Poly(glycerol adipate) (PGA) is a biodegradable poly
mer with pro
mising features for nanoparticulate drug carrier syste
ms. By acylation of PGA with fatty acids, co
mposite syste
ms with a
mphiphilic properties can be obtained. Variation of the fatty acid (laurate, stearate and behenate) and their substitution degrees lead to a wide range of different poly
mer structures. This strongly influences the aggregation of the poly
mer and thus the nature of the resulting colloidal syste
m. Based on the
modification of the interfacial deposition
method, various self-stabilizing nanoparticles with defined sizes and narrow size distributions could be prepared. Non-spherical shapes (squares, pentagons) with an internal la
mellar-like structure were observed for low substituted PGA-stearates. Higher substitution degrees lead to ellipsoidal or spherical particles.
The size, charge, fluidity and polarity of the nanoparticles have been studied comprehensively by PCS, AF4, zeta potential measurements, DSC, NMR, TEM and fluorescence spectroscopy. The chain lengths of the attached fatty acids as well as their substitution degree substantially influence the physicochemical properties of the bulk polymers and the nanoparticles. With their diverse particle shapes and internal structures as well as their different thermal behavior, aggregate states and polarities, the systems offer promising possibilities as delivery systems for lipophilic, amphiphilic and water soluble drugs.