Buffers can modulate the effect of sonication on egg lecithin liposomes.
When model membranes are prepared by ultrasonic irradiation of polyunsaturated phospholipids, radical production can induce a partial degradation of the polyunsaturated fatty acyl chains and the formation of lipid hydroperoxides. A suitable buffer employed during liposome preparation, like Hepes or Tris, is able to exhibit a protective effect against lipid peroxidation. Hepes has been found to be the most effective: a 10 mM concentration provides a 70% protection after 30 min sonication. Tris, in the same conditions, exhibits a 50% protection. These findings may be explained on the basis of the rate constants of these organic buffers with hydroxyl radicals.
Fiorentini
D
D
Dipartimento di Biochimica, Universitá di Bologna, Italy.
Landi
L
L
Barzanti
V
V
Cabrini
L
L
D002021:Buffers; D004531:Eggs; D005609:Free Radicals; D015227:Lipid Peroxidation; D008081:Liposomes; D010084:Oxidation-Reduction; D010713:Phosphatidylcholines; D013010:Sonication; D014465:Ultrasonics
D002021:Buffers; D005609:Free Radicals; D008081:Liposomes; D010713:Phosphatidylcholines