000 ppbv), the inner surface area-to-volume ratio and light condition (dark, natural light or LED light).
研究领域:
环境科学
·
动物生产学
✓ 已验证
DOI
高影响因子
BIOMEDICAL MICRODEVICES
·
2019
·Vol. 21
·期 3
·1-10
·
IF 2.327
Chen Jianmin,Wang Meixia,Ye Yaling,Yang Zhouyan,Ruan Zhipeng,Jin Nan
Microneedle (MN) patch has been used for collecting dermal interstitial fluid (ISF) containing biomarkers from patients with safety, pain-free and easy-to-use manner. However, long sampling time for biomarkers analysis still poses a significant challenge. Here, we describe a new sponge-forming MN patch consisting of polyvinyl formal (PVF) for rapidly extracting ISF from skin. Owing to the supreme water affinity of PVF, this MN patch can extract 1.6 mg ISF in 1 min without the assistance of extra devices, which remarkably facilitates timely analysis. The MN patch had preserved structural integrity in the swelling hydrated state without leaving residues in skin after usage, and the treated skin recovered within 8 h. More importantly, the extracted ISF can be efficiently recovered from the MN patch by simple centrifugation for the subsequent offline analysis of biomarkers such as glucose and cholesterol. Our results reveal that the new sponge-forming MN patch holds considerable promise for minimally invasive sampling ISF for biomarkers detection in real-life situations.
研究领域:
生物医学工程
·
分析化学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Xiaoming Chen,Tao Wang,Leimiao Lin,Fangjie Wo,Yaqin Liu,Xiao Liang,Hui Ye,Jianmin Wu
Nanostructured semiconductors are one of the most potent candidates for matrix-free laser desorption/ionization mass spectrometric (LDI-MS) analysis of low-molecular-weight molecules. Herein, the enhanced photoinduced electron transfer and LDI on the tip of a vertical silicon nanowire (SiNW) array were investigated. Theoretical simulation and LDI detection of indigo and isatin molecules in negative ion mode revealed that the electric field can be enhanced on the tip end of SiNWs, thereby promoting the energy and electron transfer to the analytes adsorbed on the tip of SiNWs. On the basis of this finding, a tip-contact sampling method coupled with LDI-MS detection was established. In this strategy, the tip of SiNWs can be regarded as microextraction heads for the sampling of molecules when they come in contact with analytes. Impression of skin, tissue, and pericarp on the vertical SiNW array can effectively transfer endogenous metabolites or exogenous substances onto the tip. Upon laser irradiation, the adsorbed molecules on the SiNW tip can be efficiently ionized and detected in negative ion mode because of the tip-enhanced electron transfer and LDI effect. We believe this work may significantly expand the application of LDI-MS in various fields.
研究领域:
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Zhihang Yu,Wenqiang Tong,Jiaming Shi,Siyuan Chen,Lingling Shui,Huaying Chen,Liuyong Shi,Jing Jin,Yonggang Zhu
Microelectrodes have transformed our understanding of spatiotemporal responses to electrical stimulation. However, biological signals are often molecular, complicating the capture of intricate chemical signals. The microfluidic chip developed in this paper accurately measures droplet volume by using impedance analysis. The utilization of droplet volume as a feedback signal for precise microsampling pressure control ensures that microsampling remains unaffected by droplet volume influence. Once the microsampling is complete, chemiluminescence detection enables high temporal resolution and continuous and sensitive monitoring of chemical information within the droplets. Experimental verification shows that the chip can avoid volume influence through impedance feedback, achieving consistent and stable microampling at the nanoliter level (0–3 nL). In just 0.3 s, it can perform sensitive chemiluminescence detection of H2O2 and glucose within droplets. The linear detection ranges for these analytes are 10–50,000 and 20–600 μM, respectively, with the limit of detection being 0.648 and 0.334 μM. The significance of this chip lies in its ability to reveal changes in both electrical and chemical signals during transient biological processes. Its potential applications are numerous, encompassing a wide range of emerging areas such as single-cell analysis, cell communication, and cellular immunity.
研究领域:
生物医学工程
·
分析化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）