Heliyon
·
2024
·
IF 3.4
Shunqin Chen,Han Yang,Shan Zhang,Faze Zhu,Shan Liu,Huan Gao,Qing Diao,Wenbo Ding,Yuemeng Chen,Peng Luo,Yubo Liu
This study developed an online solid-phase extraction ultra-high performance liquid chromatography-tandem mass spectrometry (Online-SPE-UHPLC-MS/MS) method for the analysis of 28 illegal drugs in sewage. To achieve this, 28 isotope internal standards (ISTDs) were added to 3 mL sewage samples, the pH was adjusted to 7–8 using hydrochloric acid or 20% ammonia water, followed by centrifugation, filtration, and analysis using UHPLC-MS/MS. The results indicated an excellent linearity of 1–300 ng L −1 , and cotinine in the concentration range of 20–6000 ng L −1 , linear correlation coefficient R 2 > 0.995, with the limit of detection (LOD) of 0.01–6 ng L −1 , and a limit of quantification (LOQ) of 0.1–20 ng L −1 . The addition of three concentrates of low (2 ng L −1 /40 ng L −1 ), medium (20 ng L −1 /400 ng L −1 ), and high concentration (200 ng L −1 /4000 ng L −1 ) demonstrated the matrix effect of the target compound between ± 22.0%. The extraction recovery was 70.0–119.4%, and a percent accuracy of 75.7–118.1%. Similarly, the intra- and inter-day precisions were 1.8–20.0% and 1.5–18.9%, respectively. The results cemented the sensitivity, accuracy, reliability, strong specificity, and reproducibility, which can be used to screen 28 illegal drugs in sewage for trace analysis.
研究领域:
环境科学
·
分析化学
·
毒理学
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产品关联
DOI
PubMed
高影响因子
PHYTOCHEMISTRY
·
2025
·
IF 3.4
Junguo Huang,Shan Ran,Guanghui Yang,Liangxiu Liao,Di Li,Qingpei Liu,Wenjing Wang,Xiaolong Yang
Five previously undescribed compounds, including one di- nor -lanostanoid aspverslanostane A ( 1 ), one indole diketopiperazine (indole DKP) alkaloid aspversamide A ( 2 ), and three itaconic acid derivatives asperitaconic acids D–F ( 13 – 15 ), along with 15 previously identified compounds, are isolated from the endophytic fungus Aspergillus versicolor HYQZ-324. The structures of compounds are elucidated via comprehensive spectroscopic analyses and electronic circular-dichroism calculations. Aspverslanostane A ( 1 ) represents the first example of a naturally occurring triterpene both with the 28- and 29-methyl groups demethylated. Aspversamide A ( 2 ) exhibits a distinctive skeletal structure of indole DKPs, characterised by an additional benzofuranone moiety at C-8. The compounds selected are subjected to anti-bacterial activity assays against eight clinically resistant bacteria, and none of the compounds exhibit satisfactory activity.
研究领域:
天然产物化学
·
微生物学
·
药理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF APPLIED TOXICOLOGY
·
2026
·
IF 3.1
Xue-Min Shan,Zhao-Hang Wang,Yi Zhou,Li-Jiang Peng,Xing-Wei Yang
In recent years, olaflur, mainly containing three amine hydrofluorides (compounds 1–3 ), has been widely used as a cariostatic agent in children's toothpaste. However, there is no report on the systematic toxic evaluation of olaflur thus far. Therefore, acute and 28-day repeated dose oral toxicity studies of commercial olaflur and 1–3 were conducted in rats. Two inorganic fluorides, sodium fluoride (NaF) and sodium monofluorophosphate (SMFP), were selected as positive controls in the 28-day study. The acute oral LD 50 values were determined as 35.0, 28.3, 36.5, and 30.7 mg F/kg for commercial olaflur and 1–3 , respectively, indicating higher toxicity than inorganic fluorides. In the 28-day study, olaflur and 1–3 primarily induced hepatic, splenic, pulmonary, and gastrointestinal toxicity. In particular, at doses of 4 and 10 mg F/kg, the spleen exhibited punctate necrosis and the duodenum and jejunum exhibited edema of the intestinal villi, whereas these toxic effects were not observed in all NaF/SMFP groups. Structural-toxicity analysis of these amine hydrofluorides and inorganic fluorides reveals that the protonated alkylamine moiety contributes significant additional gastrointestinal toxicity beyond the fluoride ion. These findings strongly urge caution in the use of olaflur and its constituents as dentifrice additives, particularly for children's toothpaste.
✓ 已验证
DOI
PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2024
·Vol. 108
·期 1
·1-13
·
IF 3.9
Wu Zongzhan,Dou Wenyu,Yang Xiaolin,Niu Tengfei,Han Zhuzhen,Yang Li,Wang Rufeng,Wang Zhengtao
Abstract Oleanane-type ginsenosides are a class of compounds with remarkable pharmacological activities. However, the lack of effective preparation methods for specific rare ginsenosides has hindered the exploration of their pharmacological properties. In this study, a novel glycoside hydrolase Pl GH3 was cloned from Paenibacillus lactis 154 and heterologous expressed in Escherichia coli . Sequence analysis revealed that Pl GH3 consists of 749 amino acids with a molecular weight of 89.5 kDa, exhibiting the characteristic features of the glycoside hydrolase 3 family. The enzymatic characterization results of Pl GH3 showed that the optimal reaction pH and temperature was 8 and 50 °C by using p -nitrophenyl- β - d -glucopyranoside as a substrate, respectively. The K m and k cat values towards ginsenoside Ro were 79.59 ± 3.42 µM and 18.52 s −1 , respectively. Pl GH3 exhibits a highly specific activity on hydrolyzing the 28- O - β - d -glucopyranosyl ester bond of oleanane-type saponins. The mechanism of hydrolysis specificity was then presumably elucidated through molecular docking. Eventually, four kinds of rare oleanane-type ginsenosides (calenduloside E, pseudoginsenoside RP1, zingibroside R1, and tarasaponin VI) were successfully prepared by biotransforming total saponins extracted from Panax japonicus . This study contributes to understanding the mechanism of enzymatic hydrolysis of the GH3 family and provides a practical route for the preparation of rare oleanane-type ginsenosides through biotransformation. Key points • The glucose at C-28 in oleanane-type saponins can be directionally hydrolyzed. • Mechanisms to interpret PlGH3 substrate specificity by molecular docking. • Case of preparation of low-sugar alternative saponins by directed hydrolysis.
研究领域:
生物化学
·
药理学
·
微生物学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2019
·
IF 6.35
Jingyun Huang,Bo Yang,Jinian Shu,Zuojian Zhang,Zhen Li,Kui Jiang
Excited-state CH2Cl2-induced associative ionization (AI) is a newly developed ionization method that is very effective for oxygenated organics. However, this method is not widely known. In this study, an unprecedented ionization efficiency and ultrafast reaction rate of AI toward nitro compounds were observed. The ionization efficiencies of o-nitrotoluene (o-NT), m-nitrotoluene (m-NT), and nitrobenzene (NB) were as high as (28 ± 3)%, (27 ± 2)%, and (13 ± 1)%, respectively (∼1–3 ions for every 10 molecules). The measured reaction rate coefficients of these nitroaromatics were (0.5–1.3) × 10–7 molecule–1 cm3 s–1 (∼300 K). These unusual rate coefficients indicated strong long-range interactions between the two neutral reactants, which was regarded as a key factor leading to the ultrahigh ionization efficiency. The detection sensitivities of the nitroaromatics, (1.01–2.16) × 104 counts pptv–1 in 10 s acquisition time, were obtained by an AI time-of-flight mass spectrometer (AI-TOFMS). These experimental results not only provide new insight into the AI reaction but also reveal an excellent ionization method that can improve the detection sensitivity of nitroaromatics to an unprecedented degree.
研究领域:
化学
·
分析化学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
·
2015
·Vol. 28
·期 2
·230-234
·
IF 0.498
Jiang Zhen-ya,Yan Li-feng
Biomass-derived hexose sugars, the most abundant renewable resources in the world, have potential to be the sustainable resources for production of platform chemicals. Here, conversion of glucose is investigated by using sulfonated graphene (rGO-SO 3 H) as solid acid catalyst in water without any organic solvent. At first, graphene functionalized with sulfonic acid groups is prepared by using NaH and propane sultone, and then it is characterized by means of XPS, FT-IR, and TEM to confirm the existence of the sulfonic acid groups. The catalytic activity of rGO-SO 3 H in the conversion of glucose to valuable chemicals is studied under different reaction conditions. The maximum yield of 5-hydroxymethylfurfural (HMF) is 28.8%, and the total yield of formic acid, lactic acid and HMF is 51.94% when the reaction is conducted at the optimized reaction condition. In addition, the rGO-SO 3 H gives a relatively high total yield of the three kinds of products after five run experiments, indicating that the catalyst shows good thermal stability.
研究领域:
化学工程
·
可再生资源利用
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Jia Jia Hu,Jian Ping Wang
In this study, two magnetic activity-based protein profiling probes based on cephradine and amoxicillin were first synthesized that were used to produce the natural penicillin-binding protein 2 of Escherichia coli. After characterization by using LC-ESI-MS/MS, it was found that the obtained proteins by using the two probes were the same. The molecular docking for 28 beta-lactam antibiotics showed that the key amino acids were Ser330 and Ser387, the main intermolecular forces were hydrogen bond and hydrophobic interaction, and the main binding sites in their molecules were on the beta-lactam ring. Then this protein was combined with streptavidin-labeled tracer and biotinylated fluorescein isothiocyanate to establish a signal-amplified fluorescence polarization assay to determine the 28 drugs in milk. The limits of detection ranged from 0.07 to 2.21 ng/mL, and the sensitivities for the 28 drugs were improved 4 to 48-fold in comparison with the use of a fluorescein isothiocyanate-labeled fluorescent tracer. Therefore, this method could be used for rapid multiscreening of the 28 beta-lactam antibiotics in milk.
研究领域:
分析化学
·
药学
·
生物化学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Chinese Physics B
·
2019
·Vol. 28
·期 8
·086601
·
IF 1.469
Xing-Yu Zhao,Li-Na Wang,Hong-Mei Yin,Heng-Wei Zhou,Yi-Neng Huang
A measurement scheme for detecting the α relaxation time (τ) of glass-forming liquid is proposed, which is based on the measured ionic conductivity of the liquid doped with probing ions by low- and middle-frequency dielectric spectroscopy and according to the Nernst–Einstein, Stokes–Einstein, and Maxwell equations. The obtained τ values of glycerol and propylene carbonate by the scheme are consistent with those obtained by traditional dielectric spectroscopy, which confirms its reliability and accuracy. Moreover, the τ of 1,2-propanediol in a larger temperature range is compared with existing data.
研究领域:
物理化学
·
材料科学
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DOI
高影响因子
NANOTECHNOLOGY
·
2016
·Vol. 28
·期 3
·035601
·
IF 3.573
Jin Shen,Chunlei Wang,Shuhong Xu,Changgui Lv,Ruohu Zhang,Yiping Cui
In this work, highly luminescent quaternary CuNiInS nanocrystals (NCs) are put forward as a good prototype for investigating defect-induced room temperature ferromagnetism. A ferromagnetic Ni cation can preserve the strong luminescence of NCs without introducing intermediate energy levels in the center of the forbidden band. The strong luminescence of NCs is used as an indicator for monitoring the concentration of vacancy defects inside them, facilitating the investigation of the origin of room temperature ferromagnetism in CuNiInS NCs. Our results reveal that the patching of Cu vacancies ({{{\rm{V}}}_{{\rm{Cu}}}}^{-}) with Ni will result in bound magnetic polarons composed of both {{{\rm{V}}}_{{\rm{Cu}}}}^{-} and a substitution of Cu by Ni ({{{\rm{Ni}}}_{{\rm{Cu}}}}^{+}), giving rise to the room temperature ferromagnetism of CuNiInS NCs. Either the ferromagnetic Ni or the non-ferromagnetic Cu cation can tune the magnetism of CuNiInS NCs because of the change of bound magnetic polaron concentration at the altered concentration ratio of {{{\rm{V}}}_{{\rm{Cu}}}}^{-} and {{{\rm{Ni}}}_{{\rm{Cu}}}}^{+}.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
PubMed
高影响因子
Chinese Physics B
·
2019
·Vol. 28
·期 3
·037803
·
IF 1.469
Xinli Ma,Rongjie Zhang,Chunhua An,Sen Wu,Xiaodong Hu,Jing Liu
Transition metal dichalcogenides (TMDCs) belong to a subgroup of two-dimensional (2D) materials which usually possess thickness-dependent band structures and semiconducting properties. Therefore, for TMDCs to be widely used in electronic and optoelectronic applications, two critical issues need to be addressed, which are thickness-controllable fabrication and doping modulation of TMDCs. In this work, we successfully obtained monolayer WS2 and achieved its efficient doping by chemical vapor deposition and chemical doping, respectively. The n- and p-type dopings of the monolayer WS2 were achieved by drop coating electron donor and acceptor solutions of triphenylphosphine (PPh3) and gold chloride (AuCl3), respectively, on the surface, which donates and captures electrons to/from the WS2 surface through charge transfer, respectively. Both doping effects were investigated in terms of the electrical properties of the fabricated field effect transistors. After chemical doping, the calculated mobility and density of electrons/holes are around 74.6/39.5 cm2·V−1·s−1 and 1.0 × 1012/4.2 × 1011 cm−2, respectively. Moreover, we fabricated a lateral WS2 p–n homojunction consisting of non-doped n-type and p-doped p-type regions, which showed great potential for photodetection with a response time of 1.5 s and responsivity of 5.8 A/W at VG = 0 V and VD = 1 V under 532 nm light illumination.
研究领域:
材料科学
·
电子工程
·
光学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2014
·Vol. 25
·期 28
·285501
·
IF 3.672
Wenyan Liu,Yu Zhang,Hua Wu,Yi Feng,Tieqiang Zhang,Wenzhu Gao,Hairong Chu,Jingzhi Yin,Tian Cui,Yiding Wang,Jun Zhao,William W. Yu
This work describes a micrometer resolution and plane-array temperature-sensing method using the photoluminescence (PL) of ZnCuInS/ZnSe/ZnS quantum dots (QDs). Heavy-metal-free QDs were directly deposited on a printed circuit board to analyze the surface temperature of the devices on the board. An optical fiber monochromator and a high-powered microscope were employed to fabricate a system which could collect temperature-dependent QD emissions from the micrometer area for the temperature measurements. This system realizes the imaging of the surface temperature distribution in the planar micrometer area. Temperature sensitivity of the PL intensity reached 0.66% °C−1, and the relative error was less than 2%.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2016
·Vol. 28
·期 2
·025604
·
IF 3.573
Xiaowen Zhang,Yang Li,Chenxing Liao,Zhi Chen,Jianrong Qiu
Fluorescence imaging in the second near-infrared window (NIR-II, 1000–1400 nm) is attracting extensive attention. Mn6+ doped BaSO4 with broadband emission from 900 nm to 1400 nm is emerging as a new class of NIR phosphor for fluorescence imaging. Manganese has diverse valence states, thus it is difficult to prevent valence change of Mn6+ during traditional synthesis process. In this work, BaSO4:Mn6+ nanoparticles with uniform size and morphology were first successfully prepared through a fast liquid-solid solution route at room temperature. The nanoparticles exhibit broadband NIR emission from Mn6+ when excited by 808 nm lasers. This convenient strategy, based on an efficient anion exchange reaction, is proved effective for synthesizing nano-sized materials. The results reveal that our strategy has great potential in fabricating special valence state ion doped nanomaterials.
研究领域:
材料科学
·
生物医学工程
·
光学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）