Formulation of liposomal preparations containing arginine-based surfactants

FAIT, M.E.; HERMET, M.; CAIMI, A.; PÉREZ, A.P.; ROMERO, E.L.; MORCELLE, S.R.; BAKÁS, L.

Buenos Aires

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Biofísica; 2018

SAB

Two novel arginine-based cationic surfactants, Nα-benzoyl-arginine decylamide(Bz-Arg-NHC10) and Nα-benzoyl-arginine dodecyl amide (Bz-Arg-NHC12), weresynthesized using papain (an endopeptidase from Carica papaya latex) adsorbedonto polyamide as biocatalyst. Nα-benzoyl-arginine ethyl ester hydrochloride (theclassical substrate for the determination of cysteine and serine proteases activity)was used as arginine donor, whereas decyl- and dodecylamine were used asnucleophiles for the condensation reaction, with yields higher than 80%. Thepurification process was achieved by a single cationic exchange chromatographicseparation, involving the use of water and ethanol as the main separationsolvents. Liposomal formulations made of soy phosphatidylcholine (SPC) asphospholipids (10 mg.mL-1) and Bz-Arg-NHCn (n=10 or 12; 20-40% mol.mol-1) asedge activators were prepared by the thin-film hydration method. The liposomalsuspensions were sonicated (60 min with a bath-type sonicator, 80 W, 40 KHz) andextruded 10 times through two stacked 0.2 μm and 0.1 μm pore polycarbonatefilters using a 100 ml Thermobarrel extruder. Size (liposomal diameter) and zetapotential were determined by dynamic light scattering and phase-analysis lightscattering, respectively. The deformability values (D) of the liposomes were alsocalculated and phospholipids were quantified by a colorimetric phosphatemicroassay. For storage stability characterization, mean size, polydispersity and Zpotential were measured upon storage during 3 weeks at 4°C in darkness. Basedon these results, both arginine-based surfactants could be used as additives intopical formulations exerting their activity on the skin surface.