{
    "protocol": "1. Formulation: Dissolve monomer (acrylamide, AAm) and coupling agent (3-(trimethoxysilyl)propyl methacrylate, TMSPMA) in water to create an aqueous solution. Include other compounds as necessary (initiators, chain transfer agents, rheological modifiers, etc.). 2. Polymerization: The monomer and the coupling agent copolymerize into uncrosslinked p(AAm-co-TMSPMA) chains via free-radical polymerization. 3. Substrate preparation: Impart hydroxyl groups onto the surface of the substrate to ensure complementary functional groups to the silanols. 4. Application: Apply the uncrosslinked polymer chain solution onto the prepared substrate using methods such as brush, cast, dip, spin, or spray. 5. Cure: Allow the paint to cure by enabling the silanol groups to condense and crosslink the polymer chains into a polymer network, while simultaneously bonding the polymer network to the substrate through the formation of siloxane bonds.For 1 mL solution of AAm (2 moles per a liter of DI water, 2 mol L^{-1} ), 1 μL of CTA (10% volume ratio in THF), 10 μL of acetic acid (0.1 moles per a liter of DI water, 0.1 mol L^{-1} ), and 5.7 μL of TMSPMA are added, followed by vortex mixing for 60 s. Then, 2 μL of I-2959 (0.1 moles per a liter of ethanol, 0.1 mol L^{-1} ) is added followed by vortex mixing for 10 s. The resulting transparent solution is drawn into a plastic syringe and subjected to UV irradiation (15W 365 nm; UVP XX-15L, 5 cm distance between sample and bulb). After 30 min, the p(AAm-co-TMSPMA) hydrogel paint is obtained. Nitinol guidewire is washed with IPA, acetone, and DI water in sequence twice and then dried by air. The guidewire is immersed in the p(AAm-co-TMSPMA) hydrogel paint and pulled out vertically with a constant velocity of 10 mm min^{-1}. The coated wire is sealed in a bottle with saturated humidity and stored in an oven at 65°C for 24 h."
}