Prussian Blue/Multiwalled Carbon Nanotube Hybrids: Synthesis,Assembly and Electrochemical Behavior

Prussian blue/carbon nanotube (PB/CNT) hybrids with excellent dispersibility in aqueous solutions were synthesized by adding CNTs to an acidic solution of Fe³⁺, [Fe(CN)₆]^3? and KCl. Fourier transform infrared spectroscopy, UV‐vis absorption spectroscopy and scanning electron microscopy were employed to confirm the formation of PB/CNT hybrids. The PB nanoparticles formed on the CNT surfaces exhibit a narrow size distribution and an average size of 40 nm. The present results demonstrate that the selective reduction of Fe³⁺ to Fe²⁺ by CNTs is the key step for PB/CNT hybrid formation. The subsequent fabrication of the PB/CNT hybrid films was achieved by layer‐by‐layer technique. The thus‐prepared PB/CNT hybrid films exhibit electrocatalytic activity towards H₂O₂ reduction.     

普鲁士蓝/壳聚糖杂化膜修饰氧化锌球腔阵列/氧化铟锡电极制备及应用

用Langmuir-Blodgett技术制成了附着聚苯乙烯小球的氧化铟锡(InSnO)模板。将此模板水平置于由硝酸锌及柠檬酸组成的前驱体溶胶中,用溶胶-凝胶法制得氧化锌球腔阵列/氧化铟锡电极。采用电沉积法得到普鲁士蓝/壳聚糖杂化膜修饰的氧化锌球腔阵列/氧化铟锡电极。该电极在pH 7.0～8.0的溶液中具有良好的电化学活性,过氧化氢浓度在7.67×10-7～4.72×10-4mol.L-1范围内与相应的电流响应值呈线性关系,检出限(3S/N)为2.4×10-7mol.L-1。测定2.0×10-5mol.L-1过氧化氢溶液时,其相对标准偏差(n=10)为3.8%。     

基于AuNPs/PANI-NF复合膜的电化学细胞传感器对姜黄素诱导HeLa细胞凋亡的抑制作用检测

以聚苯胺纳米纤维(PANI-NF)-纳米金(AuNPs)复合膜构建传感界面,在AuNPs/PANI-NF界面上修饰转铁蛋白(Tf),利用转铁蛋白与人宫颈癌细胞(HeLa)表面大量表达的转铁蛋白受体(TfR)之间的特异性识别作用,将细胞捕获到传感器界面,导致电化学阻抗值变化。利用电化学阻抗谱研究姜黄素对HeLa细胞的抑制作用。结果表明,随着药物浓度的增大和作用时间的延长,电化学阻抗值下降,表明姜黄素对细胞的抑制作用增强。电化学阻抗值的变化率与药物浓度和作用时间具有量效关系;电化学方法检测显示,姜黄素对HeLa细胞的抑制作用趋势与MTT法及倒置显微镜检测到的姜黄素对HeLa细胞的抑制作用结果相吻合,从而建立了一种检测药物对细胞抑制作用的新方法。该方法具有简便、灵敏度高、费用低廉等优点。     

Solid-state Electrochemical Sensor Based on a Cross-linked Copper(II)-doped Copolymer and Carbon Nanotube Material for Selective and Sensitive Detection of Monohydrogen Phosphate

A novel solid-state electrochemical sensor based on a newly synthesized cross-linked copper(II) doped-copolymer and carbon nanotube material was developed for the direct determination of monohydrogen phosphate ions (HPO₄²⁻). The synthesized copolymers were characterized by FTIR, XPS, TG/DTG-DTA and SEM techniques. The sensor had a Nernstian slope:-30.7±0.4 mV/decade, linear concentrations range: 1.0×10⁻⁶ - 1.0×10⁻¹ M, detection limit: 6.5×10⁻⁷ M, response time: 4 s and life time: 17 weeks. The sensor displayed constant potentials in the pH range 7.0-9.5. The sensor was successfully used as an indicator electrode in potentiometric titration and the direct determination of HPO₄ ²⁻ in water samples.