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101.
102.
《Ceramics International》2015,41(6):7565-7572
A variety of advanced functions such as hydrophilicity and hydrophobicity are required for transparent glass plates recently. This paper reports a new procedure to produce transparent silica thin films on glass plates obtained from sodium silicate as inexpensive silica source by its dip coating and subsequent deposition of silica with (NH4)2SO4 solution. When the thin films were prepared using bovine serum albumin (BSA), the resulting transparent films became more hydrophobic than that obtained without BSA and had good adhesion with water droplet, the so-called “petal effect”. Water droplet on the silica thin film did not slide down even when the substrate turned vertically and upside down. Although no BSA was included in the silica thin film, BSA contributed to the formation of nano-sized asperity structures in the film, producing more hydrophobic (less hydrophilic) property and the petal effect. 相似文献
103.
以咖啡酸、间羟基肉桂酸为母体,分别与止血芳酸反应,设计合成两种羟基肉桂酸衍生物I、II,并用MS、IR、1H-NMR、13C-NMR进行结构表征。采用荧光光谱法、同步荧光光谱法、紫外可见光谱法结合分子对接技术研究其在体外生理条件下与HSA之间的相互作用机制。光谱实验结果表明,衍生物I和II都可以使HSA的内源荧光发生静态猝灭,相互作用力主要是氢键和范德华力,且对HSA的构象产生一定的影响。分子对接结果表明衍生物I、II与HSA中的结合位于亚结构域IIA(即site I)中,作用力主要是氢键和范德华力,同时还存在着疏水作用,且衍生物距色氨酸残基(Trp214)很近,很好地解释了衍生物有效猝灭HSA内源荧光的实验现象。分子对接与实验获得了一致性的结果,二者相互作证,提高了实验结果推断的准确度。 相似文献
104.
利用了荧光发射光谱,同步荧光光谱,紫外吸收光谱进行了检测,研究有机磷农药(草甘膦和马拉硫磷)与牛血清白蛋白的相互作用,实验结果表明了有机磷农药对牛血清白蛋白有着明显的荧光猝灭作用,且方式为静态猝灭(BSA荧光分子与猝灭剂有机磷农药之间通过弱的结合生成复合物,该复合物会使得荧光完全猝灭的现象)为主。通过实验得出有机磷与牛血清白蛋白的结合位点数(n),与结合常数(K0)。 相似文献
105.
106.
Tanaka T Tanaka M Tanaka T Ishigamori R 《International journal of molecular sciences》2010,11(9):3209-3225
Colorectal cancer (CRC) is the third most common epithelial malignancy in the world. Since CRC develops slowly from removable precancerous lesions, detection of the lesion at an early stage by regular health examinations can reduce the incidence and mortality of this malignancy. Colonoscopy significantly improves the detection rate of CRC, but the examination is expensive and inconvenient. Therefore, we need novel biomarkers that are non-invasive to enable us to detect CRC quite early. A number of validation studies have been conducted to evaluate genetic, epigenetic or protein markers for identification in the stool and/or serum. Currently, the fecal occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics will lead to the discovery of novel non-invasive biomarkers. 相似文献
107.
108.
利用紫外-可见吸收光谱和荧光光谱法研究棉酚及其氧化物与牛血清蛋白(bovine serum albumin,BSA)的结合作用。实验结果表明,棉酚及其氧化物与牛血清蛋白相互作用而引起的荧光猝灭机制均属于动态和静态的联合猝灭,BSA发射峰蓝移。通过计算各个结合参数得出:棉酚及其氧化物与BSA的结合常数在105数量级,说明棉酚及其氧化物与BSA有很强的结合,结合位点均为1;热力学参数ΔH0、ΔS0和ΔG0,表明棉酚及其氧化物与BSA结合的主要作用力为疏水作用力和氢键。根据Forster的非辐射能量转移理论,计算供体(BSA)与受体(棉酚及其氧化物)间的结合距离r分别为2.94 nm和3.12 nm,它们都能以能量转移的方式与BSA发生作用。紫外-可见光谱、同步荧光光谱和三维荧光光谱的研究结果表明,棉酚及其氧化物与BSA的结合引起了BSA的构象变化。 相似文献
109.
Martina Rejtharová Libor Rejthar Katarína Čačková 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(2):233-240
A sensitive and robust confirmatory method for determination of steroid esters in blood serum is essential for reliable monitoring of possible illegal use of steroid hormones as growth promoters in meat production. A previously used sample preparation methodology was improved. The procedure consists of protein precipitation and removal of phospholipids by dispersive SPE Supel? QuE Z-Sep (Sigma-Aldrich) followed by clean-up on alumina column and LC-MS/MS measurement. The modified method has been validated according to Commission Decision 2002/657/EC. Validation parameters for determination of six testosterone esters and five nortestosterone esters in bovine and porcine blood serum are presented in this article. Decision limits for all analytes were observed in the range 10–20 pg mL?1. The method described is considerably robust for bovine and porcine serum analyses and can be applied both for screening and confirmatory determination in routine residue monitoring. 相似文献
110.
Rider A Perez-Maldonado Barry W Norton Graham L Kerven 《Journal of the science of food and agriculture》1995,69(3):291-298
In interaction of condensed tannins from Desmodium intortum and Lotus pedunculatus and tannic acid (hydrolysable tannin) with salivary mucoproteins (from sheep and goats), plant leaf proteins and bovine serum albumin were evaluated. These studies were carried out over a pH range of 2-0-9-0 and different inorganic ion conditions to simulate conditions in which dietary proteins would interact with tannins in a ruminant digestive tract. Insoluble tannin-protein interactions were found at pH 4–5–5–5 for bovine serum albumin and 3–5–5–5 for plant leaf protein. The present study showed that pH alone was not the sole determinant for tannin-protein complex formation, since tannin-protein complexation was found in the pH range 6-0–6-5 when different inorganic ions were added to the solutions. Insoluble complexes were not formed with salivary proteins, although precipitation by tannic acid was achieved at 5°C. This suggests that tannins may form soluble rather than insoluble complexes with salivary proteins. It was concluded that purified F1 leaf protein (the major protei occurring in leaf tissue) ought to be used as the test protein for evaluating tannin-protein interactions for in vitro assay procedures. Using this method it was calculated that 27–43% and 19–40% of available plant protein may interact with condensed tannins from Desmodium intortum and Lotus pedunculatus, respectively. 相似文献