The Critical Micellar Concentrations of Fatty Acyl Coenzyme A and Fatty Acyl Carnitines

Studies on the Critical Micellar Concentration and Phase Transitions of Stearoylcarnitine

“…The CMCs of fatty acyl carnitines with even acyl chain lengths between 8 and 16 carbon atoms have also been reported (Yalkowsky and Zografi 1970a, b;Requero et al 1993). Studies on the CMC of acyl CoAs and acyl carnitines have shown that under identical conditions the CMC decreases linearly with increasing acyl chain length (Smith and Powell 1986;Requero et al 1993). In addition it has been shown that the CMC values vary considerably on the properties of the medium such as buffer used, pH as well as on the method of measurement.…”

“…The effect of these two amphiphiles on the gel-fluid and lamellar-hexagonal phase transitions of phospholipids has also been investigated (Veiga et al 1996). The CMCs of fatty acyl carnitines with even acyl chain lengths between 8 and 16 carbon atoms have also been reported (Yalkowsky and Zografi 1970a, b;Requero et al 1993). Studies on the CMC of acyl CoAs and acyl carnitines have shown that under identical conditions the CMC decreases linearly with increasing acyl chain length (Smith and Powell 1986;Requero et al 1993).…”

“…Determination of critical micellar concentration (CMC) of fatty acyl CoAs of different acyl chain lengths has been the subject of several studies (Constantinides and Steim 1985;Smith and Powell 1986;Das and Hajra 1992;Requero et al 1993). In other studies the membrane perturbing properties of palmitoyl CoA and palmitoylcarnitine were compared by investigating their interaction with phosphatidylcholine (PC) large unilamellar vesicles as well as monolayers (Requero et al 1995a, b).…”

Palmitoylcarnitine, a surface‐active metabolite

“…Requero et al [11] have characterized in detail the binding and solubilization of large unilamellar vesicles of phosphatidylcholine by palmitoylcarnitine; they conclude that this amphiphile has the properties of the commonly used biochemical detergents. The critical micellar concentration of palmitoylcarnitine is in the 10 -5 M range under a variety of conditions, well below the corresponding values for detergents such as Triton X-100 (3.7×10 -4 M), CHAPS (3.5×10 -3 M), or Hecameg (1.65× l0 -2 M) [5]. A low critical micellar concentration is generally indicative of extensive intermolecular hydrophobic interactions.…”

“…lamellar, hexagonal) in the presence of water, a typical property of amphiphiles and surfactants. More recently, Requero et al [5] described the influence of electrolytes and other factors on the critical micellar concentrations and other pertinent properties of acylcarnitines. Finally, Requero et al [6] have provided direct measurements, using a Langmuir-type balance, of the increase in surface pressure that occurs at the air-water interface when palmitoylcarnitine is injected in the bulk of the solvent.…”