Polyurethanes are widely used in the development of medical devices due to their biocompatibility, degradability, non-toxicity and chemical versatility. Polyurethanes were obtained from polyols derived from castor oil, and isophorone diisocyanate, with the incorporation of polycaprolactone-diol (15% w/w) and chitosan (3% w/w). The objective of this research was to evaluate the effect of the type of polyol and the incorporation of polycaprolactone-diol and chitosan on the mechanical and biological properties of the polyurethanes to identify the optimal ones for applications such as wound dressings or tissue engineering. Polyurethanes were characterized by stress-strain, contact angle by sessile drop method, thermogravimetric analysis, differential scanning calorimetry, water uptake and in vitro degradation by enzymatic processes. In vitro biological properties were evaluated by a 24 h cytotoxicity test using the colorimetric assay MTT and the LIVE/DEAD kit with cell line L-929 (mouse embryonic fibroblasts). In vitro evaluation of the possible inflammatory effect of polyurethane-based materials was evaluated by means of the expression of anti-inflammatory and proinflammatory cytokines expressed in a cellular model such as THP-1 cells by means of the MILLIPLEX^® MAP kit. The modification of polyols derived from castor oil increases the mechanical properties of interest for a wide range of applications. The polyurethanes evaluated did not generate a cytotoxic effect on the evaluated cell line. The assessed polyurethanes are suggested as possible candidate biomaterials for wound dressings due to their improved mechanical properties and biocompatibility.

Objectives: GI endoscopy units represent the third largest producers of medical waste. We aimed to determine endoscopic instrument composition and life cycle assessment (LCA) and to assess a sustainability proposal based on a mark on the instruments that identifies parts can be safely recycled or ‘ green mark ’. Design: Material composition analysis and LCA of forceps, snares and clips from four different manufacturers (A–D) were performed with four different methods. Carbon footprint from production, transportation and end of life of these instruments was calculated. In 30 consecutive procedures, we marked the contact point with the working channel. 5 cm away from that point was considered as green mark . One-week prospective study was conducted with 184 procedures evaluating 143 instruments (75 forceps, 49 snares and 19 haemoclips) to assess the efficacy of this recyclable mark. Results: Composition from different manufacturers varied widely. Most common materials were high global warming potential (GWP) waste (polyethylene, polypropylene and acrylonitrile) and low GWP waste (stainless steel). Significant differences were found for the forceps (0.31–0.47 kg of CO ₂ equivalent (CO ₂ -eq)) and haemoclips (0.41–0.57 kg CO ₂ -eq) between the manufacturers. Green mark was established 131.26 cm for gastroscope and 195.32 cm for colonoscope. One-week activity produced 67.74 kg CO ₂ -eq. Applying our sustainability intervention, we could reduce up to 27.44% (18.26 kg CO ₂ -eq). This allows the recycling of 61.7% of the instrument total weight (4.69 kg). Conclusion: Knowledge of carbon footprint is crucial to select the most sustainable alternatives because there are large variations between brands. A mark to identify recyclable parts could reduce our environmental impact significantly.