MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Xianjiang Li,Wei Zhang,Shukun Zhou,Xiao Li,Mengling Tu,Yunxiao Zhu,Qinghe Zhang,Hongmei Li
Thiamethoxam (TMX) belongs to the second-generation neonicotinoid pesticide, which is among the most common residual in food commodities. To guarantee accurate quantification and traceability of results in food samples, certified reference materials (CRMs) are indispensable benchmark. TMX was characterized and its purity value was assessed by two independent measurement methods including mass balance (MB) and quantitative nuclear magnetic resonance spectroscopy (qNMR). Its mass fraction was 997.0 mg/g and 991.7 mg/g in MB and qNMR, respectively. Eventually, a purity of 994 mg/g with standard uncertainty of 3 mg/g ( k = 2) was assigned to TMX.
研究领域:
食品科学
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分析化学
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产品关联
DOI
高影响因子
Journal of Analysis and Testing
·
2024
·Vol. 8
·期 1
·1-8
·
IF 5.5
Tu Mengling,Zhang Wei,Zhu Yunxiao,Ma Wen,Li Xiao,Zhou Shukun,Li Hongmei,Li Xianjiang
Thiacloprid is the first-generation neonicotinoid insecticide, which is widely used in modern agriculture. Reference materials are essential for sound measurement and traceability of results in chemical analysis. Pure thiacloprid was comprehensively assessed by two orthonormal methods: mass balance (MB) and quantitative nuclear magnetic resonance spectroscopy (qNMR). From MB, its mass fraction value was 998.4 mg/g with the subtraction of structurally related impurities (99.87%), inorganic impurities (0.006 mg/g), water (0.33 mg/g), and volatile organic solvent (0 mg/g). To guarantee sufficient separation of structurally related purity, peak purity of thiacloprid was evaluated by five points of UV spectra. From the qNMR of hydrogen, its mass fraction value was 995.7 mg/g which was traced to the internal standard (methyl sulfone). Finally, the certified value was assigned to 997 mg/g, together with an expanded uncertainty of 3 mg/g ( k = 2). This high-purity thiacloprid can be applied to routine monitoring in agriculture and the food fields.
研究领域:
分析化学
·
农业科学
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食品科学
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产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2023
·Vol. 415
·期 17
·3375-3384
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IF 4.3
Liu Si,Lu Boling,Peng Zijuan,Liu Chunyu,Liu Yuhui,Jiao Hui,Wu Dan,Li Penghui,Zhao Xingchen,Song Shanjun
In organic purity assessment, chromatography separation with a suitable detector is required. Diode array detection (DAD) has been a widely used technique for high-performance liquid chromatography (HPLC) analyses, but its application is limited to compounds with sufficient UV chromophores. Charged aerosol detector (CAD), as a mass-dependent detector, is advantageous for providing a nearly uniform response for analytes, regardless of their structures. In this study, 11 non-volatile compounds with/without UV chromophores were analyzed by CAD using continuous direct injection mode. The RSDs of CAD responses were within 17%. For saccharides and bisphenols, especially, the RSDs were lower ( 2.12% and 8.14%, respectively). Since bisphenols exist in UV chromophores, their HPLC–DAD responses were studied and compared with CAD responses, with CAD showing a more uniform response. Besides, the key parameters of HPLC-CAD were optimized and the developed method was verified using a Certified Reference Material (CRM, dulcitol, GBW06144). The area normalization result of dulcitol measured by HPLC-CAD was 99.89% ± 0.02% ( n = 6), consistent with the certified value of 99.8% ± 0.2% ( k = 2). The result of this work indicated that the HPLC-CAD method could be a good complementary tool to traditional techniques for the purity assessment of organic compounds, especially for compounds lacking UV chromophores. Graphical Abstract
研究领域:
分析化学
·
药物分析
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DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Huan Yao,Ting Huang,Zhifang Li,Huaxin Wu,Xueyao Li,Hua Tang,Fuhai Su,Xinliang Jin,Wei Zhang
Purity assessment is critical for the quality control of active pharmaceutical ingredients (APIs). However, there is a lack of rapid and accurate purity assessment methods that operate independently of target-specific certified reference materials (CRMs). Herein, we proposed a traceable quantification method, named SFC-ISC-qNMR, for purity assessment and quantitative determination of low-purity APIs, which was accomplished by tracing the test solution to the reference solution via supercritical fluid chromatography (SFC) collection with internal standard-correction (ISC), followed by an SI-traceable quantitative nuclear magnetic resonance (qNMR) analysis of the reference solution (SI = International System of Units). Digitoxin, a widely used cardiac glycoside in the treatment of heart failure and arrhythmias, was used as a model compound. By employing a mobile phase of supercritical CO2 modified with 24%–26% methanol, digitoxin with a purity exceeding 99.87% was isolated and collected. A national CRM of ethyl para-hydroxybenzoate was used as the IS for digitoxin. The SFC-ISC reference solution can be prepared in 15 min without the need for precise weighing, simply by reconstitution of the SFC collected high-purity analyte in deuterated methanol containing IS. The feasibility and reliability of the SFC-ISC-qNMR method were exhibited through the quantitative determination of digitoxin in chemical mixtures. The purity of a commercially available digitoxin reagent was determined to be 94.17% ± 0.15%, which was consistent with high-resolution qNMR analysis. The contents of spiked digitoxin in a digoxin analytical standard were measured at 1.06%, 1.37%, 2.39%, and 4.43%, respectively, showing high consistency with the gravimetric value with a bias less than 0.13%. In contrast, direct qNMR with deconvolution and HPLC analysis failed to provide accurate measurements. These results highlight the applicability of the SFC-ISC-qNMR method for drug evaluation and research, demonstrating its significant potential for the purity assessment of APIs.
研究领域:
分析化学
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药物分析
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色谱分析
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核磁共振（NMR）
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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）