Fig. 1: Overview of wf-UMP.

a Schematic illustration of wf-UMP application for cancer therapy. Created by figdraw.com. b Schematic of the integrated system-level wf-UMP electronics, consisting of a flexible US transducer array for effective US emission, a bioadhesive hydrogel elastomer for robust adhesion and acoustic coupling layer, and a mKNN PNPs-loaded MN patch for drug delivery. c, d Schematic illustration of the operational procedure of wf-UMP for tumor immunotherapy. Step 1: Insertion and dissolution of MNs (b). Step 2: Diffusion of mKNN PNPs and ROS generation under US stimulation, along with activation of systemic immune responses (c). e SEM image of mKNN MN. Scale bar, 100 μm. f TEM image of mKNN PNPs. Scale bar, 50 nm. g Schematic illustration of the generation of ROS by mKNN PNPs under US stimulation. h Schematic illustration of the robust adhesion of the bioadhesive hydrogel via amide bond formation at the interface. i, j Mechanical properties of the US transducer array under tensile stress, demonstrated by experimentally stretching the transducer array (i) and corresponding FEA simulated strains (j). Scale bar, 2.5 mm. k Photograph of the US transducer array adhering to curved surfaces, showing its mechanical flexibility. Scale bar, 4 mm. l Photograph of wf-UMP adhered seamlessly on skin. Scale bar, 5 mm. m Photograph demonstrating the robust adhesion of wf-UMP with skin. Scale bar, 5 mm. n H&E staining of mouse skin after the insertion of MNs. Scale bar, 100 μm.