This article presents an attempt to develop a transdermal patch based on biodegradable polysaccharides and to investigate its physicochemical properties. Natural polymers, including gellan gum, chitosan, and agar-agar, were chemically cross-linked with glutaraldehyde. Methylene blue was employed as a model drug compound. The resulting polymer-based hydrogel patches for topical application were fabricated in a spherical form, demonstrating both stability and elasticity. The study examined the properties of transdermal patches, their structural components, key characteristics, and evaluation methods essential for their formulation, development, and potential clinical performance. Scanning electron microscopy and UV spectrophotometry were used to characterize the patches. Additionally, the polymer composites were assessed through sol–gel analysis, swelling behavior, and in vitro drug release at pH 4.01 and 9.18.