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91.
Dai Kato Atsumu Oda Mutsuo Tanaka Seiichiro Iijima Tomoyuki Kamata Masami Todokoro Yasuo Yoshimi Osamu Niwa 《Electroanalysis》2014,26(3):618-624
We developed an electrochemical system for detecting lipopolysaccharide (LPS) that uses an ultraflat nanocarbon film electrode modified with poly‐ε‐lysine with a high affinity to LPS. LPS was captured on the modified electrode, and then ferrocene labeled polymyxin B (FcPMB) was captured on the LPS adsorbed electrode via the LPS‐PMB affinity interaction. The adsorbed FcPMB provided an amplified response with Fe2+ ions, and the current response was dependent on the amount of captured LPS (LOD=2.0 ng/mL). This was due to the efficient accumulation of the obtained current for LPS and the very low noise made possible by the ultraflat surface. 相似文献
92.
抗坏血酸是许多生化过程所必需的一种生物小分子。借助于羟基氧化钴纳米片的氧化性和钴离子与硫氰酸根离子之间强的螯合作用,本研究首次报道了一种基于钴离子信号转换的新方法用于抗坏血酸的比色分析。在抗坏血酸存在时,羟基氧化钴纳米片被还原降解产生二价钴离子,钴离子与硫氰酸根离子之间通过螯合作用生成蓝色的[Co(NCS)4]2-阴离子络合物,在625 nm处产生可见吸收信号。实验首先对羟基氧化钴纳米片与抗坏血酸的反应时间、硫氰酸铵和吐温-80的加入量等实验参数进行了优化,当反应时间为5 min,硫氰酸铵(3 mol/L)和吐温-80(10%, w%)的加入体积分别为30 μL和80 μL时,检测体产生最强的吸收信号。在优化的条件下,随着抗坏血酸浓度的增加,检测体系在625 nm处的吸收值线性增强,在0.03~0.45 mmol/L浓度范围内,检测体系在625 nm处的吸收值与AA浓度呈良好的线性关系,线性方程为A625=0.638C (mmol/L)+0.042,相关系数R=0.993,检测限(3S/N)为1.5 μmol/L。 相似文献
93.
In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplification methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented. 相似文献
94.
Recent advancement in nanoscience and nanotechnologies inspired a wide spectrum of uses of nanodimensional materials ranging from industrial sector to biomedical applications. Inorganic nanomaterials made of noble metals, which are corrosion-resistant, are often included as electrode modifiers in designing electrochemical chemosensors and biosensors because of their unique catalytic, electric, and surface-related properties. This review summarizes the developments in electrochemical biosensors with integrated in their architecture metal nanostructures reported mainly during the last two years with a summary on some of the commonly used methods for the synthesis of metallic nanostructures. Nanodimensional noble metal structures might be considered as multipurpose electrode modifiers because of their abilities to act at the same time as electrocatalysts, signal amplifiers, and tools for immobilization and spatial orientation of redox proteins/enzymes or other type of bioreceptors. 相似文献
95.
96.
本文着重论述了田口式参数设计法在半导体制造中对线宽的质量控制.通过田口式参数设计法,可以优化线宽控制对光刻过程步骤中的可控参数的条件,以便将不可控因素的影响降到最低. 相似文献
97.
随着5G商用牌照的发放,5G基站建设如火如荼地开展,5G基站的基础配套的改造需求变得越来越紧迫.现有基站的配套能力如何满足5G建设的需要,成为亟需面对和解决的问题.通过分析三大运营商5G网络的特点和架构,同时考虑多家运营商共享情况,并根据5G网络建设实施情况分析5G基站的塔桅抱杆、电源和外电的配套改造方案. 相似文献
98.
99.
《Physics letters. A》2020,384(15):126307
We introduce a procedure for separating periodic oscillations superposed on a stochastic signal. The procedure combines empirical mode decomposition (EMD) of a signal with tools of data analysis based on stochastic differential equations, namely nonlinear Langevin equations. Taking the set of modes retrieved from the EMD of the signal, our procedure is able to separate them into two groups, one composing the periodic signal and another composing the stochastic signal. The framework is robust for a broad family of localized oscillations, in the range of large frequencies. In particular, we show that, in this context, the EMD method outperforms a low-pass filter and is robust for a wide interval of different frequency ranges and amplitudes of the periodic oscillation, as well as for a broad family of different non-linear Langevin processes. 相似文献
100.