Titration of fatty acids in sugar-derived (APG) surfactants: A C-13 NMR study of the effect of headgroup size, chain length, and concentration on fatty acid pKa at a nonionic micellar interface
(2003) In The Journal of Physical Chemistry Part B 107(4). p.1001-1005- Abstract
- The pK(a) of a C-13-enriched fatty acid probe, tetradecanoic acid, was investigated in a variety of sugar-derived (APG) surfactants by using C-13 NMR to monitor the chemical environment of the probe during titration with base. There was an increase of approximately 2 pK(a) units for the probe within the micellar systems compared to the value of acetic acid in water. Analysis shows that the interfacial environment of alkylglucoside surfactants is similar to, although slightly more polar than, that of ethylene glycol-derived (EO) nonionic surfactants, and there is no indication that the alkylglucoside surfactants are deprotonated at pH levels between 2 and 10. The average pK(a) of the fatty acid probe in the APGs is measured to be 6.3, and... (More)
- The pK(a) of a C-13-enriched fatty acid probe, tetradecanoic acid, was investigated in a variety of sugar-derived (APG) surfactants by using C-13 NMR to monitor the chemical environment of the probe during titration with base. There was an increase of approximately 2 pK(a) units for the probe within the micellar systems compared to the value of acetic acid in water. Analysis shows that the interfacial environment of alkylglucoside surfactants is similar to, although slightly more polar than, that of ethylene glycol-derived (EO) nonionic surfactants, and there is no indication that the alkylglucoside surfactants are deprotonated at pH levels between 2 and 10. The average pK(a) of the fatty acid probe in the APGs is measured to be 6.3, and it is argued that this value
s an appropriate choice for pK(a)(0), the intrinsic dissociation constant for an acid at a hydrophobic/hydrophilic interface, when calculating the surface potential of charged systems. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/122271
- author
- Whiddon, Christy LU ; Bunton, C A and Söderman, Olle LU
- organization
- publishing date
- 2003
- type
- Contribution to journal
- publication status
- published
- subject
- in
- The Journal of Physical Chemistry Part B
- volume
- 107
- issue
- 4
- pages
- 1001 - 1005
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000180649100016
- scopus:0037473032
- ISSN
- 1520-5207
- DOI
- 10.1021/jp0263875
- language
- English
- LU publication?
- yes
- id
- ac030ea8-c97e-4171-8df1-3a1ac80baf18 (old id 122271)
- date added to LUP
- 2016-04-01 17:12:23
- date last changed
- 2022-01-29 01:06:20
@article{ac030ea8-c97e-4171-8df1-3a1ac80baf18,
abstract = {{The pK(a) of a C-13-enriched fatty acid probe, tetradecanoic acid, was investigated in a variety of sugar-derived (APG) surfactants by using C-13 NMR to monitor the chemical environment of the probe during titration with base. There was an increase of approximately 2 pK(a) units for the probe within the micellar systems compared to the value of acetic acid in water. Analysis shows that the interfacial environment of alkylglucoside surfactants is similar to, although slightly more polar than, that of ethylene glycol-derived (EO) nonionic surfactants, and there is no indication that the alkylglucoside surfactants are deprotonated at pH levels between 2 and 10. The average pK(a) of the fatty acid probe in the APGs is measured to be 6.3, and it is argued that this value <br/><br>
s an appropriate choice for pK(a)(0), the intrinsic dissociation constant for an acid at a hydrophobic/hydrophilic interface, when calculating the surface potential of charged systems.}},
author = {{Whiddon, Christy and Bunton, C A and Söderman, Olle}},
issn = {{1520-5207}},
language = {{eng}},
number = {{4}},
pages = {{1001--1005}},
publisher = {{The American Chemical Society (ACS)}},
series = {{The Journal of Physical Chemistry Part B}},
title = {{Titration of fatty acids in sugar-derived (APG) surfactants: A C-13 NMR study of the effect of headgroup size, chain length, and concentration on fatty acid pKa at a nonionic micellar interface}},
url = {{http://dx.doi.org/10.1021/jp0263875}},
doi = {{10.1021/jp0263875}},
volume = {{107}},
year = {{2003}},
}