Microparticle drug carriers made of biodegradable functional polyesters were produced. The polyesters consist of a poly(ε‐caprolactone) backbone bearing pendant acryloyloxy and methacryloyloxy groups. Stable microparticles were prepared via an oil/water emulsion‐solvent evaporation technique eventually combined with a simultaneous crosslinking procedure. Crosslinked particles were obtained via photo‐crosslinking and Michael type addition using diamines as crosslinking agents. Encapsulation of a hydrophobic fluorescent dye and a hydrophilic protein, as model drugs, were performed and confirmed by optical microscopy and Raman spectroscopy. The presence of the functional groups allow for not only the tuning of the degradation rate, but also for further processing and (bio)functionalization.
Heterobifunctional poly(ethylene glycol)s can be used for many biomedical applications ranging from solubility enhancement of hardly soluble compounds to surface modification of medical devices. In order to modify gold nanoparticles as model particles for drug targeting applications, PEG derivatives are synthesized that possess a high affinity for gold surfaces, namely a thioalkyl function, known to form stable monolayers on gold. Additionally a bisphosphonate function is introduced in the PEG molecule to allow targeting of hydroxyapatite rich tissues, like bone. Gold nanoparticles are modified using the synthesized bifunctional PEG and investigated for their stability in biological fluids and their ability to bind to hydroxyapatite granules in these fluids.
