Hydrophobic Effects in the Critical Destabilization and Release Dynamics of Degradable Multilayer Films.

Recent research has highlighted the ability of hydrolytically degradable electrostatic layer-by-layer films to act as versatile drug delivery systems capable of multi-agent release. A key element of these films is the potential to gain precise control of release by evoking a surface-erosion mechanism. Here we sought to determine the extent to which manipulation of chemical structure could be used to control release from hydrolytically degradable layer-by-layer films through modification of the degradable polycation.

MAD (multiagent delivery) nanolayer: delivering multiple therapeutics from hierarchically assembled surface coatings.

We present hydrolytically degradable polymeric multilayer films that can codeliver multiple therapeutics of differing chemical characteristics (charged biomacromolecules and neutral hydrophobic small molecules) from a surface. This multiagent-delivery (MAD) nanolayer system integrates the hydrolytically degradable poly(beta-amino ester) as a structural component to control the degradation of the multilayers to release active therapeutic macromolecules as well as hydrophobic drugs imbedded within amphiphilic block copolymer micellar carriers within layer-by-layer (LbL) films, which would otherwise be difficult to include within the multilayers. By varying the anionic therapeutic agents (heparin and dextran sulfate) within the multilayer, we examine how different structural components can be used to control the release kinetics of multiple therapeutics from MAD nanolayers.

Polyelectrolyte multilayers for tunable release of antibiotics.

Polyelectrolyte multilayers incorporating gentamicin were fabricated using layer-by-layer deposition. The multilayers could be precisely tuned with regard to dosage, and release rate under aqueous physiological conditions could be controlled. The films were demonstrated efficacious against Staphylococcus aureus and nontoxic toward murine osteoblasts MC3T3.