Ion transport in nanopores

Chun, K.-Y. Stroeve, P External Control of Ion Transport in Nanoporous Membranes with Surfaces Modified with Self-Assembled Monolayers. Langmuir 17, 5271-5275 (2001). 

Electroosmotic flow Ioti conductance in nanochannels Ion transport in nanopores Nanopore conductance... 

Electrokinetic Flow and Ion Transport In Nanochannels, Figure 4 A sequence of four frames (movie available on the online version of this volume) from a MD simulation movie showing a single stranded DNA molecule being pulled through an alpha Hemolysin nanopore by the application of an electric field [13]... 

Since UTCLs contain no added electrolyte, the mode of proton transport in such layers remains a debated question. It was postulated in Chan and Eikerling (2011) that protons in water-filled UTCL pores undergo bulk-water-like transport, similar to ion transport in charged nanofluidic channels (Daiguji, 2010 Stein et al., 2004) and gold nanoporous membranes (Nishizawa et al., 1995). The proton conductivity of the pore is then determined by the electrostatic interaction of protons with the surface charge of pore walls. 

Tim Albrecht, Marco Carminati, Giorgio Ferrari, Philippa Nuttall, William Pitchford and Agnieszka J. Rutkowska An introduction to nanopore sensing Ion and fluid transport in nanopore channels Low noise electronics for nanopore sensors Experimental impedance characterisation of solid-state nanopore sensors... 

Metal microtubules were prepared in a similar marmer, with lower internal diameters of 0.8 nm, and the authors could demonstrate that ion transport through such tubules can be switched from positive to negative ions with external potentials applied to the membrane. 2 Gold nanowires (of as little as 10 nm diameter) deposited in nanoporous filtration disks can also act as nanoelectrodes with sensitive cyclic voltammetric detection limits. Finally, the template membrane approach has also been extended to arrays of cadmium chalcogenide phases. Thus, 200 nm-diameter CdSe or graded CdSe/CdTe cylinders were electrodeposited in the pores of Anopore membranes. A Ni-CdSe array was found to be rectifying.i ... 

All of the above features make silica colloidal crystals ideal candidates for highly selective responsive nanoporous membranes. However, until 2005, there were no publications describing transport through surface-modified colloidal membranes. In 2005, Zharov group introduced, for the first time, the concept of permselective colloidal nanoporous membranes by describing pH-responsive amine-modified colloidal membranes with controlled transport of positively charged species [26]. Later, they reported a detailed study of transport through amine-modified colloidal membranes [27], as well as membranes modified with sulfonic acids [28,29], Methods to modify the colloidal nanopores with polymers were developed [30], which allowed us to introduce temperature-responsive poly(A-isopropylacrylamide) (PNIPAAM) [31], pH- and ion-responsive poly(2-(dimethylamino)ethyl methacrylate), PDMAEMA [32], and pH- and temperature-responsive poly(L-alanine) [33], and to study the molecular transport in these polymer-modified nanoporous coUoidal membranes as a function of the environmental conditions. In this chapter we summarize these results. 

Siwy, Z. Apel, P. Dobrev, D. Neumann, R. Spohr, R. Trautmann, C. Voss, K., Ion transport through asymmetric nanopores prepared by ion track etching. Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms 2003, 208, 143-148. 

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