Construction of a Novel Poly(vinyl alcohol) Drug-Loaded Microcatheter via an Acrylamide/Sodium Alginate Hydrogel Coating Initiated by UV Light

To enhance the application potential and added value of an independently developed self-lubricating poly(vinyl alcohol) (PVA) interventional microcatheter, a novel strategy for in situ formation of acrylamide/sodium alginate (AM/SA) hydrogel coating on the surface of the PVA microcatheter via UV light initiation was proposed. And the comprehensive effects of key parameters including composition, light intensity, irradiation time, and photoinitiator concentration on drug loading, release profile, adhesion, and lubricity of the coating were systematically studied. By adjusting the UV light intensity (20–50%), exposure time (3–20 min), and initiator concentration (0.125–1%), the thickness of the hydrogel coating could be controlled in the range of 13.4 to 791 μm, significantly improving the drug loading and release capacity of the microcatheter, from 283.45 μg/g of pure PVA to 2070.11 μg/g, and the cumulative release within 24 h could reach 80.13%. The hydrogel coating also exhibited excellent interface stability, achieving high adhesion energy of 201 J/m 2 at the photoinitiator concentration of 0.5%. With moderate SA content, e.g., 5%, the surface friction coefficient of the catheter was significantly reduced to 0.04, representing a reduction of ∼21% compared to pure PAM coating and also better than that of pure PVA (0.0596). This AM/SA hydrogel coating integrated the triple functionality of drug loading, controlled drug release, and surface lubrication, markedly enhanced the multifunctional integration and application value of PVA catheter, and would provide a new strategy for developing high-performance interventional medical devices used in the field of short-term nonvascular luminal interventional procedures.