INVESTIGADORES
PALMA Santiago Daniel
artículos
Título:
Evaluation of surfactant properties of ascorbyl palmitate sodium salt
Autor/es:
SANTIAGO DANIEL PALMA; LO NOSTRO, PIERANDREA; HILARIO MANZO, RUBEN; ALBERTO ALLEMANDI, DANIEL
Revista:
European Journal of Pharmaceutical Sciences
Referencias:
Año: 2002 vol. 16 p. 37 - 43
ISSN:
0928-0987
Resumen:
In this paper we report on the physicochemical surface properties of ascorbyl palmitate (Asc16) and of its sodium salt (Asc16Na) with a
view to their use as surfactants. Asc16Na was synthesized from ascorbyl palmitate by neutralizing the OH groups in position 3 of the
ascorbyl ring. The acidbase properties, thermal analysis and stability of Asc16Na monomers were determined. Self-assembling
parameters of micellar aggregates in aqueous dispersions through critical micellar concentration (CMC) and critical micellar temperature
(CMT) were measured. Asc16Na micellar dispersions efficiently solubilize poorly soluble drugs such as phenacetin and griseofulvin, and
enhance their apparent solubility in aqueous environments.. Stability tests showed that Asc16Na is more unstable than ascorbyl palmitate.
Ascorbyl palmitate and its sodium salt are insoluble at room temperature in water, but their solubilities strongly depend on temperature,
and largely increase above the CMT. Although Asc16Na is insoluble at room temperature, it is more soluble than Asc16, and its CMT
significantly lowers in the undissociated acidic form. The apparent solubilities of phenacetin and griseofulvin are increased in Asc16Na
aqueous solutions. The Asc16Na potential use as surfactant is restricted by its low stability in water, therefore the addition of some
antioxidant species is necessary