Determination of Critical Micellar Concentration of Homologous 2-Alkoxyphenylcarbamoyloxyethyl-Morpholinium Chlorides

Autor: Lenka Stopková, Jana Gališinová, Zuzana Šuchtová, Jozef Čižmárik, Fils Andriamainty
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Molecules, Vol 23, Iss 5, p 1064 (2018)
Druh dokumentu: article
ISSN: 1420-3049
DOI: 10.3390/molecules23051064
Popis: The critical micellar concentrations of selected alkyloxy homologues of local anesthetic 4-(2-{[(2-alkoxyphenyl)carbamoyl]oxy}ethyl)morpholin-4-ium chloride with nc = 2, 4, 5, 6, 7, 8, and 9 carbons in alkyloxy tail were determined by absorption spectroscopy in the UV–vis spectral region with the use of a pyrene probe. Within the homologous series of the studied amphiphilic compounds, the ln(cmc) was observed to be dependent linearly on the number of carbon atoms nc in the hydrophobic tail: ln(cmc) = 0.705–0.966 nc. The Gibbs free energy, necessary for the transfer of the methylene group of the alkoxy chain from the water phase into the inner part of the micelle at the temperature of 25 °C and pH ≈ 4.5–5.0, was found to be −2.39 kJ/mol. The experimentally determined cmc values showed good correlations with the predicted values of the bulkiness of the alkoxy tail expressed as the molar volume of substituent R, as well as with the surface tension of the compounds.
Databáze: Directory of Open Access Journals
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