Tailoring vancomycin release from β-TCP/agarose scaffolds

In this work a multifaceted approach to the fabrication of scaffolds is considered, that is, besides the preparation technique, the introduction of substances that may contribute to enhance their final performance, as well as the techniques required to ensure the correct preservation of the so obtained scaffolds are taken into account to tailor the release of vancomycin from β-tricalcium phosphate (β-TCP)/agarose scaffolds. These materials were prepared by a shaping technique that allows to obtain pieces at a temperature low enough to simultaneously include active substances susceptible of heat degrading such as vancomycin, the model drug considered in this work. In the first approximation poly(ethylene glycol) (PEG), a hydrophilic substance employed as a matrix capable of binding compounds such as proteins or peptides and release them in a controlled fashion, was included in the formulation. The second tool to govern the vancomycin liberation is based on the drying procedures employed to process and preserve the obtained scaffolds: freeze-drying and heat desiccation at 37 °C. These modifications resulted in the generation of different pore architectures and certain chemical interactions, such as the formation of an agarose–PEG–vancomycin complex that yielded different drug release patterns. The so obtained pieces behave like a hydrogel when immersed in a hydrated medium but show a consistency comparable to that of the cancellous bone.