新型巯基化合物自组装膜修饰电极对铜离子的检测

合成了一种新型的巯基化合物,在金电极上形成自组装膜,以循环伏安法和电化学阻抗法(EIS)对自组装膜进行表征,基于其末端的氨基对铜离子的配位效应,实现了对铜离子的快速检测,并优化了沉积时间、pH、静止时间、沉积电压等检测条件.同时研究了铜离子与人血清白蛋白的相互作用.结果表明,该组装膜在2×10-7 ～2.5×10-3 mol/L范围内对铜离子有线性响应,检出限为0.05 μmol·L-1,其与蛋白的结合常数为2.20×103 L/mol.银离子、锌离子等对铜离子的测定几乎没有干扰.     

巯基化合物分离富集技术的应用进展

根据负载(或鳌合)巯基的物质不同,分别对巯基棉、巯基葡聚糖凝胶、巯基纸、巯基活性炭和巯基树脂等分离富集剂的制备、应用及机理进行了综述。     

巯基化合物在分析中的应用

本文评述了巯基化合物在分析中的应用。叙述了其在一般的元素分析以及接着在各种吸附剂或电极的表面制得巯基吸附剂或巯基修饰电极从而用来富集测定微量元素的进展情况，引用文献达２２０篇。     

巯基化合物近红外小分子荧光试剂的研究进展

巯基化合物(RSH)广泛存在于生物体内,在生命活动中起着关键作用。因此,检测其含量变化及动态分布十分必要。近红外(NIR,600nm)荧光由于背景干扰少、组织穿透力强、对生物损伤小等特点日益成为人们关注的焦点,而有机小分子荧光试剂在近红外荧光分析中的应用较多。本文引用文献94篇,按有机小分子的荧光团分类,对2010年以来用于巯基化合物分析的有机小分子荧光试剂进行了综述,并展望了其发展趋势和应用前景。     

生物小分子巯基化合物荧光探针研究进展

细胞内的小分子巯基化合物在诸多生理过程中扮演重要角色.分子荧光探针具有灵敏度高、选择性好、生物相容性好、实时原位监测等优点.因此,构建可以选择性检测巯基化合物的荧光探针具有重要的生物学和医学意义.根据荧光探针与巯基化合物的反应类型总结了近几年来小分子巯基化合物荧光探针的设计策略和研究进展.     

巯基化合物的电位分析法研究

本文对用直接电位法测试巯基化合物的可行性进行了研究。发现由硫化银，硫化汞等金属难溶盐制成的膜电极对６－巯基嘌呤，高胱氨酸，１，４－二巯基苏糖经合物可产生响应，其斜率为３０－１１０ｍＶ／ｐＣ，电极响应时间，则为十几秒至十几分钏，测试结果具有较好的重现性。因此，该方法可望得到应用。文中还对有关响应机理进行了探讨。     

逐层自组装修饰金电极

巯基羧酸吸在金电极表面形成自组装置单分子层，其中巯基与金共价结合，而裸露在表面的羧基可用于进一步修饰，用逐层反应的方法，可通过乙二胺将二茂铁羧酸结合在自组装单分子层上，电极的行为用电化学表征。     

基于双氢青蒿素-巯基化合物电化学探针对巯基化合物的检测

在20%乙醇+B-R缓冲溶液(pH7.2)介质中,利用双氢青蒿素与谷胱甘肽、6-巯基嘌呤及L-半胱氨酸作用,分别于-1.05,-1.20和-1.10V处获得双氢青蒿素-巯基化合物复合物灵敏的还原峰,该还原峰在一定浓度范围内随着巯基化合物以及双氢青蒿素浓度的增加而增大,因此可将其作为电化学探针应用于上述3种巯基化合物以及双氢青蒿素的检测,为检测巯基化合物提供了一种新方法;探讨了复合物形成的电极反应机理,利用纳米金与巯基的共价作用阻断巯基参与形成复合物,证实了复合物是由双氢青蒿素中的碳自由基与巯基化合物巯基中的硫原子通过SC键结合形成。     

快速检测巯基化合物的新方法

本文利用巯基化合物对异硫氰酸荧光素(FITC)的荧光猝灭作用,建立了一种快速检测巯基化合物的新方法。实验中发现,巯基化合物能够猝灭FITC的荧光,据此发展了检测巯基化合物的新方法。本方法的用时非常短,在优化了pH、反应时间等条件后能在5min之内完成对巯基化合物的检测。在最佳条件下对实际样品的测试取得了很好的效果,且具有良好的选择性。对谷胱甘肽(GSH)、高半胱氨酸(Hcy)、半胱氨酸(Cys)、二硫苏糖醇(DTT)的检测限分别达到3.08、2.66、1.28和1.92μmol/L。     

巯基卟啉自组装膜的制备及应用研究进展

详细介绍了巯基卟啉自组装膜的几种制备方法,评述了不同制备方法的优缺点;对卟啉自组装膜在电荷转移、分子氧电催化、分子光电器件等领域的研究进展进行了评述,引用文献54篇。     

Supramolecular Enhancement of Charge Transport through Pillar[5]arene-Based Self-Assembled Monolayers

Intermolecular charge transport is one of the essential modes for modulating charge transport in molecular electronic devices. Supermolecules are highly promising candidates for molecular devices because of their abundant structures and easy functionalization. Herein, we report an efficient strategy to enhance charge transport through pillar[5]arene self-assembled monolayers (SAMs) by introducing cationic guests. The current density of pillar[5]arene SAMs can be raised up to about 2.1 orders of magnitude by inserting cationic molecules into the cavity of pillar[5]arenes in SAMs. Importantly, we have also observed a positive correlation between the charge transport of pillar[5]arene-based complex SAMs and the binding affinities of the pillar[5]arene-based complexation. Such an enhancement of charge transport is attributed to the efficient host–guest interactions that stabilize the supramolecular complexes and lower the energy gaps for charge transport. This work provides a predictive pattern for the regulation of intermolecular charge transport in guiding the design of next generation switches and functional sensors in supramolecular electronics.     

Self-Assembled Monolayers of N-Heterocyclic Olefins on Au(111)

Self-assembled monolayers (SAMs) of N-heterocyclic olefins (NHOs) have been prepared on Au(111) and their thermal stability, adsorption geometry, and molecular order were characterized by X-ray photoelectron spectroscopy, polarized X-ray absorption spectroscopy, scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The strong σ-bond character of NHO anchoring to Au induced high geometrical flexibility that enabled a flat-lying adsorption geometry via coordination to a gold adatom. The flat-lying adsorption geometry was utilized to further increase the surface interaction of the NHO monolayer by backbone functionalization with methyl groups that induced high thermal stability and a large impact on work-function values, which outperformed that of N-heterocyclic carbenes. STM measurements, supported by DFT modeling, identified that the NHOs were self-assembled in dimers, trimers, and tetramers constructed of two, three, and four complexes of NHO−Au-adatom. This self-assembly pattern was correlated to strong NHO−Au interactions and steric hindrance between adsorbates, demonstrating the crucial influence of the carbon-metal σ-bond on monolayer properties.     

Self-Assembled Monolayers of Bi-Functionalized Porphyrins: A Novel Class of Hole-Layer-Coordinating Perovskites and Indium Tin Oxide in Inverted Solar Cells

Self-assembled monolayers (SAMs) offer the advantage of facile interfacial modification, leading to significant improvements in device performance. In this study, we report the design and synthesis of a new series of carboxylic acid-functionalized porphyrin derivatives, namely AC-1, AC-3, and AC-5, and present, for the first time, a strategy to exploit the large π-moiety of porphyrins as a backbone for interfacing the indium tin oxide (ITO) electrode and perovskite active layer in an inverted perovskite solar cell (PSC) configuration. The electron-rich nature of porphyrins facilitates hole transfer and the formation of SAMs, resulting in a dense surface that minimizes defects. Comprehensive spectroscopic and dynamic studies demonstrate that the double-anchored AC-3 and AC-5 enhance SAMs on ITO, passivate the perovskite layer, and function as conduits to facilitate hole transfer, thus significantly boosting the performance of PSCs. The champion inverted PSC employing AC-5 SAM achieves an impressive solar efficiency of 23.19 % with a high fill factor of 84.05 %. This work presents a novel molecular engineering strategy for functionalizing SAMs to tune the energy levels, molecular dipoles, packing orientations to achieve stable and efficient solar performance. Importantly, our comprehensive investigation has unraveled the associated mechanisms, offering valuable insights for future advancements in PSCs.     

Surface and antimicrobial properties of semi-fluorinated quaternary ammonium thiol surfactants potentially usable for Self-Assembled Monolayers

The surfactant and antimicrobial activities of thiol and disulfide derivatives containing a quaternary ammonium group bearing variable perfluorinated carbon chains via an amide connector between the sulfur and nitrogen atoms were evaluated with the future aim to be grafted on metal surfaces for obtaining contact-active and non-adhesive auto-biocidal surfaces. Their biostatic and bactericidal activities against four microbial strains (Pseudomonas aeruginosa, Staphylococcus aureus, Aspergillus niger and Candida albicans) were measured. The presence of the thiol, disulfide and amide functions in these surfactants were discussed in relation with antimicrobial activity along with the influence of the length of fluorinated chains in order to determine which molecular parameters are ‘critical’ for biological activity.     

Pragmatic Studies on Protein-Resistant Self-Assembled Monolayers

Summary. The present study describes new synthetic routes to oligo(ethylene glycol)-terminated alkanethiols (OEG-ATs), starting from α,ω-dibromoalkanes, which are reacted either with OEG or with trityl mercaptan in the first step. In addition to these ether conjugates of OEG and AT, analogous ester and amide conjugates were prepared by established procedures. All thiols were used to form self-assembled monolayers (SAMs) on cleaned gold surfaces and these were stored for 1–2 weeks under water at 4°C before the extent of nonspecific protein adsorption was tested with IgG, BSA, and lysozyme at 1 mg cm⁻³ protein concentration in phosphate-buffered saline. Under these practice-oriented testing conditions, SAMs with tri(ethylene glycol) chains (EG ₃) exhibited nonsatisfactory protein resistance, in sharp contrast to EG ₄ or longer OEG chains. The effectiveness of EG ₃ was partially restored when they were linked to a long acyl chain (16-mercaptohexadecanoic acid) instead of 12-mercaptododecane or 11-mercaptoundecane. Furthermore it was found that (i) SAM formation at 20 μM thiol versus 500 μM OEG-AT gave identical results, (ii) gel-filtered proteins were much less adsorbed than the unpurified commercial products, and (iii) the method for gold-precleaning was very critical. In conclusion, this study offers convenient synthetic routes to OEG-AT and helps to choose molecules and procedures for reliable preparation of protein-resitant SAMs with prolonged stability during storage.     

Photoactivated Preparation and Patterning of Self-Assembled Monolayers with 1-Alkenes and Aldehydes on Silicon Hydride Surfaces

Direct lateral patterning in the formation of self-assembled monolayers (SAMs) on silicon was achieved by the photoinduced reaction of aldehydes with Si(111)-H surfaces by using the usual masking techniques (see the schematic illustration; on the right-hand side is a microscopy image of a patterned SAM formed from octadecanal).     

自组装单层膜的制备与应用

本文综述了自组装单层膜制备及应用技术的最新发展,分别对有机硅烷/羟基化表面和硫醇/金两种重要的自组装单层膜体系的制备新技术以及在制膜技术和分子电子学等领域的最新应用进行了总结.     

An STM Study of Chemically Deposited Silver Nanoclusters on Mixed Self-Assembled Monolayers

Small silver clusters Ag _n (primarily probably Ag₄ clusters which aggregate to Ag_n (400<n<2000)) are generated in the immediate vicinity of a four-electron reducing agent (based on hydroquinone) which is incorporated in a monolayer of long-chain alkanethiols. The hydroquinone derivative is oxidized to quinone (see the picture). Molecularly resolved scanning tunneling microscopy (STM) images were obtained of self-assembled monolayers with and without silver clusters.     

高覆盖率氟代癸基三氯硅烷自组装单分子膜的制备

通过液相沉积在云母表面制备1H, 1H, 2H, 2H-全氟癸基三氯硅烷(FDTS)自组装单分子膜(SAMs)。室温下,将1.0 mmol·L^-1的FDTS溶液静置水解15 min,再把云母浸入自组装30 min,原子力显微镜(AFM)表征发现,液相沉积过程中FDTS的团聚现象得到有效解决。该方法制备出了高覆盖率(85% ± 2%)和低均方根粗糙度(0.58 nm)的FDTS SAMs,且单分子膜的生长过程符合Langmuir一级动力学吸附模型。在液相沉积过程中,若水解和组装同时进行,过长的水解时间(大于30 min)或组装时间(大于30 min)均会导致FDTS的团聚,进而极大降低SAMs的质量。