SENSORS
·
2023
·Vol. 23
·期 3
·1362
·
IF 3.9
Haozhi Zhang,Hao Jia,Weiwen Feng,Zao Ni,Pengcheng Xu,Xinxin Li
Ultra-responsive single-crystal silicon MEMS thermopiles for differential thermal analysis (DTA) are developed. Facilitated by a unique “microholes interetch and sealing (MIS)” technique, pairs of suspended thermopiles are batch fabricated in a differential form, with high-density (54 pairs) n-type/p-type single-crystal silicon thermocouples integrated within each thermopile (sample area ~0.045 mm2). The fabricated MEMS thermopile sensors exhibit outstanding power responsivity of 99.5 V/W and temperature responsivity of 27.8 mV/°C, which are more than 4 times higher than those reported for material thermal analysis. The high-responsivity MEMS DTA chips allow us to accurately measure the indium melting point at different heating rates of ~1–100 °C/s. We also perform DTA measurement of the dehydration process of CuSO4·5H2O and the crystals show three stages of losing water of crystallization before becoming anhydrous copper sulfate salt. Our high-performance, cost-effective MEMS sensing chips hold promise for rapid and accurate DTA characterization for a wide range of applications.Keywords:MEMS thermopile;differential thermal analysis;DTA;single-crystal silicon thermocouples;MIS process
研究领域:
材料科学
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微机电系统
·
热分析技术
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Jianhua Zu,Jingjie Diao,Gang Han,Wenjuan Xue,Xiaohan Pan,Mingjie Jin,Qing Tang
In this study, a carboxyl-functionalized covalent organic framework (COF) rich in nitrogen (N) and oxygen (O) functional groups was prepared and characterized, which provided a new opportunity for the efficient and rapid treatment of radioactive contamination in nuclear wastewater. The synthesis of the COF (Tp-DTA) was constructed using 1,3,5-triformylphloroglucinol (TFP) and 2,5-diaminoterephthalic acid (DTA), providing a large specific surface area, mesoporous pore, and abundant coordination sites with high adsorption capacity and exceptional affinity for Sr 2+ . Batch adsorption experiments exhibited that Tp-DTA achieved a maximum adsorption capacity of 145.4 mg/g for Sr 2+ in alkaline solutions, reaching adsorption equilibrium within 60 min. Tp-DTA exhibited rapid kinetics for 90 Sr, with the amounts of 90 Sr removed more than 95% within 3 min. In the presence of coexisting ions (Na + , K + , Cs + , Mg 2+ , and Ca 2+ ), Tp-DTA displayed excellent preferential selectivity for Sr 2+ and high removal efficiency. Even in simulated groundwater containing multiple complex ions, Tp-DTA demonstrated a strong affinity for Sr 2+ and showed practical applicability with a nearly 100% removal efficiency for 90 Sr. XPS and FTIR characterizations confirmed that the adsorption mechanism of Sr 2+ involved chelation exchange between the carboxyl groups of Tp-DTA and Sr 2+ in the solution. Furthermore, the desorption efficiency of HCl (>0.01 mol/L) can reach 95% and five cyclic desorption-adsorption experiments demonstrated the reusability of Tp-DTA, endowing the carboxyl-functional COF with great potential in the treatment of 90 Sr-contaminated radioactive wastewater and environmental remediation.
研究领域:
环境科学
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材料科学
·
放射化学
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产品关联
DOI
高影响因子
EXPERT SYSTEMS WITH APPLICATIONS
·
2023
·
IF 8.5
Guanxing Chen,Haohuai He,Lu Zhao,Qiujie Lv,Calvin Yu-Chian Chen
The COVID-19 pandemic’s profound impact on global health and the economy underscores the need for new computational strategies to rapidly identify potential antiviral drugs against emerging and re-emerging infectious diseases. AI-based drug repurposing methods have the potential to significantly shorten the drug discovery process, rendering them a crucial and efficacious approach for screening anti-SARS-CoV-2 compounds. In this paper, we proposed GINCM-DTA, an AI-based graph isomorphism network with protein contact map representation for drug–target affinity (DTA) prediction, and presented the COVID-DTA dataset for SARS-CoV-2-specific drug repurposing. Pre-training GINCM-DTA on large-scale Davis and KIBA datasets achieved state-of-the-art performance, while fine-tuning on the COVID-DTA dataset using transfer learning resulted in a mean square error of 0.026 and concordance index of 0.967. Utilizing the fine-tuned GINCM-DTA model, we predicted DTAs for drugs against SARS-CoV-2 main targets, focusing on key conserved proteins and unmutated spike proteins for virtual screening. We integrated GINCM-DTA predictions with molecular docking simulations to identify five candidates. In vitro assays revealed Hydralazine (5.737 nM) as a potential inhibitor of ACE2 and TMPRSS2, effectively blocking SARS-CoV-2 infection. Moreover, the results highlight the potential of Hydralazine as a broad-spectrum drug candidate, demonstrating its efficacy in obstructing the binding between ACE2 and spike proteins of multiple Omicron variants, including the currently dominant strains BQ.1, BQ.1.1, XBB.1.5, and XBB.1.16. Our method offers a novel computational strategy for COVID-19 antiviral screening and prepares for potential future epidemics incited by emerging viruses.
研究领域:
人工智能
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药物发现
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计算生物学
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病毒学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2017
·
IF 2.236
Siyu Wang,Yini Li,Jie Wang,Shaoxu Wang,Quan Shi,Zhicheng Tan
We found a new way to prove the interaction between the two components in polyaniline (PANI-DTA)/La composites by studying the specific heat. It is firstly found that PANI-DTA has a phase transition peak at −50 °C. The composites (PLa) have no phase transition at −50 °C, so the thermal, magnetic and electrochemical properties are different from PANI-DTA. The heat capacities of the composites are higher than that of PANI-DTA and La complex. the magnetic field dependence of magnetization (M–H) curves of PANI-DTA and PLa-2 exhibit saturation magnetization and a hysteresis loop. The electrochemical performance of the composites are greatly improved compared with PANI-DTA and La complex.
研究领域:
材料科学
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复合材料
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热力学
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电化学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
Metabolites
·
2024
·Vol. 14
·期 3
·142
·
IF 3.4
Yaxin Wang,Chaolu Tan,Yinghao Li,Fengyan Meng,Youwei Du,Shuyu Zhang,Wenxin Jiang,Naijie Feng,Liming Zhao,Dianfeng Zheng
A large number of dead seedlings can occur in saline soils, which seriously affects the large-scale cultivation of rice. This study investigated the effects of plant growth regulators (PGRs) and nitrogen application on seedling growth and salt tolerance (Oryza sativaL.), which is of great significance for agricultural production practices. A conventional rice variety, “Huang Huazhan”, was selected for this study. Non-salt stress treatments included 0% NaCl (CK treatment), CK + 0.05 g N/pot (N treatment), CK + 40 mg·L−15-aminolevulinic acid (5-ALA) (A treatment), and CK + 30 mg·L−1diethylaminoethyl acetate (DTA-6) (D treatment). Salt stress treatments included 0.3% NaCl (S treatment), N + 0.3% NaCl (NS treatment), A + 0.3% NaCl (AS treatment), and D + 0.3% NaCl (DS treatment). When 3 leaves and 1 heart emerged from the soil, plants were sprayed with DTA-6 and 5-ALA, followed by the application of 0.3% NaCl (w/w) to the soil after 24 h. Seedling morphology and photosynthetic indices, as well as carbohydrate metabolism and key enzyme activities, were determined for each treatment. Our results showed that N, A, and D treatments promoted seedling growth, photosynthesis, carbohydrate levels, and the activities of key enzymes involved in carbon metabolism when compared to the CK treatment. The A treatment had the most significant effect, with increases in aboveground dry weight and net photosynthetic rates (Pn) ranging from 17.74% to 41.02% and 3.61% to 32.60%, respectively. Stomatal limiting values (Ls) significantly decreased from 19.17% to 43.02%. Salt stress significantly inhibited seedling growth. NS, AS, and DS treatments alleviated the morphological and physiological damage of salt stress on seedlings when compared to the S treatment. The AS treatment was the most effective in improving seedling morphology, promoting photosynthesis, increasing carbohydrate levels, and key enzyme activities. After AS treatment, increases in aboveground dry weight, net photosynthetic rate, soluble sugar content, total sucrose synthase, and amylase activities were 17.50% to 50.79%, 11.39% to 98.10%, 20.20% to 80.85%, 21.21% to 33.53%, and 22.17% to 34.19%, respectively, when compared to the S treatment. In summary, foliar sprays of 5-ALA, DTA-6, and additional nitrogen fertilizer enhanced rice seedling growth, increased photosynthesis, lowered Ls values, and improved seedling salt tolerance. Spraying two regulators, 5-ALA and DTA-6, quantitatively increased the effect of nitrogen fertilizer, with comparable effects on NaCl stress regulation. This study provides the basis for efficient agricultural production.
研究领域:
植物生理学
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农业科学
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胁迫生物学
·
作物科学
✓ 已验证
DOI
高影响因子
Drug Testing and Analysis
·
2026
·
IF 2.6
Tian Tian,Xi Chen,Xiaojun Deng
The gastric-emptying and satiety effects of semaglutide may lead to its misuse by athletes in weight-class sports, especially as the approved oral formulation is more convenient than subcutaneous injections. This study aimed to establish a simple ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) method for monitoring semaglutide abuse based on urinary metabolites U6 and U7, and elucidate the urinary excretion profile of the oral formulation. Multidimensional optimization determined three key factors for reliable trace detection (recovery > 90%), with enhanced hydrophobic interactions dominating the enrichment process: (i) the adsorbent, (ii) the loading pH, and (iii) the washing solvent. Orbitrap-HRMS operating in dual acquisition modes enabled both specific identification and retrospective analysis. Systematic qualitative and quantitative validation was performed, and a single oral microdose of semaglutide (3 mg) was administered to a healthy volunteer, followed by continuous urine collection for 1 week. The optimized method provided satisfactory sensitivity (limit of detection of 0.03 ng/mL) and quantitative performance (linearity range: 0.1–20 ng/mL, R 2 > 0.995; accuracy > 85%) for both U6 and U7. Excretion profiling of 25 postdose samples showed that U6 and U7 were first detectable at 21 h, peaked at 0.15 and 0.10 ng/mL, respectively, and remained detectable for up to 28 h. Additionally, five abundant metabolites of the absorption enhancer salcaprozate sodium were identified (detection window up to 7 days), serving as sensitive screening indicators for oral semaglutide. These findings demonstrate the effectiveness of the developed method and provide the first perspective on the urinary excretion profile of oral semaglutide.
✓ 已验证
DOI
高影响因子
Drug Testing and Analysis
·
2024
·
IF 2.6
Rui-Jia Chen,Zi-hua Zhang,Shenglan Yang,Shu-chen Yu,Jun-chang Wang,Ping-yong Liao,Ting-ting Qiu,Lu Xiao,Shang Xue,Hong Chen,Wen-bin Shao,Jian-wen Hu,Yun Lan,Xi-long Chen,Yue Xu,Tian-meng Zhou,Xue-jun Zhao,Wen-bin Liu
5F-MDMB-PICA, an indole-type synthetic cannabinoid (SC), was classified illicit globally in 2020. Although the extensive metabolism of 5F-MDMB-PICA in the human body warrants the development of robust analytical methods for metabolite detection and quantification, a current lack of reference standards for characteristic metabolites hinders such method creation. This work described the synthesis of 18 reference standards for 5F-MDMB-PICA and its possible Phase I metabolites, including three hydroxylated positional isomers R14 to R16 . All the compounds were systematic characterized via nuclear magnetic resonance, Fourier transform infrared spectroscopy, and high-resolution mass spectrometry. Furthermore, two methods were developed for the simultaneous detection of all standards using liquid chromatography–tandem mass spectrometry and ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry. By comparison with authentic samples, R17 was identified as a suitable urine biomarker for 5F-MDMB-PICA uptake.
研究领域:
分析化学
·
药理学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2014
·Vol. 7
·期 2
·150-157
·
IF 2.84
Xin Yao,Guisheng Zhou,Yuping Tang,Sheng Guo,Dawei Qian,Jin-ao Duan
Ginkgo biloba leaf extract has been widely used in dietary supplements and more recently in some foods and beverages. In addition to the well-known flavonol glycosides and terpene lactones, G. biloba leaves are also rich in nucleobases and nucleosides. To determine the content of nucleobases and nucleosides in G. biloba leaves at trace levels, a reliable method has been established by using hydrophilic interaction ultra performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) working in multiple reaction monitoring mode. Eleven nucleobases and nucleosides were simultaneously determined in seven min. The proposed method was fully validated in terms of linearity, sensitivity, and repeatability, as well as recovery. Furthermore, hierarchical clustering analysis (HCA) was performed to evaluate and classify the samples according to the contents of the eleven chemical constituents. The established approach could be helpful for evaluation of the potential values as dietary supplements and the quality control of G. biloba leaves, which might also be utilized for the investigation of other medicinal herbs containing nucleobases and nucleosides. Copyright © 2014 John Wiley & Sons, Ltd.
研究领域:
植物化学
·
分析化学
·
药学
✓ 已验证
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2020
·Vol. 13
·期 3
·720-728
·
IF 2.903
Cui-Mei Liu,Hong-Yuan He,Lin Xu,Zhen-Dong Hua
Performing fast qualitative identification of seized illegal drugs by Raman spectroscopy is challenging due to fluorescence interference as well as chemical complexity. Spectrometers with 785-nm excitation, 1,064-nm excitation, and sequentially shifted excitation (SSE) were compared for their effect on fluorescence reduction. The characteristic peaks method, which is independent of cutting agents, was tested as a new strategy to broaden the application of the Raman technique. The suitability of the characteristic peaks method was fully examined by analyzing a large amount of seized illegal drugs, including 72 methamphetamine hydrochloride (concentration range of 13.9%–99.4%), 68 ketamine hydrochloride (17.7%–99.8%), 176 heroin hydrochloride (5.2%–79.5%), 51 cocaine hydrochloride (21.1%–94.5%), and 33 cocaine base (30.9%–92.5%) samples. The results showed that seized methamphetamine, ketamine, and cocaine samples had no or little fluorescence. Hence, in regard to detection of these samples, the advantage of using 1,064-nm excitation and SSE compared with 785-nm excitation was quite limited. Regarding the heroin samples, a significant improvement of the “high” confident positive detected rate was evident for 1,064 nm excitation (60.8%) and SSE (61.4%), compared with 785-nm excitation (13.1%). However, it was also seen that even if 1,064-nm excitation and SSE were applied, the fluorescence of heroin samples was still unable to be fully overcome. By using the characteristic peaks method, low LOD results of 5%–20% were acquired for 40 types of drug mixtures, and lower LODs were obtained for the 60% of the drug mixtures compared with library searching method. Raman spectroscopy in conjunction with the characteristic peaks method was shown to be fast, simple, accurate, and sensitive in the qualitative analysis of seized drug samples.
研究领域:
分析化学
·
法医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2014
·Vol. 6
·期 10
·1020-1027
·
IF 2.84
Yajing Lei,Qian Zhang,Lizheng Fang,Muhammad Sajid Hamid Akash,Kanwal Rehman,Zhiming Liu,Weixing Shi,Shuqing Chen
We simultaneously set up two competitive (direct and indirect) enzyme-linked immunosorbent assays (ELISAs) based on the same antibody for estimation of cotinine (COT) in pregnant women especially and population generally exposed to environmental tobacco smoke. The results show that the limits of detection (LODs) for direct competitive ELISA and indirect competitive ELISA were 0.04 μgL -1 and 0.1 μgL -1 , respectively. Direct competitive ELISA was found to be more sensitive than indirect competitive ELISA. Thereafter, we applied our direct competitive ELISA for the detection of COT from urinary samples taken from 450 volunteers from the Zhejiang Province of China. COT was detected in 100% of participants with concentration ranging from LOD to 5358.0 μgL -1 . The GM and 95th percentile concentration of COT in pregnant women were 6.3 μgL -1 and 57.2 μgL -1 , respectively. Males had statistically higher COT concentrations than females ( P < 0.0001), active smokers had statistically higher COT concentrations than non-smokers ( P < 0.0001), whereas, non-pregnant women were found to have higher COT concentration than pregnant women. We conclude that our developed direct competitive ELISA is useful for detecting the COT in urinary concentration of human. The human urinary data obtained in this study indicated that common people generally and pregnant women especially were highly exposed to COT. Further studies are needed to focus on the sources of exposure, potential health effects and risk assessment of exposure to COT. Copyright © 2014 John Wiley & Sons, Ltd.
研究领域:
分析化学
·
环境卫生
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2019
·Vol. 11
·期 6
·898-905
·
IF 2.799
Lizhu Chen,Baohua Shen,Songtao Wang,Yingjia Yu,Hui Yan,Yan Shi,Gengli Duan,Ping Xiang
Background Chiral analysis is a crucial way to differentiate selegiline (SG) intake from drug abuse. Oral fluid (OF) has been successfully used as an alternative matrix for blood testing in several pharmacokinetic studies. Objective The aim of this study is to describe the pharmacokinetics of SG and its main metabolites in OF after a single oral administration of SG which is meaningful for results interpretation in forensic analysis. Methods Ten milligrams of SG were orally administered to 8 volunteers, and OF samples were collected for up to 96 hours by having participants spit into polypropylene tubes without stimulation. These samples were submitted to liquid–liquid extraction before analysis by liquid chromatography–tandem mass spectrometry operating in positive ion multiple-reaction monitoring mode. Results and conclusions After oral administration, each analyte could be detected in OF specimens from all volunteers with an initial detection time of 0.50 hours. The C max values of SG, R-MA, R-AM and DM-SG were 50.93–992.67 ng/mL, 29.78–653.64 ng/mL, 8.22–150.15 ng/mL, and 4.34–16.25 ng/mL, respectively, at 0.5 hours, 1–11 hours, 1.5–11 hours, and 0.5–6 hours post dose. The times when the compounds were last determined in OF were 5–24 hours for SG, 52–96 hours for R-MA, 31–96 hours for R-AM, and 13–31 hours for DM-SG after oral administration. There is a period of time in OF in which only MA and AM are present without SG and DM-SG after a single dose of SG. The pharmacokinetic data could provide supplementary interpretation for OF tests in forensic science and drug treatment programs.
研究领域:
法医学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Drug Testing and Analysis
·
2020
·Vol. 13
·期 1
·148-155
·
IF 2.903
Junping Zheng,Cheng Ye,Peng Wang,Yang Liu,Huabing Yang,Hongtao Liu
Methenolone, an anabolic androgenic steroid, has been applied to improve the quality and protein content of meat in animal husbandry. However, the usage of methenolone in sports is banned for its doping effects. Several methods have been reported to monitor the content of methenolone in serum and urine samples, but a highly sensitive detection system has not been developed for the determination of methenolone in animal source food due to its constituent complexity. In this study, a novel detection system was developed to quantify the contents of both free and conjugated methenolone in animal source food including pork, beef, mutton, milk, and eggs by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) coupled with delicate pretreatment procedures. The conjugated methenolone in the above food samples was released by dual enzyme digestion, and the total methenolone was extracted by 1% formic acid in acetonitrile, followed by the purification using a PRiME HLB column or QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) salt. The compound d 3 -methyltestosterone was used as an internal standard to minimize matrix interference. Finally, a wide linear range (0.5–20 μg/kg), low limit of detection (LOD) (0.3 μg/kg), good precision (<7% relative standard deviation), and high recovery (>90%) were obtained in the study of method validation. In summary, this analytical method provides a practicable monitoring tool for the quantification of methenolone in animal source food.
研究领域:
食品安全
·
分析化学
✓ 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）