Effective critical micellar concentration of a zwitterionic detergent: a fluorimetric study on n-dodecyl phosphocholine.
We have investigated the effect of ionic strength on the aggregation behavior of n-dodecyl phosphocholine. On the basis of the classical Corrin-Harkins relation, the critical micellar concentration of this detergent decreases with a biphasic trend on lithium chloride addition. It is nearly constant below 150 mM salt, with a mean value of 0.91 mM, whereas it undergoes a dramatic 80-fold decrease in 7 M LiCl. Such a drop in the critical micellar concentration could be explained by the effect of salting out and the implication of phosphocholine head groups on the organization of surrounding water. Knowledge of the effective critical micellar concentration of n-dodecyl phosphocholine could be useful in the purification of membrane proteins in non-denaturing conditions.
Palladino
Pasquale
P
Dipartimento delle Scienze Biologiche & C.I.R.Pe.B., Università Federico II, via Mezzocannone 16, 80134, Naples, Italy.
Rossi
Filomena
F
Ragone
Raffaele
R
D000817:Anilino Naphthalenesulfonates / Q000737:chemistry; D003902:Detergents / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D005470:Fluorometry; D018021:Lithium Chloride / Q000737:chemistry; D008823:Micelles; D009994:Osmolar Concentration; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry; D014867:Water / Q000737:chemistry
D000817:Anilino Naphthalenesulfonates; D003902:Detergents; D005456:Fluorescent Dyes; D008823:Micelles; D014867:Water; D010767:Phosphorylcholine; C028810:dodecylphosphocholine; C027132:1-anilino-8-naphthalenesulfonate; D018021:Lithium Chloride