Metabolite identification of the antimalarial piperaquine in vivo using liquid chromatography–high‐resolution mass spectrometry in combination with multiple data‐mining tools in tandem

Artemisinin‐based combination therapy is widely used for the treatment of uncomplicated Plasmodium falciparum malaria, and piperaquine (PQ) is one of important partner drugs. The pharmacokinetics of PQ is characterized by a low clearance and a large volume of distribution; however, metabolism of PQ has not been thoroughly investigated. In this work, the metabolite profiling of PQ in human and rat was studied using liquid chromatography tandem high‐resolution LTQ‐Orbitrap mass spectrometry (HRMS). The biological samples were pretreated by solid‐phase extraction. Data processes were carried out using multiple data‐mining techniques in tandem, i.e., isotope pattern filter followed by mass defect filter. A total of six metabolites (M1–M6) were identified for PQ in human (plasma and urine) and rat (plasma, urine and bile). Three reported metabolites were also found in this study, which included N‐oxidation (M1, M2) and carboxylic products (M3). The subsequent N‐oxidation of M3 resulted in a new metabolite M4 detected in urine and bile samples. A new metabolic pathway N‐dealkylation was found for PQ in human and rat, leading to two new metabolites (M5 and M6). This study demonstrated that LC‐HRMSⁿ in combination with multiple data‐mining techniques in tandem can be a valuable analytical strategy for rapid metabolite profiling of drugs. Copyright © 2016 John Wiley & Sons, Ltd.     

碳载体不同预处理方法对Pt/C电催化氧化甲醇性能的影响

本文分别用混酸水热法(HT)和混酸冷凝回流法(RF)对Vulcan XC-72R碳黑进行预处理,并进一步研究其作为Pt/C催化剂载体的性能。循环伏安实验发现,采用HT法、RF法和未预处理的碳黑作为载体的Pt/C催化剂电催化甲醇氧化的比质量活性(正扫峰电流)分别为1055、704和395 mA/mgpt,即采用HT法预处理碳载体的Pt/C催化剂具有最高的电催化活性,而且计时电流实验也表现出最好的稳定性。实验结果表明,碳载体的预处理方法对制得的Pt/C催化剂的性能具有关键性的影响,且水热法是一种效果较好的预处理碳载体的方法。     

含1,2,3-三唑环的α,γ-二酮衍生物的合成研究

以对氯氯苄为原料,经取代、1,3-偶极环加成和缩合反应得到含1,2,3-三唑环的α,γ-二酮衍生物,其结构经1H NMR、13C NMR以及MS确证。研究表明,该α,γ-二酮化合物存在酮醇异构现象,在溶液中其酮醇异构体比例近似为1∶8。     

Determination of Formaldehyde Traces in Fabric and in Indoor Air by a Kinetic Fluorimetric Method

A simple and sensitive kinetic fluorimetric method is reported for the determination of trace amount of formaldehyde. The proposed method is based on the catalytic effect of formaldehyde on the oxidation reaction of rhodamine B with potassium chlorate in sulfuric acid solution. Formaldehyde in the range of 0.020-0.340 µg/mL can be determined with a limit of detection of 5.73 ng/mL. The method has been used to determine trace formaldehyde in fabric and in indoor air. The results thus obtained show good agreement with those determined by acetyl acetone method.     

Synthesis and biological evaluation of novel 1, 2, 3-benzotriazin-4-one derivatives as leukotriene A4 hydrolase aminopeptidase inhibitors

A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A_4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC_(50) of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed.     

Improving nonlinearity tolerance of 112-Gb/s PDM OFDM systems with coherent detection using BLAST algorithm

A novel long wavelength photodetector with dual-wavelength spectral response is designed and fabricated using a step-shaped Fabry-Prot (F-P) filter structure.The step-shaped GaAs/AlGaAs distributed Bragg reflectors and the InP PIN photodetector are grown on a GaAs substrate using low pressure metal organic chemical vapor deposition.High quality GaAs/InP heteroepitaxy is realized by employing a thin low temperature buffer layer.The photodetector structure is optimized by theoretical simulation.This device has a dual-peak distance of 19 nm (1 558 and 1 577 nm).The 3-dB bandwidth of 16 GHz is simultaneously obtained with peak quantum efficiencies of 8.5% and 8.6% around 1 558 and 1 577 nm,respectively.     

Intramolecular Crosslinking of Polyvinylidene Fluoride by Homogeneous Solution Irradiation

High Energy Chemistry - Intramolecular crosslinking of polyvinylidene fluoride (PVDF) was observed to have occurred when the PVDF homogeneous solution was subject to γ-ray irradiation, which...     

石墨烯基复合材料应用于光电二氧化碳还原的基本原理，研究进展和发展前景

In response to aggravated fossil resources consuming and greenhouse effect, CO₂ reduction has become a globally important scientific issue because this method can be used to produce value-added feedstock for application in alternative energy supply. Photoelectrocatalysis, achieved by combining optical energy and external electrical bias, is a feasible and promising system for CO₂ reduction. In particular, applying graphene in tuning photoelectrochemical CO₂ reduction has aroused considerable attention because graphene is advantageous for enhancing CO₂ adsorption, facilitating electrons transfer, and thus optimizing the performance of graphene-based composite electrodes. In this review, we elaborate the fundamental principle, basic preparation methods, and recent progress in developing a variety of graphene-based composite electrodes for photoelectrochemical reduction of CO₂ into solar fuels and chemicals. We also present a perspective on the opportunities and challenges for future research in this booming area and highlight the potential evolution strategies for advancing the research on photoelectrochemical CO₂ reduction.