Fig. 2: Characterization of the PTM.

a Schematic diagram showing the mechanism of LLCP layer deformation upon irradiation with 470 nm light. b Photographs showing local radial expansion of the PTM cross section before and after irradiation with 470 nm light (80 mW cm⁻²). When the light is switched on, the PTM generates local expansion radially. As a consequence, the exposed surface of the PTM displaces upward 36.9 μm. After continuous illumination for 0.5 s, the displacement of the exposed surface reaches the maximum value. When the light is switched off, the displacement recovers within 0.5 s. The rapid recovery of the PTM is mainly due to the entropic restoring force of exposed regions and the elastic recovery of unexposed regions. Scale bar: 100 μm. c Photographs showing the photocontrolled motion of a protein droplet in the PTM. The intensity of the 470 nm light is 80 mW cm⁻². Scale bar: 2 mm. d Velocities of various reagent solution droplets, including phosphate buffered saline (PBS), protein solution, fluorescence solution, and magnetic nanoparticle (MNP) suspension, used during protein analysis in the PTM. e Schematic representation of the force analysis during the photocontrolled motion of droplets in the PTM, where F_d is the driving force, F_r is the resistance force, F_a is the adhesion force, and CA is the contact angle. f CAs of a 3 μL PBS droplet on the inner wall of the PTM before (top) and after (bottom) BSA modification. g Adhesion force curves of a 3 μL PBS droplet on the inner wall of the PTM before and after BSA modification. The maximum force decreases from 0.339 ± 0.031 mN (black) to 0.259 ± 0.043 mN (blue).