Strategies toward Renewable and Compostable Intravenous Bag Materials

The medical industry contributes significantly to single-use plastic waste, as illustrated most recently by the COVID-19 pandemic. While safety standards mandate the use of disposable, single-use items for the highest-value applications, there is an opportunity to pursue greater circularity in higher-volume, bulk plastic goods, including intravenous (IV) bags. Herein, we assessed two thermoplastic elastomers based on renewable, compostable poly(γ-methyl-ε-caprolactone) (PγMCL) as IV bag material alternatives to the nonrenewable, potentially harmful phthalate-plasticized poly(vinyl chloride) (PVC) industry standard. We synthesized a thermoplastic poly(urethane-urea) (TPUU) and 4-arm PγMCL-b-poly((-)-lactide) star-block polymer ((ML)₄) on >55 g scales and comprehensively evaluated their mechanical and (bio)chemical readiness for an IV bag application. The TPUU showed excellent mechanical parity with PVC, and both PγMCL-based materials displayed superior cytocompatibility to PVC. An in vivo implantation study in a rat model revealed no significantly adverse histopathology resulting from direct tissue contact with the TPUU or (ML)₄. The PγMCL-based materials also conform to ISO-standardized chemical hazard thresholds similarly to PVC. Our work is the first to target IV bag waste through direct replacement of current materials with intrinsically circular polymers, providing an evaluation framework for future IV bag candidates and expanding PγMCL's application scope to the biomedical sector.