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Jiaqi He Yu Yin Yingjie Shao Wenkai Zhang Yanling Lin Xiuping Qian Qizhi Ren 《Molecules (Basel, Switzerland)》2022,27(18)
Porphyrin derivatives are popular photodynamic therapy (PDT) agents; however, their typical insolubility in water has made it challenging to separate cells of organisms in a liquid water environment. Herein, a novel water-soluble 5,10,15,20-tetrakis(4-methoxyphenyl-3-sulfonatophenyl) porphyrin (TMPPS) was synthesized with 95% yield by modifying the traditional sulfonation route. The reaction of TMPPS with AgNO3 afforded AgTMPPS an unusual Ag(II) oxidation state (97% yield). The free base and Ag(II) complex were characterized by matrix-assisted laser desorption ionization-mass spectroscopy, and 1H nuclear magnetic resonance, Fourier-transform infrared, UV-vis, fluorescence, and X-ray photolectron spectroscopies. Upon 460 nm laser irradiation, AgTMPPS generated a large amount of 1O2, whereas no ⦁OH was detected. Antibacterial experiments on methicillin-resistant Staphylococcus aureus (MRSA) revealed that the combined action of AgⅡ ions and PDT could endow AgTMPPS with a 100% bactericidal ratio for highly concentrated MRSA (108 CFU/mL) at a very low dosage (4 μM) under laser irradiation at 360 J/cm2. Another PDT response was demonstrated by photocatalytically oxidizing 1,4-dihydronicotinamide adenine dinucleotide to NAD+ with AgTMPPS. The structural features of the TMPPS and AgTMPPS molecules were investigated by density functional theory quantum chemical calculations to demonstrate the efficient chemical and photodynamical effects of AgTMPPS for non-invasive antibacterial therapy. 相似文献
3.
Auricularia polytricha is an edible mushroom, quite popular in China. Modern pharmacology research indicate that A. polytricha polysaccharides possess antitumor and immunomodulatory activities. In this paper, an antitumor Auricularia polytricha polysaccharide (APS)-2 was purified by radial flow chromatography (RFC) in a column of 500 mL bed-volume (40 cm i.d × 15 cm) packed with DEAE52-cellulose anion ion-exchange resin. The optimal separation conditions were: sample flow-velocity 15–20 mL min?1, sample volume 160–200 mL, and elution with distilled water and 0.2 M NaCl at a velocity of 35–45 mL min?1. The yield and content of APS-2 obtained under these conditions were 182 mg g?1 total polysaccharides and 98.35 %, respectively. The study provides guidelines for the separation and purification of polysaccharides using a radial flow chromatography column. 相似文献
4.
制备了金属-有机骨架(MOF)MIL-101(Cr)掺杂聚合物整体柱,建立了在线固相萃取-高效液相色谱检测水中4-硝基苯酚、2-硝基苯酚、3-甲基苯酚和2,4-二氯苯酚的方法。考察了样品溶液pH值、上样时间、上样流速和解吸时间对酚类化合物萃取效果的影响。在最优萃取条件下,采用制备的整体柱检测水中酚类化合物,其富集因子高,线性范围宽,精密度好,检出限低,适用于水中酚类化合物的检测。制备掺杂聚合物整体柱是促进和拓宽MOFs在线固相萃取应用的有效方法之一。 相似文献
5.
Qian Wang Dr. Shayu Li Dr. Liming He Dr. Yan Qian Dr. Xiuping Li Dr. Wenhao Sun Dr. Min Liu Dr. Juan Li Dr. Yi Li Prof. Guoqiang Yang Prof. 《Chemphyschem》2008,9(8):1146-1152
A series of dicyanovinyl‐substituted aromatic compounds (Ar‐DCV; Ar=9‐anthracenyl, 1‐naphthyl, 1‐pyrenyl) with dual fluorescence are prepared, and their emission properties—when molecularly dispersed in a polymer medium—are investigated under pressure perturbation. The total emission intensity is enhanced drastically from ambient pressure up to 70 kbar. Emission 30–107 times more intense than that at ambient pressure is observed at higher pressure. In dual emission, the enhancement of the local excited state (LE state) is significantly different from that of the intramolecular charge‐transfer state (ICT state). The intensity of the ICT emission increases faster (30–370 times) than that of the LE emission (less than 20 times). In accordance with spectroscopic data, emission dynamics at different pressures, and computational studies on the molecular conformations of these compounds, a kinetic model is proposed to explain the effect of pressure on the emissive properties of the Ar‐DCV compounds from the point of view of pressure‐dependent populations of the species in the ground state. 相似文献
6.
Proteolysis is a central component of most proteomics methods. Unfortunately much of the information relating to the structural diversity of proteins is lost during digestion. This paper describes a method in which the native proteome of yeast was subjected to preliminary fractionation by size exclusion chromatography (SEC) prior to trypsin digestion of SEC fractions and reversed phase chromatography-mass spectral analysis to identify tryptic peptides thus generated. Through this approach proteins associated with other proteins in high molecular mass complexes were recognized and identified. A focus of this work was on the identification of Hub proteins that associate with multiple interaction partners. A critical component of this strategy is to choose methods and conditions that maximize retention of native structure during the various stages of analysis prior to proteolysis, especially during cell lysis. Maximum survival of protein complexes during lysis was obtained with the French press and bead-beater methods of cell disruption at approximately pH 8 with 200 mM NaCl in the lysis buffer. Structure retention was favored by higher ionic strength, suggesting that hydrophobic effects are important in maintaining the structure of protein complexes. Recovery of protein complexes declined substantially with storage at any temperature, but storage at -20°C was best when low temperature storage was necessary. Slightly lower recovery was obtained with storage at -80°C while lowest recovery was achieved at 4°C. It was concluded that initial fractionation of native proteins in cell lysates by SEC prior to RPC-MS/MS of tryptic digests can be used to recognize and identify proteins in complexes along with their interaction partners in known protein complexes. 相似文献
7.
Tetramic acid derivatives and polyphenols from sponge-derived fungus and their biological evaluation
Jun-Feng Wang Xiaochu Qin Fu-Quan Xu Tianyu Zhang Shengrong Liao Xiuping Lin 《Natural product research》2015,29(18):1761-1765
Fifteen compounds, including two tetramic acid derivatives, penicillenol A1 (1) and penicillenol A2 (2), six polyphenols containing both phenolic bisabolane sesquiterpenoid and diphenyl ether units, expansols A–F (3–8), together with six phenolic bisabolane sesquiterpenoids (9–14) and diorcinol (15), were isolated from the fermentation broth of the marine-derived fungus ZSDS1-F11 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by using extensive NMR spectroscopic and mass spectrometric analyses. Compounds 3–5, 7 and 8 showed potent COX-1 inhibitory activity with IC50 values of 5.3, 16.2, 30.2, 41.0 and 56.8 μM, respectively. Meanwhile, compounds 3–8 showed potent COX-2 inhibitory activity with IC50 values of 3.1, 5.6, 3.0, 5.1, 3.2 and 3.7 μM, respectively. In addition, compound 1 exhibited antituberculosis activity with 96.1% inhibition at concentration of 10 μM. 相似文献
8.
保留指数是气相色谱中用于化合物结构鉴定的重要工具。本研究对基于正构烷烃和直链脂肪酸甲酯的线性保留指数进行线性拟合,发现在所设定的4种不同的升温条件下两种保留指数之间呈现较为固定的线性关系:在弱极性柱(固定液为5%苯基和95%的甲基聚硅氧烷)和极性柱(固定液为聚乙二醇)条件下,正构烷烃保留指数(y)与脂肪酸甲酯保留指数(x)之间的关系分别为y=1.005 1x+318.51(r2=1)和y=1.036 2x+562.519(r2=1)。采用文献保留指数对所建立的线性关系进行验证,发现通过公式换算得到的保留指数均在其对应文献值的均值加减方差范围内,说明换算公式真实有效。两种保留指数之间关系的建立对于化合物结构鉴定时扩大保留指数搜索范围、减少保留指数测定实验具有重要意义。 相似文献
9.
采用短碳链的表面活性剂溴代十二烷基三甲基溴化铵为模板剂,合成了具有较大粒径和超小孔径分布的单分散树枝状介孔二氧化硅纳米球(记为DMSNs-C12).通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射能谱(XRD)、傅里叶变换红外光谱(FT-IR)、以及氮气吸附脱附曲线对制备的DMSNs-C12进行了形貌、晶体结构、化学组成、孔体积、比表面积等分析.结果表明:与传统的、以溴代十六烷基三甲基溴化铵为模板剂制备的单分散树枝状二氧化硅纳米球相比(DMSNs-C16),DMSNs-C12颗粒尺寸明显增大,褶皱结构消失,孔道尺寸急剧减小.原因是随着碳链减小,表面活性剂相互斥力减弱,影响微乳液形成,最终导致结构差异. 相似文献
10.
电热原子吸收光谱法中原子形成机理的热力学和动力学研究 总被引:2,自引:1,他引:1
本文对电热原子吸收光谱法(ETAAS)中气态原子形成机理的热力学和动力学研究状况进行了评述,引用文献62篇。 相似文献