Designing Asymmetrically Modified Nanochannel Sensors Using Virtual EIS

We devised an approach to capture the physics of localized charge modulation and its effect on ionic transport across asymmetrically charged nanopores by combining computational and experimental strategies. A virtual EIS tool has been developed to compute the impedance across nanopores. Nanoporous anodic alumina membrane (NAA) is employed for thrombin detection with thrombin binding aptamer to experimentally validate the computed impedance results. Using the approach proposed in this work, a novel biosensor is designed and a way to enhance the sensitivity of the sensor is established.

Designing Asymmetrically Modified Nanochannel Sensors Using Virtual EIS

We devised an approach to capture the physics of localized charge modulation and its effect on ionic transport across asymmetrically charged nanopores by combining computational and experimental strategies. A virtual EIS tool has been developed to compute the impedance across nanopores. Nanoporous anodic alumina membrane (NAA) is employed for thrombin detection with thrombin binding aptamer to experimentally validate the computed impedance results. Using the approach proposed in this work, a novel biosensor is designed and a way to enhance the sensitivity of the sensor is established.

Study on Direct Current Electro-Deposition of Copper Nanowires in Anodic Alumina Membrane Pores

Aluminum alloy plays an important role in industrial applications, but has a high friction coefficient and a high wear rate. On the basis of anodic oxidation treatment on an aluminum alloy surface, copper nanowires are deposited into the anodic alumina membrane pores by direct current (DC) electrolytic treatment to prepare a composite alumina membrane, which significantly improves the tribological properties of the aluminum alloy surface. In this process, in order to obtain a highly-ordered nanoporous alumina membrane with a thin enough barrier layer for further processing, after the first anodic oxidation in phosphoric acid (0.3 mol/L), the obtained alumina membrane is modified by anodizing it in a phosphoric acid-ammonium hexafluorosilicate bath, in combination with a step-by-step voltage drop without oxide removal. By this method, the resistance of the modified alumina membrane is also reduced greatly, which facilitates the deposition of copper nanowires in the sulfate bath. It is found that the composite alumina membrane filled with copper nanowires has a low friction coefficient of about 0.25 and effectively improves the friction condition, giving the surface a self-lubricating property.

Fabrication and characterization of nanoporous anodic alumina membrane using commercial pure aluminium to remove coliform bacteria from wastewater

Nanoporous anodic alumina (NAA) membranes were produced by anodizing process using commercially pure aluminium (1050 alloy). The optimization of processing parameters, such as applied potential, temperature and time in two different electrolyte solutions, has been performed to produce the ordered alumina nano-membrane. Nanoporous anodic alumina membrane (NAAM) was obtained by removing the aluminium substrate and opening the bottom of the pores. The microstructure of samples was studied and analysed by field emission scanning electron microscopy (FESEM). Image processing of FESEM pictures was performed with MATLAB. The results showed that at the optimum conditions of anodizing, the percentage of porosity and ordering of pores in the samples were similar to the productions of the high purity aluminium base. NAA layers that formed in sulphuric acid solution in comparison with oxalic acid had lower pore diameter (20 nm), lower inter-pore distance (45-50 nm) and higher hardness (325HV). The optimized membranes which have been produced with the same thickness were used for separation of Coliform bacteria from the secondary clarified wastewater. The results showed that these membranes can be used as selective filters because of their desirable physical properties.