1
|
Yamauchi Y, Blonskaya IV, Apel PY. Adsorption of nonionic surfactant on porous and nonporous poly(ethylene terephthalate) films. Colloid J 2017. [DOI: 10.1134/s1061933x17050167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
2
|
Abstract
An electroless gold deposition method was used to deposit Au nanotubules within the pores of a polycarbonate template membrane. Membranes containing Au nanotubules with inside diameters of 2 and 3 nm were prepared for these studies. Thiols were chemisorbed to the inside tubule walls in order to change the chemical environment within the tubules. The effect of the chemical environment within the tubules on the transport properties of the tubule-containing membrane was investigated. Membranes modified with HS-C(16)H(33) preferentially transported hydrophobic permeant molecules. When a homologous series of permeant molecules was used, the most hydrophobic permeant was preferentially partitioned into and transported by the HS-C(16)H(33) derivatized membrane. In addition, the effect of alkyl chain length (R), in a homologous series of thiols R-SH, was investigated. Hydrophobic permeant molecules were preferentially partitioned into and transported by membranes containing the largest alkyl group. In contrast, membranes modified with HS-C(2)H(4)OH preferentially transported the more hydrophilic permeant pyridine. Finally, we show here that the HS-C(16)H(33) derivatized membrane can be used to separate hydrophobic species from hydrophilic species.
Collapse
Affiliation(s)
- K B Jirage
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | | | | |
Collapse
|
3
|
Makra I, Jágerszki G, Bitter I, Gyurcsányi RE. Nernst–Planck/Poisson model for the potential response of permselective gold nanopores. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.02.074] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
4
|
Abstract
We discuss the fabrication of gold and carbon nanotubes prepared by the template method. The gold nanotubes are prepared via electroless deposition of Au onto the pore walls of a nanoporous polycarbonate filtration membrane. Carbon nanotube membranes (CNMs) are prepared by doing chemical vapor deposition of carbon within the pores of a microporous alumina template. The pores in these filtration membranes act as templates for the nanotubes. We have shown that by controlling the Au deposition time, Au nanotubes that have effective inside diameters of molecular dimensions (<1 nm) can be prepared. These membranes are a new class of molecular sieves and can be used to separate molecules based on size. Furthermore, we describe fundamental investigations of electro osmotic flow (EOF) in carbon nanotube membranes. In addition, an electrochemical derivatization method was used to attach carboxylate groups to the nanotube walls; this enhances the anionic surface charge density, resulting in a corresponding increase in the EOF rate in the CNM.
Collapse
Affiliation(s)
- MARC WIRTZ
- Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, FL 32611, USA
| | - SCOTT A. MILLER
- Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, FL 32611, USA
| | - CHARLES R. MARTIN
- Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, FL 32611, USA
| |
Collapse
|
5
|
Sportsman KS, Bluhm EA, Abney KD. Removal of Actinides from Acidic Solution via Carrier-Mediated Facilitated Transport Across Mesoporous Substrates with Nanoengineered Surfaces: Thiol Self-Assembled Monolayers with D(tBu)ΦD(iBu)CMPO Ligands. SEP SCI TECHNOL 2011. [DOI: 10.1081/ss-200042676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- K. Scott Sportsman
- Nuclear Materials Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Elizabeth A. Bluhm
- Nuclear Materials Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Kent D. Abney
- Nuclear Materials Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| |
Collapse
|
6
|
|
7
|
Jágerszki G, Takács Á, Bitter I, Gyurcsányi RE. Solid-State Ion Channels for Potentiometric Sensing. Angew Chem Int Ed Engl 2011; 50:1656-9. [DOI: 10.1002/anie.201003849] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 10/06/2010] [Indexed: 11/09/2022]
|
8
|
|
9
|
Gardner CE, Unwin PR, Macpherson JV. Correlation of membrane structure and transport activity using combined scanning electrochemical–atomic force microscopy. Electrochem commun 2005; 7:612-8. [DOI: 10.1016/j.elecom.2005.04.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
10
|
Abstract
We have developed a new class of synthetic membranes that consist of a porous polymeric support that contains an ensemble of gold nanotubes that span the thickness of the support membrane. The support is a commercially available microporous polycarbonate filter with cylindrical nanoscopic pores. The gold nanotubes are prepared via electroless deposition of Au onto the pore walls; i.e., the pores act as templates for the nanotubes. We have shown that by controlling the Au deposition time, Au nanotubes that have effective inside diameters of molecular dimensions (<1 nm) can be prepared. These nanotube membranes can be used to cleanly separate small molecules on the basis of molecular size. Furthermore, use of these membranes as a novel electrochemical sensor is also discussed. This new sensing scheme involves applying a constant potential across the Au nanotube membrane and measuring the drop in the transmembrane current upon the addition of the analyte. This paper reviews our recent progress on size-based transport selectivity and sensor applications in this new class of membranes.
Collapse
Affiliation(s)
- Marc Wirtz
- Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, FL 32611, USA
| | | | | | | |
Collapse
|
11
|
Abstract
A combined scanning electrochemical-atomic force microscope (SECM-AFM) has been used to probe the diffusional transport of target electroactive solutes in isolated nanopores of a track-etched membrane. A polycarbonate membrane (100-nm-diam pore size) hydrated with an electrolyte solution, containing a redox-active probe molecule, such as IrCl6(3-) or Fe(phen)3(2+), functions as the model membrane system. The use of a mobile Pt-coated AFM probe enables individual solution-filled pores to be topographically identified. Analysis of the corresponding current images for the diffusion-limited oxidation of the redox mediator indicates that solution is largely confined to pores in the membrane. Moreover, the tip collector current response provides information on diffusion of the mediator through the pore. Force-distance tip approach and retract measurements allow the radius of contact between the electrochemical-AFM tip and solution confined within a pore at the point of pull-off to be estimated.
Collapse
|
12
|
Affiliation(s)
- Charles R. Martin
- Department of Chemistry and Center for Chemical Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32611
| | - Matsuhiko Nishizawa
- Department of Chemistry and Center for Chemical Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32611
| | - Kshama Jirage
- Department of Chemistry and Center for Chemical Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32611
| | - Munsik Kang
- Department of Chemistry and Center for Chemical Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32611
| |
Collapse
|
13
|
Affiliation(s)
- Hagan Bayley
- Department of Medical Biochemistry and Genetics, Texas A&M University System Health Science Center, 440 Reynolds Medical Building, College Station, Texas 77843-1114, Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, and Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32605-1200
| | | |
Collapse
|
14
|
Abstract
Two new methods of electroanalysis are described. These methods are based on membranes containing monodisperse Au nanotubules with inside diameters approaching molecular dimensions. In one method, the analyte species is detected by measuring the change in trans-membrane current when the analyte is added to the nanotubule-based cell. The second method entails the use of a concentration cell based on the nanotubule membrane. In this case, the change in membrane potential is used to detect the analyte. Detection limits as low as 10(-11) M have been achieved. Hence, these methods compete with even the most sensitive of modern analytical methodologies. In addition, excellent molecular-sized-based selectivity is observed.
Collapse
Affiliation(s)
- Y Kobayashi
- Department of Chemistry, Colorado State University, Fort Collins 80523, USA
| | | |
Collapse
|
15
|
|
16
|
Abstract
Membranes containing cylindrical metal nanotubules that span the complete thickness of the membrane are described. The inside radius of the nanotubules can be varied at will; nanotubule radii as small as 0.8 nanometer are reported. These membranes show selective ion transport analogous to that observed in ion-exchange polymers. Ion permselectivity occurs because excess charge density can be present on the inner walls of the metal tubules. The membranes reject ions with the same sign as the excess charge and transport ions of the opposite sign. Because the sign of the excess charge on the tubule can be changed potentiostatically, a metal nanotubule membrane can be either cation selective or anion selective, depending on the potential applied to the membrane.
Collapse
|
17
|
Fr�hlich HP, Woermann D. Modification of electrochemical properties of pore wall of track-etched mica membranes. Colloid Polym Sci 1986; 264:159-66. [DOI: 10.1007/bf01414843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
18
|
|
19
|
|
20
|
Quinn JA, Anderson JL, Ho WS, Petzny WJ. Model pores of molecular dimension. The preparation and characterization of track-etched membranes. Biophys J 1972; 12:990-1007. [PMID: 4339801 PMCID: PMC1484239 DOI: 10.1016/s0006-3495(72)86139-3] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Extremely uniform pores of near molecular dimension can be formed by the irradiation-etching technique first demonstrated by Price and Walker. The technique has now been developed to the stage where it can be used to fabricate model membranes for examining the various steric, hydrodynamic, and electrodynamic phenomena encountered in transport through molecular-size pores. Methods for preparing and characterizing membranes with pores as small as 25 A (radius) are described in this paper. Results on pore size determination via Knudsen gas flow and electrolyte conduction are compared. Pore wall modification by monolayer deposition is also discussed.
Collapse
|
21
|
Abstract
The hindrance effect on the aqueous diffusion rate of solutes within membrane pores of molecular size has been accurately determined. Mica membranes, 3 to 5 micrometers thick, were prepared with uniform, straight pores from 90 to 600 angstroms in diameter. With these membranes a direct estimation was possible of the interaction between pore size and molecular diffusion rates. There were no uncertainties due to wide pore size distributions or nonuniform tortuous channels as in previously used model microporous materials such as dialysis tubing or gels. Aqueous diffusion rates through these mica membranes were measured for a series of compounds with molecular diameters from 5.2 to 43 angstroms and were corrected for "liquid film resistances" adjacent to the membrane-solution interface to obtain estimates of molecular diffusivities within the micropores of the membrane. Definite evidence is presented showing that, even when molecular size is a small fraction of pore size, diffusion rates decrease markedly. The apparent reduction in solute diffusivity in the microporous membrane can be quantitatively estimated by means of the Renkin equation for hindered diffusion.
Collapse
|