The endothermic nature of the binding of anionic bile salts to a cationic adsorbent

Autor: Celia K Williams, G. Ronald Brown, William C. Galley
Rok vydání: 2002
Předmět:
Zdroj: Canadian Journal of Chemistry. 80:89-93
ISSN: 1480-3291
0008-4042
Popis: The binding of a hydrophobic bile salt, sodium chenodeoxycholate, by a polyacrylamide with N,N,N-trimethylammonium dodecyl chloride (QPDA12) pendant groups was studied to evaluate the thermodynamic parameters associated with the binding. The Langmuir equation was used in interpreting the data obtained from HPLC measurements. An increase in binding affinity was observed with increasing temperature indicating that the driving force for binding is derived from an increase in entropy (ΔS° = 253 J mol–1K–1) despite the positive, or unfavourable, enthalpy change (ΔH° = 53 kJ mol–1). The positive thermodynamic parameters associated with the binding suggest that the disruption of hydrophobic and (or) ionic hydration associated with the bile salts and cationic polymer is the driving force for the binding.Key words: bile salts, endothermic binding, polymer sorbents, solvent randomization.
Databáze: OpenAIRE