The Library
Proton diffusion at phospholipid assemblies
Tools
UNSPECIFIED (2002) Proton diffusion at phospholipid assemblies. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 124 (10). pp. 2379-2383. doi:10.1021/ja012074w ISSN 0002-7863.
Research output not available from this repository.
Request-a-Copy directly from author or use local Library Get it For Me service.
Official URL: http://dx.doi.org/10.1021/ja012074w
Abstract
A new scanning electrochemical microscopy proton feedback method has been developed for investigating lateral proton diffusion at phospholipid assemblies: specifically Langmuir monolayers at the water/air interface. In this approach, a base is electrogenerated by the reduction of a weak acid (producing hydrogen) at a "submarine" ultramicroelectrode (UME) placed in the aqueous subphase of a Langmuir trough close to a monolayer. The electrogenerated base diffuses to and titrates monolayer-bound protons and is converted back to its initial form, so enhancing the current response at the UME. Local deprotonation of the monolayer creates a concentration gradient for lateral proton diffusion. A numerical model has been developed, taking into account the potential-dependent association/dissociation constant of the interfacial acid groups. A comparison is made of monolayers comprising either acidic DL-alpha-phosphatidyl-L-serine, dipalmitoyl (DPPS) or zwitterionic L-alpha-phosphatidylcholine, dipalmitoyl (DPPC) monolayers at a range of surface pressures. It is demonstrated that lateral proton fluxes at DPPS are significant, but the lateral proton diffusion coefficient is lower than in bulk solution. In contrast, lateral proton diffusion cannot be detected at DPPC, suggesting that the acid/base character of the phospholipid is important in determining the magnitude of interfacial proton fluxes.
Item Type: | Journal Article | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QD Chemistry | ||||
Journal or Publication Title: | JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | ||||
Publisher: | AMER CHEMICAL SOC | ||||
ISSN: | 0002-7863 | ||||
Official Date: | 13 March 2002 | ||||
Dates: |
|
||||
Volume: | 124 | ||||
Number: | 10 | ||||
Number of Pages: | 5 | ||||
Page Range: | pp. 2379-2383 | ||||
DOI: | 10.1021/ja012074w | ||||
Publication Status: | Published |
Data sourced from Thomson Reuters' Web of Knowledge
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |