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The industrially used flame synthesis of silica polymer fillers was extended to amorphoustricalcium phosphate (a-TCP) nanoparticles and resulted in a similar morphology as thetraditionally used polymer fillers. Doping of poly(lactide-co-glycolide) (PLGA) with suchhighly agglomerated a-TCP was investigated for mechanical properties, increased in vitrobiodegradation and the formation of a hydroxyapatite layer on the surface ofthe nanocomposite. PLGA films with particle loadings ranging from 0 to 30wt%were prepared by solvent casting. Degradation in simulated body fluid (SBF) at37 C under sterile conditions for up to 42 days was followed by Raman spectroscopy, scanningelectron microscopy (SEM), thermal analysis and tensile tests. The presence ofnanoparticles in the PLGA matrix slightly increased the Young’s modulus up to 30%compared to pure polymer reference materials. The nanoparticle doped films showed asignificantly increased loss of polymer mass during degradation. Scanning electronmicroscopy images of doped films showed that the SBF degraded the PLGA by corrosion asfacilitated by the incorporation of nanoparticulate calcium phosphate. Ramanspectroscopy revealed that the deposition of about 10nm sized hydroxyapatitecrystallites on the surface of doped PLGA films was strongly increased by theaddition of tricalcium phosphate fillers. The combination of increased hydroxyapatiteformation and enhanced polymer degradation may suggest the use of such amorphous,aerosol derived a-TCP fillers for applications in non-load-bearing implant sites. [ABSTRACT FROM AUTHOR]