1 research outputs found
Cavity Orientation Regulated by Mixture Composition and Clustering of Amphiphilic Cyclodextrins in Phospholipid Monolayers
Artificial
supramolecular-hierarchical structures that emulate
nature represent an overcoming alternative for the design of new drug
delivery systems. Thermodynamic and topographic properties of films
formed by a monoacylated amphiphilic β-cyclodextrin (βCD-C16)
with the phospholipid 1-palmitoyl-2-oleoyl-<i>sn</i>-glycero-3-phosphocholine
(POPC) at the air/water interface were studied. βCD-C16 formed
stable mixed films with POPC at several proportions when spread together
at the air/water interface. The orientation of βCD-C16 cavity
at the interface depends on its mole fraction in the film as reveled
by the analysis of partial mean molecular areas as a function of composition.
Furthermore, βCD-C16 was able to penetrate POPC preformed films
in a broad range of initial surface pressures, including that near
the collapse pressure of the phospholipid. These results demonstrated
the strong tendency of βCD-C16 to be inserted into this lipid
matrix commonly used in liposome formulations. Topography studies
show that βCD-C16 segregate from POPC forming clusters enriched
in βCD-C16. Segregation of βCD-C16 was especially noticeable
when βCD-C16 were incorporated by themselves into a preformed
POPC matrix leading to ordered and highly birefringent structures
that suggest the formation of hierarchical stacked βCD-C16 arrangement
at the interface