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51.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献
52.
《Electrophoresis》2017,38(3-4):507-512
LIF detection often requires labeling of analytes with fluorophores; and fast fluorescent derivatization is valuable for high‐throughput analysis with flow‐gated CE. Here, we report a fast fluorescein‐labeling scheme for amino acid neurotransmitters, which were then rapidly separated and detected in flow‐gated CE. This scheme was based on the reaction between primary amines and o‐phthalaldehyde in the presence of a fluorescent thiol, 2‐((5‐fluoresceinyl)aminocarbonyl)ethyl mercaptan (FACE‐SH). The short reaction time (<30 s) was suited for on‐line mixing and derivatization that was directly coupled with flow‐gated CE for rapid electrophoretic separation and sensitive LIF detection. To maintain the effective concentration of reactive FACE‐SH, Tris(2‐carboxyethyl)phosphine was added to the derivatization reagents to prevent thiol loss due to oxidation. This labeling scheme was applied to the detection of neurotransmitters by coupling in vitro microdialysis with online derivatization and flow‐gated CE. It is also anticipated that this fluorophore tagging scheme would be valuable for on‐chip labeling of proteins retained on support in SPE. 相似文献
53.
《Electroanalysis》2017,29(8):1840-1849
The integration of biomolecular logic principles with electronic transducers allows designing novel digital biosensors with direct electrical output, logically triggered drug‐release, and closed‐loop sense/act/treat systems. This opens new opportunities for advanced personalized medicine in the context of theranostics. In the present work, we will discuss selected examples of recent developments in the field of interfacing enzyme logic gates with electrodes and semiconductor field‐effect devices. Special attention is given to an enzyme OR/Reset logic gate based on a capacitive field‐effect electrolyte‐insulator‐semiconductor sensor modified with a multi‐enzyme membrane. Further examples are a digital adrenaline biosensor based on an AND logic gate with binary YES/NO output and an integrated closed‐loop sense/act/treat system comprising an amperometric glucose sensor, a hydrogel actuator, and an insulin (drug) sensor. 相似文献
54.
David C. Magri 《Supramolecular chemistry》2017,29(10):741-748
AbstractFrom the cross-fertilisation of fluorescent pH indicators and fluorescent redox switches, our group has established a new class of molecular sensor that operates as two-input molecular logic gates. These molecular sensors, known as ‘Pourbaix sensors’, are named in honour of Marcel Pourbaix, who developed the pH–potential diagrams for the various states of metal ion species in aqueous solution. This review highlights the evolution of ‘Pourbaix sensors’ based on anthracene and naphthalimide fluorophores. Potential applications of this class of molecule in fields such as corrosion science, cell biology and biomedical diagnostics are highlighted. 相似文献
55.
56.
“门控制”效应分子印迹传感器测定绿麦隆 总被引:1,自引:0,他引:1
在氧化铂电极表面采用化学聚合法制得绿麦隆分子印迹膜传感器。利用"门控制"中"门"的数量变化控制催化性能的强弱,结合氧化铂对过氧化氢的催化放大效应,有效的提高了传感器的灵敏度并建立了对环境中绿麦隆残留的检测方法。研究了氧化铂电极对过氧化氢的催化效果,并对分子印迹膜聚合配比、过氧化氢浓度、洗脱时间、重吸附时间进行优化。在优化条件下,绿麦隆浓度在1.0×10-88.0×10-6mol/L范围内与氧化铂电极对过氧化氢的催化电流呈负相关性,检出限为5.4×10-9moL/L。该传感器成功应用于农田水样的检测,其回收率为98.5%102.0%。 相似文献
57.
本工作利用圆二色光谱研究了Ag+与Hg2+对4种代表性G-四链体DNA结构的破坏作用。结果表明Ag+可能通过与碱基G螯合从而破坏G-四链体结构;Hg2+能通过形成T-Hg2+-T碱基对,及其他方式破坏G-四链体结构。含巯基(-SH)的半胱氨酸与Ag+与Hg2+可以发生较强的配位作用,从而使被Ag+与Hg2+破坏后的G-四链体DNA结构得以回复。基于此,一个新颖的Ag+/Hg2+-半胱氨酸-DNA逻辑门得以构筑。 相似文献
58.
Results of an investigation of in situ measurements of laser‐beam intensity Is and Im transmitted through aqueous ammonium dihydrogen phosphate (ADP) solutions saturated at 30 °C and water, respectively, and temperature Ts of solution and Tm of water during feeding of antisolvent acetone at different rates RA, using an indigenously designed experimental setup, are presented and discussed. It was found that: (1) for the measurement of MSZW, defined as the maximum volume fraction of acetone content Δxmax in the solution, obtained from temperature measurements are more reliable than transmitted laser‐beam intensity measurements for solutions, (2) two minima ΔTmin1 and ΔTmin2 associated with endothermic reactions, separated by a maximum ΔTmax due to exothermic reactions appear in the plots of temperature difference ΔT = Ts−Tm against acetone feeding time t, and (3) in the ΔT(t) plots there are time intervals Δt of constant rates RT of increase in ΔT of aqueous ADP solutions, and these values of RT increase linearly with acetone feeding time rate RA. The experimental data on the observed dependence of MSZW on antisolvent feeding rate RA, the appearance of minima ΔTmin1 and ΔTmin2 and maximum ΔTmax and their dependence on RA, and the relationship between RT and RA are discussed from consideration of processes of nucleation and growth of crystallites. 相似文献
59.
We study the influence of multi-photon processes on the geometric quantum computation in the systems of superconducting qubits based on the displacement-like and the general squeezed operator methods. As an example, we focus on the question about how to implement a two-qubit geometric phase gate using superconducting circuit quantum electrodynamics with both single- and two-photon interaction between the qubits and the cavity modes. We find that the multiphoton processes are not only controllable but also improve the gating speed. The comparison with other physical systems and experimental feasibility are discussed in detail. 相似文献
60.
湍流大气中斜程传输部分相干光的光束扩展 总被引:4,自引:1,他引:3
运用维格纳分布函数与广义惠更斯菲涅耳原理,推导出部分相干光束在任意折射率起伏功率谱模型的大气湍流中斜程传输时,其束宽传输的一般解析表达式。在此基础上,以部分相干平顶(PCFT)光束为例,给出了PCFT光束在大气湍流中斜程传输的束宽扩展解析表达式。在合肥地区大气折射率结构常数高度分布模式下开展了数值计算和分析,并与水平传输时的结果进行了比较。研究结果表明,光束在斜程传输时的束宽不仅与光束阶数、空间相干度、束腰半径、湍流的强弱和传输距离有关,还与天顶角密切相关。光束的阶数越高,空间相干性越差,天顶角越小,则其束宽扩展受湍流的影响就越小。当天顶角小于60°时,大气湍流对斜程传输光束束宽的影响明显小于水平传输的情况。 相似文献