Fig. 3

Penetration test of STAMP. A Schematic diagram of mechanical strength test of STAMP. The tips could be separated when the applied force is above 0.1 N (purple arrow). B Photography of STAMP, loaded with Trypan blue dye, inserted into the porcine skin. Typical microchannels could be investigated obviously under the microscope. Left scale bar, 2 mm; Right scale bar, 1 mm. C Pathological section of BALB/c mouse skin after microneedle insertion at different time points. Scale bar, 50 μm. D Photograph of BALB/c mouse skin during treatment. Scale bar, 1 mm. E Photograph of BALB/c mouse skin right after the treatment (left) and the recovered skin (right). Scale bar, 1 mm. F Fluorescence image of the FITC marked egg and the unmarked egg. G The bright-field, fluorescence and merged images of Schistosoma japonicum egg labeled by FITC, Scale bar, 200 μm. H The fluorescence image of porcine skin imprinted by STAMP, Scale bar, 1 mm. I The two sections below showed egg structures (the egg shell outside and the miracidium inside) at the skin incision, Scale bar, 50 μm