Surface tension and UV-visible investigations of aggregation and adsorption behavior of NaC and NaDC in water-amino acid mixtures

Kumar, K; Chauhan, S

HERO ID

2953583

Reference Type

Journal Article

Year

2015

Language

English

HERO ID 2953583
In Press No
Year 2015
Title Surface tension and UV-visible investigations of aggregation and adsorption behavior of NaC and NaDC in water-amino acid mixtures
Authors Kumar, K; Chauhan, S
Journal Fluid Phase Equilibria
Volume 394
Page Numbers 165-174
Abstract Aqueous micellar solutions of bile salts, sodium cholate (NaC) (1-30 mmol kg(-1)) and sodium deoxycholate.(NaDC) (1-17 mmol kg(-1)) in the absence and presence of amino acids viz. glycine, leucine, methionine, and histidine (0.1 mol kg(-1)) have been examined by surface tension and UV-visible measurements at different temperatures (293.15-318.15 K). From the surface tension study, critical micelle concentration (CMC) values of bile salts have been calculated and reviewed in terms of effect of amino acids on the hydrophobic character of bile salt-amino acid complex. Further, the adsorption behavior of NaC and NaDC in aqueous solution of amino acids has been analyzed with the help of interfacial parameters like maximum surface excess concentration (Gamma(max)), minimum area per surfactant molecule (A(min)), surface pressure at CMC (Pi(CMC)), efficiency in reducing surface tension (pC(20)), and adsorption at the air/water interface relation to micellization (CMC/C-20). The thermodynamic parameters, standard free energy of micellization (Delta G(m)degrees), standard Gibb's free energy of adsorption (Delta G(ad)degrees), and standard free energy of transfer (Delta G(tr)degrees) have also been calculated. UV-visible studies, by using pyrene as a probe, have also been carried out in order to substantiate the CMC values derived from surface tension studies. (C) 2015 Elsevier B.V. All rights reserved.
Doi 10.1016/j.fluid.2015.03.012
Wosid WOS:000353851800018
Is Certified Translation No
Dupe Override No
Comments Scopus URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84924981357&doi=10.1016%2fj.fluid.2015.03.012&partnerID=40&md5=46555e983a91453f518ac2c2436ac8b2
Is Public Yes
Language Text English
Keyword Amino acid; Bile salt; Critical micelle concentration; Surface tension; UV-visible