Vk x200 3d laser scanning microscope

SRT were extracted from the tentacles of L. vulgaris squid from Tarragona (Spain)^{35 (link)}. SRT protein was dissolved in HFIP to a concentration of 50 mg mL⁻¹, and 1% crystal violet dye was added. 100 μL of solution were cast on polydimethylsiloxane substrates and left to evaporate for at least 3 h, yielding 20 μm protein films. The films were cut in a LPKF ProtoLaser U3 laser cutter (0.189 W, 50 kHz) to the desired motor design (characteristic lengths from 100 μm to 10 mm, Supplementary Fig. 3). Laser micromachining details are described in Supplementary Fig. 2. After machining, an array of motors were mechanically peeled off from the substrate (tweezers and needle tip) and transferred for characterization and analysis. The motors, cut from the same protein film, had homogeneous chemical composition (i.e., equal fuel storage) after the fabrication process (Supplementary Note 3). The motors were imaged in a Leica M205 FA stereomicroscope and in a Keyence VK-X200 3D laser scanning microscope.

Current-time characteristic measurements of MPB SCBK were performed by using a Keithley 4200A semiconductor parametric analyser (Tektronix) and a C-100 probe station from TPSi Company in the dark at room temperature. The SEM image and energy dispersive spectrometry (EDS) mapping results of the gold electrode and MPB SCBK were measured by means of a Phenom Pro-X. A three-dimensional (3D) pseudocolour plot of the gold electrode deposited on the MPB SCBK was obtained by using a KEYENCE VK-X200 3D laser scanning microscope. The absorption spectrum and transmission spectrum were recorded on an Agilent Cary 5000. The XRD measurement was performed by using a BRUKER D8 FOCUS. Raman spectra were recorded on a HORIBA Scientific Raman spectrometer with 785 nm laser excitation in air at room temperature. Steady-state PL spectra of MPB SCBK with different applied voltages were obtained by means of a HORIBA Scientific Raman spectrometer at 473 nm laser with 2.55 m W cm⁻² laser intensity in air at room temperature. The PL confocal micrographs of MPB SCBK were obtained by Nikon ECLIPSE Ti with 486 nm laser excitation in air at room temperature. The J–V characteristic curves of MPB SCBK were obtained by using a Keithley 4200A semiconductor parametric analyser (Tektronix) and a C-100 probe station from TPSi Company in air at room temperature.