Starch-Based scaffold produced by FDM 3D printing technique as Innovative and biosustainable wound dressing

Starch is a safe biopolymer, whose use for the production of scaffolds intended for deep wounds treatment is limited, due to its low mechanical and thermal properties. For this reason, until now, it has been used in low amounts and/or in combination with other biopolymers. The aim of the study was to produce thermoplastic filaments (TPS) with high starch content, useful for scaffolds production by Fusion Deposition Modelling 3D printing technique. TPS was obtained by hot melt extrusion from a mixture of starch (70 % w/w) and glycerol (30 % w/w) combined to cationic clay montmorillonite, citric acid and magnesium stearate to improve strength and processability. The prepared scaffold was characterized and compared to other two scaffolds, where the effect of the addition of polycaprolactone (PCL) or methylsulphonylmethane (MSM) (as thermostable model drug) to the blend was evaluated. The mechanical properties were investigated by Brillouin Light Scattering. In vitro studies highlighted that the scaffolds are: i) able to absorb simulated exudates (reaching a hydration of 35 % in 7 days); ii) safe on keratinocytes (viability > 70 %) stimulating their growth; iii) able to inhibit S. pyogenes growth.