Preparation and properties of polyaniline codoped with ionic liquid and dodecyl benzene sulfonic acid or hydrochloric acid

Three nanosized polyaniline (PAn) powders doped with ionic liquid and dodecyl benzene sulfonic acid (DBSA) or hydrochloric acid have been prepared for the first time in an ionic liquid-water emulsion system. The oil-phase ionic liquid is used as both a monomer solvent and doped counterion. The effects of different counterions on the properties (molecular weight, electrical conductivity, glass transition temperature, electrochemical activity) of PAn are investigated. PAn codoped with 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid and DBSA shows the highest molecular weight (81 104 g mol^?1), the highest electrical conductivity (1.85 S cm^?1), the lowest glass transition temperature (181°C) and the highest redox reaction current density; PAn doped with an ionic liquid only exhibits the lowest conductivity (0.0018 S cm^?1) and a lower redox reaction current density. PAn codoped with ionic liquid and HCl shows higher conductivity. They also exhibit good electrochemical stability and charge-discharge performance. These indicate that codoping of different counterions under acidic conditions could improve the degree of oxidation and doping ratio of PAn and could result in high electrical conductivity and good electrochemical properties.     

LC Determination of Helicidum in Beagle Dog Plasma: Study on the Pharmacokinetics of Helicidum Orally Disintegrating Tablets Compared to Conventional Tablets

A sensitive and reproducible liquid chromatographic method with UV detection was described for the determination of helicidum in beagle dog plasma. Sample preparation was accomplished through protein precipitation with 15% perchloric acid and chromatographic separation was performed on a reversed phase C₁₈ column at 30 °C. Mobile phase consisted of a mixture of acetonitrile–water at a flow rate of 1.0 mL min^?1. Wavelength was set at 270 nm. The method was applied to a pharmacokinetic study of two formulations of helicidum. No statistical difference in the t _1/2 (AUC_0–5, AUC_0–∞) between the two formulations were observed. The t _max of helicidum ODTs is significantly shorter than that of conventional tablets (0.84 h vs. 1.33 h, P< 0.05).     

Phenoxazine-based supramolecular tetrahedron as biomimetic lectin for glucosamine recognition

The design and synthesis of a phenoxazine-based metal-organic tetrahedro n(Zn_4L_4) as biomimetic lectin for selectively recognition of glucosamine(GlcN) was reported.Different from the free phenoxazinebased ligand(L),Zn_4L_4 displayed the highest fluorescent intensity enhancement efficiency toward GlcN over other related natural mono-and disaccharides.Fluorescence titration demonstrated a 1:1 stoichiometric host-guest complex was formed with an association constant about 4.03 × 10~4 L/mol.~1H NMR spectroscopic studies confirmed this selectivity resulted from the multiple hydrogen bonding interactions formed between GlcN and Zn_4L_4.The present results suggested that rational arrangement of recognition sites in the confined space of metal-organic cage is crucial for the selectivity toward target guests.     

金属有机框架(MOFs)材料在锂离子电池及锂金属电池电解液中的应用

总结了金属有机框架(MOFs)材料在锂离子电池电解液中的研究进展.通过归纳锂离子电池长期存在的一些缺陷,随后将MOFs材料作为离子筛、人造负极保护层、准固态电解质以及用来调节电解液构型,使得锂离子电池的性能得到显著提升.最后,基于MOFs材料本身的特性,还对MOFs材料在电化学储能领域中的后续应用进行了合理地前瞻性展望...     

Jatrolignans C and D: New Neolignan Epimers from Jatropha curcas

Two new neolignans jatrolignans, C (1) and D (2), a pair of epimers, were isolated from the whole plants of Jatropha curcas L. (Euphorbiaceae). Their structures were determined with HRESIMS, IR, and NMR data analysis, and electronic circular dichroism (ECD) experiments via a comparison of the experimental and the calculated ECD spectra. Their antichlamydial activity was evaluated in Chlamydia abortus. They both showed dose-dependent antichlamydial effects. Significant growth inhibitory effects were observed at a minimum concentration of 40 μM.     

A Comprehensive Review on the Benefits and Problems of Curcumin with Respect to Human Health

Curcumin is the most important active component in turmeric extracts. Curcumin, a natural monomer from plants has received a considerable attention as a dietary supplement, exhibiting evident activity in a wide range of human pathological conditions. In general, curcumin is beneficial to human health, demonstrating pharmacological activities of anti-inflammation and antioxidation, as well as antitumor and immune regulation activities. Curcumin also presents therapeutic potential in neurodegenerative, cardiovascular and cerebrovascular diseases. In this review article, we summarize the advancements made in recent years with respect to curcumin as a biologically active agent in malignant tumors, Alzheimer’s disease (AD), hematological diseases and viral infectious diseases. We also focus on problems associated with curcumin from basic research to clinical translation, such as its low solubility, leading to poor bioavailability, as well as the controversy surrounding the association between curcumin purity and effect. Through a review and summary of the clinical research on curcumin and case reports of adverse effects, we found that the clinical transformation of curcumin is not successful, and excessive intake of curcumin may have adverse effects on the kidneys, heart, liver, blood and immune system, which leads us to warn that curcumin has a long way to go from basic research to application transformation.     

Simultaneous Determination of Seven Pesticides and Metabolite Residues in Litchi and Longan through High-Performance Liquid Chromatography-Tandem Mass Spectrometry with Modified QuEChERS

This study established a QuEChERS high-performance liquid chromatography/tandem triple-quadrupole mass spectrometry method for determining azoxystrobin, pyraclostrobin, picoxystrobin, difenoconazole, chlorantraniliprole, imidacloprid, and cyantraniliprole and its metabolite (IN-J9Z38) in litchi and longan, and applied this method to the real samples. The residues in samples were extracted with acetonitrile and purified with nano-ZrO₂, C₁₈, and PSA. The samples were then detected with multireactive ion monitoring and electrospray ionization in the positive ion mode and quantified using the external matrix-matched standard method. The results showed good linearities for the eight analytes in the range of 1–100 μg/L, with correlation coefficients (r²) of >0.99. The limit of quantification was 1–10 μg/kg, and the limit of detection was 0.3–3 μg/kg. Average recovery from litchi and longan was 81–99%, with the relative standard deviation of 3.5–8.4% at fortified concentrations of 1, 10, and 100 μg/kg. The developed method is simple, rapid, efficient, and sensitive. It allowed the rapid screening, monitoring, and confirming of the aforementioned seven pesticides and a metabolite in litchi and longan.     

离子选择电极—流动注射分析法动力学测定葡萄糖存在下的果糖

本文将离子电极与流动注射分析相结合，利用３０℃下，在强碱性介质中，果糖和葡萄糖与２，４－二硝基酚钠反应速度明显差异，动力学测定了葡萄糖存在下果糖的含量。自制了２，４－二硝基酚电极作为动力学电位测定用的工作电极。本法测定果糖的范围为０．０２～１．００ｍｏｌ／Ｌ，其ＲＳＤ为４．０％～４．９％，ＲＥ为１．０～５．０％；当Ｃ葡／Ｃ果≤３倍时，葡萄糖的干扰不超过５％；本法也曾成功地用于果葡萄浆测定，其ＲＳＤ     

Enrichment and separation of rebaudioside A from stevia glycosides by a novel adsorbent with pyridyl group

The adsorptive capacity and selectivity of a novel adsorbent with pyridyl group toward stevia glycosides were studied. The effect of polarity and physical structure of the sorbent on the selectivity was investigated in detail. Two separation methods were applied in the enrichment of rebaudioside A(RA). They were selective elution using methanol or ethanol solution as solvent, and dynamic chromatographic separation using pyridyl resin with high selectivity. Results show that the chromatographic separation method can effectively enrich RA from stevia glycoside with high content of stevioside.     

Preparative isolation and purification of atractylon and atractylenolide III from the Chinese medicinal plant atractylodes macrocephala by high-speed counter-current chromatography

The medicinal plant Atractylodes macrocephala (Baizhu in Chinese) has been widely used in traditional Chinese medicine for energy and stomach complaints, treatment of dyspepsia and anorexia, anti-inflammation, anticancer and for increasing assimilation. A high-speed counter-current chromatography (HSCCC) method was developed for the preparative separation and purification of two main bioactive components, namely, atractylon and atractylenolide III from A. macrocephala by using light petroleum (60-90 degrees C)-ethyl acetate-ethanol-water (4:1:4:1 v/v) as the two-phase solvent system in dual-mode elution. Compared with the separation using the normal-mode elution, the dual-mode HSCCC can be achieved with shorter elution time. Atractylenolide III (32.1 mg) at 99.0% purity and 319.6 mg atractylon at 97.8% purity could be obtained from 1000 mg crude sample in a single run. The recoveries of atractylenolide III and atractylon were 95.4 and 92.6%, respectively.