METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2024
·Vol. 55
·期 2
·772-781
·
IF 2.4
Tian Qinghua,He Zhiqiang,Xu Zhipeng,Li Dong,Guo Xueyi
High-purity tellurium is a supporting material for contemporary high-tech industries. Zone refining is commonly used as a reliable final purification step to achieve higher purity levels of tellurium. However, the removal of Selenium (Se)—the most troublesome impurity in tellurium often occurring in quite high amounts—stays as the challenge during zone refining, due to its very unfavorable distribution coefficient. In addition, there is an important factor, essential to predict the zone refining efficiency (required number of passes), which is still seldom explored. Therefore, in the present work, the effect of different number of passes on the purification effect of tellurium was investigated by using 4N tellurium as raw material. Firstly, the possibility of removing vaporized Se through introducing an reductive gas flux was studied by testing initial concentrations of Se (13 ppm) and undergoing different process parameters. The experimental results showed that when the number of passes was 3, the impurity removal rate was low and the purification effect was poor; when the number of zone refining reached 9, the removal rate of most impurities in tellurium reached 100 pct, the removal rate of impurity Se reached 80.15 pct, and the total removal rate reached 89.49 pct, and the purity of tellurium ingot was 5N7.
研究领域:
材料科学
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冶金学
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半导体技术
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DOI
高影响因子
CURRENT ORGANIC SYNTHESIS
·
2025
·Vol. 22
·期 5
·614-619
·
IF 2.5
Dejun Zhou,Keyang Wang,Yuying Zhang,Xiaoyue Liu,Xiaoxia Mao
BackgroundTimolol maleate is clinically used for the treatment of hypertension, angina pectoris, tachycardia, and glaucoma.ObjectiveThe aim of this study was to enhance the safe use of timolol maleate and investigate a synthesis method for 3-S-timolol, a newly identified impurity in timolol API (Active Pharmaceutical Ingredients).Methods(S)-3-(tert-butylamino)propane-1,2-diol (1) was used as a raw material. 3-S-timolol maleate (7) was synthesized through a five-step reaction. Overall yield was 57.7%, with a purity of 98%.ResultsThe structure of the target compound was confirmed via analysis of its 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, and high-resolution mass spectrometry spectra.ConclusionThe synthesis method was straightforward and yielded a high-purity product suitable for use as a reference in the analysis and identification of timolol maleate-related substances.
研究领域:
药物化学
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分析化学
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药物质控
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有机合成
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杂质研究
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药物代谢
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DOI
PubMed
高影响因子
JOURNAL OF AOAC INTERNATIONAL
·
2019
·Vol. 100
·期 4
·1029-1037
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IF 1.201
Zou Liang,Sun Lili,Zhang Hui,Hui Wenkai,Zou Qiaogen,Zhu Zheying
The characterization of process-related impurities and degradation products of safinamide mesilate (SAFM) in bulk drug and a stability-indicating HPLC method for the separation and quantification of all the impurities were investigated. Four process-related impurities (Imp-B, Imp-C, Imp-D, and Imp-E) were found in the SAFM bulk drug. Five degradation products (Imp-A, Imp-C, Imp-D, Imp-E, and Imp-F) were observed in SAFM under oxidative conditions. Imp-C, Imp-D, and Imp-E were also degradation products and process-related impurities. Remarkably, one new compound, identified as (S)-2-[4-(3-fluoro-benzyloxy) benzamido] propanamide (i.e., Imp-D), is being reported here as an impurity for the first time. Furthermore, the structures of the aforementioned impurities were characterized and confirmed via IR, NMR, and MS techniques, and the most probable formation mechanisms of all impurities proposed according to the synthesis route. Optimum separation was achieved on an Inertsil ODS-3 column (250 × 4.6 mm, 5 μm), using 0.1% formic acid in water (pH adjusted to 5.0) and acetonitrile as the mobile phase in gradient mode. The proposed method was found to be stability-indicating, precise, linear, accurate, sensitive, and robust for the quantitation of SAFM and its process-related substances, including its degradation products.
研究领域:
药物化学
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分析化学
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产品关联
DOI
PubMed
高影响因子
Current Pharmaceutical Analysis
·
2021
·Vol. 17
·期 7
·873-884
·
IF 0.89
Xia Yun-Yan,Zou Qiao-Gen,Yang Yu-Fei,Sun Qian,Han Cheng-Qun
Background: High-Performance Liquid Chromatography (HPLC) method has been used to detect related impurities of perampanel. However, the detection of impurities is incomplete, and the limits of quantification and detection are high. A sensitive, reliable method is badly needed to be
developed and applied for impurity detection of perampanel bulk drug. Objective: Methodologies utilising HPLC and Gas Chromatography (GC) were established and validated for quantitative determination of perampanel and its related impurities (a total of 10 impurities including 2 genotoxic
impurities). Methods: The separation was achieved on a Dikma Diamonsil C18 column (250 mm 4.6 mm, 5 μm) with the mobile phase of 0.01 mol/L potassium dihydrogen phosphate solution (A) and acetonitrile (B) in gradient elution mode. The compound 2-bromopropane was determined on an Agilent
DB-624 column (0.32 mm 30 m, 1.8 μm) by electron capture detector (μ-ECD) with split injection ratio of 1:5 and proper gradient temperature program. Results: Both HPLC and GC methods were established and validated to be sensitive, accurate and robust according to the International
Council for Harmonization (ICH) guidelines. The methods developed were linear in the selected concentration range (R2≥0.9944). The average recovery of all impurities was between 92.6% and 103.3%. The possible production mechanism of impurities during the synthesis
and degradation processes of perampanel bulk drug was also discussed. Five impurities were analyzed by liquid chromatography–mass spectrometry (LC-MS). Moreover, two of them were simultaneously characterized by LC-MS, IR and NMR. Conclusion: The HPLC and GC methods were developed
and optimized, which could be applied for quantitative detection of the impurities, and further stability study of perampanel.
研究领域:
药物分析
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分析化学
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药学
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DOI
高影响因子
Journal of Chromatography Open
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2025
·
IF 3.2
Yan-nan Zan,Yu Chen,Fei Xie,Shao-hua Shang,Ning Chen,Yi-mei Ding
An efficient high-performance liquid chromatography (HPLC) method was established to detect acylated impurities in triptorelin acetate microspheres for injection. Additionally, HPLC coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS) was employed to identify the types of acylated impurities. In HPLC, the separation of triptorelin and its acylated impurities was achieved on a Welch Ultimate XB-C18 column (250 mm × 4 mm, 5 μm). The mobile phase consisted of a 20 mmol·L -1 aqueous solution of ammonium acetate (pH 6.9) and acetonitrile, delivered in a gradient elution mode with a flow rate of 0.5 mL min -1 . The detection wavelength was set at 210 nm. For the HPLC-QTOF-MS method, the aforementioned HPLC conditions were utilized, and the mass spectrometer employed an electrospray ionization (ESI) ion source in positive ion mode. The scanning range spanned from 100 to 2000 m/z . The carrier gas was N 2 , with an atomization gas flow rate of 3 L·min -1 . The interface voltage was maintained at 4.5 kV, the desolvation temperature at 250 °C, and the drying gas flow rate at 15 L·min -1 . Additionally, the heating block temperature was set at 400 °C, and the interface temperature at 350 °C. Results Using this method, 14 types of acylated impurities in triptorelin were identified, further confirming that the acylation site of triptorelin is the serine alcohol hydroxyl group. Conclusion Both the HPLC and HPLC-QTOF-MS methods can be effectively utilized for routine quality control analysis of triptorelin acetate microspheres for injection.
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高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2024
·Vol. 55
·期 6
·5221-5234
·
IF 2.4
Sun Hu,You Mengyu,Hou Yanrui,Luo Jun,Rao Mingjun,Han Guihong,Li Guanghui
The mainstream oxidative roasting method is facing challenges in processing low-grade molybdenite (MoS 2 ) concentrates, calling for deep understandings toward the behaviors of impurities. This study took pure minerals and reagents as the objects and conducted elaborate experiments and theoretical calculations into the formations of molybdates and their influences on MoS 2 oxidation. The emphasis are on the reactions under local O 2 -absent conditions and the sintering of MoS 2 caused by molybdates of Ca, Fe, Cu, or Pb. It was found that molybdates could directly form from MoO 2 or MoS 2 without O 2 at 600 °C to 650 °C, due to the promotion of reactivity and reducibility of MoO 2 when combining with impurity metals. The produced molybdates would lower the melting point, dissolve in liquid MoO 3 , and migrate to oxidation interface to form a sintering layer that inhibits O 2 diffusion. Overall, this study has discovered new pathways of molybdates formation and new effects of segregation on the sintering and established evolution patterns of bulk MoS 2 concentrate during roasting, which may be significant complements to the fundamentals of classical molybdenum metallurgy.
研究领域:
冶金学
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材料科学
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产品关联
DOI
高影响因子
Minerals
·
2021
·Vol. 11
·期 1
·61
·
IF 2.644
Wenjie Zhang,Xian Xie,Xiong Tong,Yunpeng Du,Qiang Song,Dongxia Feng
Solvent extraction is the most widely used method for separation and purification of rare earth elements, and organic extractants such as di(2-ethylhexyl) phosphoric acid (P204) and di(1-methyl-heptyl) methyl phosphonate (P350) are most commonly used for industrial applications. However, the presence of impurity ions in the feed liquid during extraction can easily emulsify the extractant and affect the quality of rare earth products. Aluminum ion is the most common impurity ion in the feed liquid, and it is an important cause of emulsification of the extractant. In this study, the influence of aluminum ion was investigated on the extraction of light rare earth elements by the P204-P350 system in hydrochloric acid medium. The results show that Al3+competes with light rare earths in the extraction process, reducing the overall extraction rate. In addition, the Al3+stripping rate is low and there is continuous accumulation of Al3+in the organic phase during the stripping process, affecting the extraction efficiency and even causing emulsification. The slope method and infrared detection were utilized to explore the formation of an extraction compound of Al3+and the extractant P204-P350 that entered the organic phase as AlCl[(HA)2]2P350(o).Keywords:Al3+;light rare earths;P204;P350;impurity
研究领域:
化学工程
·
材料科学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Mengling Tu,Wen Ma,Jia Chen,Yunxiao Zhu,Yang Liu,Xiaoli Ni,Xianjiang Li
In recent years, imidacloprid, a first generation neonicotinoid pesticide, has attracted considerable attention due to its high detection rate in the environment and food, as well as its detrimental impact on human beings. The identification of structure-related impurities constitutes an essential aspect of pesticide registration and product standard development, and is of paramount importance for exposure risk and safety evaluation. In this study, the analysis of impurities in high-purity imidacloprid material was conducted using a combination of liquid chromatography-high resolution mass spectrometry (Orbitrap) and machine learning platform (SIRIUS + CSI:FingerID). The structure of IMI, as well as the feature fragments, were served as the foundation for decoding the chemical structures of the impurities, and this procedure was guided by the molecular formulas and fragment tree by SIRIUS + CSI:FingerID. Ultimately, 28 impurities were annotated and assigned confidence levels, of which 10 had CAS registry numbers, 5 had PubChem CIDs, and 4 were further verified by three dimension indexes (retention time, ultraviolet spectra and mass spectra) using standards. These impurities have been categorized into three levels (4 in level 1, 12 in level 2a and 12 in level 2b) according to their credibility. This approach was capable of providing accurate molecular formulas and possible structures of impurities, thereby greatly saving the time taken to resolve mass spectra. The elucidated impurity fingerprint can assist in the assessment of the potential health and ecological risks associated with imidacloprid and related impurities.
研究领域:
环境科学
·
农药化学
·
毒理学
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产品关联
DOI
高影响因子
HYDROMETALLURGY
·
2019
·
IF 3.465
Xuexin Chen,Hui Wang,Baijun Yan
In order to recover vanadium from vanadium-bearing black shale efficiently, a hydrometallurgical process is developed in this paper to treat the concentrate beneficiated from stone coal ore, in which the vanadium mainly occurs in the form of Fe 3- x V x O 4 spinel. At the first step, the leaching behaviors of Fe and V from the concentrate by using sulfuric acid solution are investigated in detail. The extraction rates of vanadium and iron could reach 92.5% and 98.5% respectively under the optimum leaching conditions of leaching temperature of 90 °C, sulfuric acid concentration of 25 wt%, leaching time of 90 min, L/S mass ratio of 30 and stirring speed of 600 rpm. Secondly, the iron impurity in the pregnant solution is removed efficiently by the precipitation method with Fe 2 O 3 as nucleating agent. The effect of pH value, the amount of Fe 2 O 3 nucleating agent and the precipitating time on the removal of iron and losing of vanadium are systematically investigated, and thereby >99.7% iron impurity can be removed with the loss rate of vanadium not higher than 2.5%. Finally, vanadium is precipitated from the purified leach solution as ammonium poly-vanadate by adding ammonium sulfate , and then the product of V 2 O 5 is obtained by calcining the ammonium poly-vanadate. The purity of V 2 O 5 powder can reach 92.0% approximately.
研究领域:
冶金学
·
无机化学
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产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 15
·9256-9262
·
IF 4.036
Mengmeng Zhao,Xiaoxia Wu,Zengda Yu,Yunkai Sun,Zhao Liu,Jinqiao Yuan,Hu Liu,Yiping Jin
Avanafil is a phosphodiesterase type 5 inhibitor which is used to treat erectile dysfunction in men. The process-related impurities of avanafil were investigated, and four kinds of impurities in several laboratory batches with a content of 0.29–1.63% were detected by the newly developed gradient ultra-high performance liquid chromatography (UPLC). Based on the synthesis route and UPLC-MS research, the impurities are inferred as Imp-A, Imp-B, Imp-C and Imp-D. The structures of the impurities were inferred from LC-MS studies and confirmed by synthesis, followed by spectroscopic characterization such as NMR and mass spectrometry. Especially, the synthesis of Imp-D is firstly reported. The drug-related substances can be separated well by efficient and selective ultra-high performance liquid chromatography on a Waters ACQUITY HSS C18 (50 × 2.1 mm, particle size 1.8 μm) column at 35 °C, with the mobile phase consisting of ammonium formate (20 mM) and acetonitrile, and the detection at 239 nm with a DAD detector. The method was validated in terms of specificity, linearity, precision, accuracy and sensitivity, and satisfactory results were obtained. The results indicated this developed UPLC method for avanafil and the proposed synthesis mechanism can be used for quality control purposes as required by regulatory agencies to ensure the safety and efficacy of the product.
研究领域:
药物化学
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分析化学
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产品关联
DOI
PubMed
高影响因子
CHROMATOGRAPHIA
·
2022
·Vol. 86
·期 2
·185-197
·
IF 2.213
Lin Xinghua,Hao Gugu,Xu Guobin,Sun Fuzhou,Xin Libo,Wu Shuming,Wang Zhongqing,You Jinsong,Huang Fangfang,Song Xuezhi
An unknown peak with a relative retention time (RRT) of 1.47 was noticed in HPLC chromatograms for related substances of mirabegron extended-release tablets. The level of this unknown peak under the accelerated stability condition for 6 months was as high as 0.19%, which had a trend to exceed the identification threshold of 0.2% from ICH Q3B. The purpose of this study was to identify the RRT 1.47 impurity, and we studied its degradation mechanism to control its content to a lower level. The structure of the RRT 1.47 impurity was identified as a mirabegron dimer bridged by methylene via LC–MS and NMR. Investigation on compatibility of drug-excipients indicated that this impurity formed by Mannich reaction between mirabegron and residual formaldehyde in excipients polyethylene glycol (PEG), polyoxyethylene (PEO). Moreover, the determination of formaldehyde content in excipients further proved this speculation. There was a linear relationship between the amount of formaldehyde and the content of generated dimer impurity within a certain range. The reaction between mirabegron and formaldehyde at different temperatures demonstrated that the higher the temperature, the faster the reaction rate and the higher level of this impurity were generated. To understand the kinetics of the reaction, we calculated the rate of dimerization and also the activation energy of the process based on the stability data. During the development of pharmaceutical formulation on mirabegron or similar structure, appropriate excipients should be selected or the formaldehyde content in excipients could be controlled to avoid such reactions to improve the quality of the product.
研究领域:
药物化学
·
制药工程
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产品关联
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Qiaoling Chen,Litian Lin,Chang Ji,Chang-Kui Duan
The unintentional incorporation of various unknown trace amounts of impurities poses challenges and controversies in identifying luminescent mechanisms of certain systems. A common approach to confirm or exclude the involvement of a certain activation center is to monitor the changes in luminescence by intentionally doping the inferred species into the crystal. Here, an intriguing luminescent phenomenon resulting from the hidden interplay between the dopants and trace impurities, is presented. In alkaline-earth stannate perovskites, near-infrared luminescence is observed. By combining density-functional calculations with the well-designed doping and codoping experimental strategies, the mechanisms behind this anomaly is successfully uncovered. It originates from the stabilization of Cr 3 + by codopants such as Bi and rare-earth (RE) ions, acting as electron donors. The luminescence is almost unobservable when chromium is doped alone, and thus the traditional identification method does't work. This work emphasizes the important role of trace impurity in materials, especially the subtle change of valence state of trace impurity upon doping, which provides enlightening insights and prompts reassessments of numerous reported anomalous luminescent phenomena.
研究领域:
材料科学
·
光学
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DOI
高影响因子
危险品化学品经营许可证（带存储）