▎ 摘　　要

NOVELTY - Hydrogel patch comprises a hydrogel comprising a polymer, and nanoparticles dispersed in the hydrogel, where the hydrogel and nanoparticles have different charges. USE - The hydrogel patch is useful for improving skin disease e.g. atopic dermatitis by providing a wet environment where the skin disease occurs, and removing active oxygen species, which are the main cause of oxidative stress in the body and suppressing chronic inflammation to restore the damaged skin barrier and thickened epidermal layer. The hydrogel patch is also useful as a drug delivery system for treating skin disease. ADVANTAGE - The hydrogel patch has high biocompatibility. The nanoparticles do not remain on the skin when the patch is removed, as the hydrogel and the nanoparticles are strongly bonded due to their different charges. The patch is soft and flexible, hence can be easily attached to and detached from joints and protruding areas, and the patient's convenience can be increased when the patch is attached for a long time. The patch can be produced as large-area patches based on the condition and size of the skin disease area by adjusting the capacity of nanoparticles and the thickness of the hydrogel. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing hydrogel patch, which involves (a) preparing a first solution comprising nanoparticles, (b) preparing a second solution comprising a crosslinking agent and the polymer, and preparing a mixed solution by adding the first solution and the crosslinking accelerator to the second solution.