INS8-0559
Thermoresponsive Chitosan-Based Hydrogel Coatings for Blood-Contacting Medical Devices
Topic
S8. Frontiers of Functional Polymers in Biology and Medicine
When and Where
Sep 29, 2026
16:55 - 17:10
Room 108
Session Chairs
Sung Yun YANG
Kwangsoo SHIN
Presenter(s)
Ik Sung Cho (Kyushu University)
Co-Author(s)
Abstract
Blood-contacting devices such as catheters, extracorporeal circuits, and graft components are prone to thrombosis, biofouling, and infection. Polymer-brush and hydrogel coatings can improve hemocompatibility, but durable coating on PVC remains difficult. Here, we developed hexanoyl-glycol chitosan (HGC), a hydrophobically modified glycol chitosan, as a thermoresponsive coating that is processable at room temperature and gel-locks near body temperature. This enables conformal coating of PVC, including inner lumens, without crosslinkers.
HGC was synthesized by C6 acyl modification of glycol chitosan. Thermogelation was characterized by temperature-ramp rheometry using G′/G″ crossover. PVC plates and tubing were coated by dispensing or dip-coating followed by drying at 50 °C. Stability was evaluated by contact angle and mass changes during PBS immersion. Biointerface performance was assessed by platelet adhesion, erythrocyte morphology, antibacterial assays, and cell viability.
Native glycol chitosan showed no clear sol–gel transition, whereas HGC exhibited thermogelation with G′ exceeding G″ upon heating, indicating temperature-enhanced hydrophobic association. GC coatings gradually lost mass in PBS, while HGC coatings maintained stable coating mass, suggesting improved network integrity and interfacial retention. HGC-coated PVC reduced platelet adhesion compared with uncoated PVC, and this effect was maintained for two months. Whole-blood exposure showed no promotion of echinocytosis on HGC-coated tubing, indicating preserved erythrocyte morphology. HGC-coated samples also suppressed bacterial growth compared with uncoated controls, while dissolved polymers showed no marked cytotoxicity.
Conclusion: HGC offers a simple thermogel-based coating for PVC medical devices, combining room-temperature processability, body-temperature stabilization, long-term durability, hemocompatibility, antibacterial activity, and cytocompatibility.
HGC was synthesized by C6 acyl modification of glycol chitosan. Thermogelation was characterized by temperature-ramp rheometry using G′/G″ crossover. PVC plates and tubing were coated by dispensing or dip-coating followed by drying at 50 °C. Stability was evaluated by contact angle and mass changes during PBS immersion. Biointerface performance was assessed by platelet adhesion, erythrocyte morphology, antibacterial assays, and cell viability.
Native glycol chitosan showed no clear sol–gel transition, whereas HGC exhibited thermogelation with G′ exceeding G″ upon heating, indicating temperature-enhanced hydrophobic association. GC coatings gradually lost mass in PBS, while HGC coatings maintained stable coating mass, suggesting improved network integrity and interfacial retention. HGC-coated PVC reduced platelet adhesion compared with uncoated PVC, and this effect was maintained for two months. Whole-blood exposure showed no promotion of echinocytosis on HGC-coated tubing, indicating preserved erythrocyte morphology. HGC-coated samples also suppressed bacterial growth compared with uncoated controls, while dissolved polymers showed no marked cytotoxicity.
Conclusion: HGC offers a simple thermogel-based coating for PVC medical devices, combining room-temperature processability, body-temperature stabilization, long-term durability, hemocompatibility, antibacterial activity, and cytocompatibility.
