Injectable, retrievable nanocellulose-polymer composite cryogel microfibers for resolving the dual clinical challenge of residual silicone oil and emulsification in eye surgery.

While nanocellulose-containing materials show remarkable oil-absorption capabilities for oil-spill cleanup, their biomedical translation remains unexplored. Residual silicone oil (SilOil) following eye surgery represents a significant concern in clinical ophthalmology, as emulsified droplets can lead to serious ophthalmic complications. Here, we demonstrate the first successful biomedical application of a carbohydrate-polymer composite material as an intraoperative SilOil-absorbent tool with a clinically viable form in eye surgery. The engineered microfibers (MFs) were fabricated via wet-reaction spinning of TEMPO-oxidized cellulose nanofibrils (TOCN) and polyvinyl alcohol (PVA), followed by dual crosslinking, freeze-drying, and hydrophobic modification. The resulting composite cryogel MFs exhibited high porosity (up to 86%), exceptional SilOil absorption capacity (more than 12 g per gram (g g-1)), mechanical robustness (70 MPa compressive modulus), and excellent cytocompatibility. The precisely controlled cylindrical morphology enables seamless integration with microcannula systems, permitting both minimally invasive delivery and complete retrieval. Crucially, the composite cryogel MFs achieved superior SilOil removal efficiency compared to the conventional technique in an ex vivo porcine eye model. This work pioneers the transformative application of a structured carbohydrate-polymer composite cryogel as a retrievable intraoperative surgical tool for the management of post-surgery SilOil retention and advances the utilization of carbohydrate-polymer composite porous materials in precision surgery.