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Imaging techniques based on mass spectrometry or spectroscopy methods inform in situ about the chemical composition of biological tissues or organisms, but they are sometimes limited by their specificity, sensitivity, or spatial resolution. Multimodal imaging addresses these limitations by combining several imaging modalities; however, measuring the same sample with the same preparation using multiple imaging techniques is still uncommon due to the incompatibility between substrates, sample preparation protocols, and data formats. We present a multimodal imaging approach that employs a gold-coated nanostructured silicon substrate to couple surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) and surface-enhanced Raman spectroscopy (SERS). Our approach integrates both imaging modalities by using the same substrate, sample preparation, and data analysis software on the same sample, allowing the coregistration of both images. We transferred molecules from clean fingertips and fingertips covered with plasticine modeling clay onto our nanostructure and analyzed their chemical composition and distribution by SALDI-MS and SERS. Multimodal analysis located the traces of plasticine on fingermarks and provided chemical information on the composition of the clay. Our multimodal approach effectively combines the advantages of mass spectrometry and vibrational spectroscopy with the signal enhancing abilities of our nanostructured substrate.

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In this work, electro-responsive shape-memory actuators were developed by incorporating a conductive heater in a dual-curing thiol-acrylate-epoxy shape-memory polymer (SMP). A conductive heater, consisting of an electrically conductive silverink track printed on Kapton ® substrate, was assembled to the SMP, taking advantage of the dual-curing processing. The shape-memory effect (SME) was activated by the heat dissipated by the Joule effect in the conductive track. Boron nitride agglomerates were dispersed in the thiol-acrylate-epoxy layers to increase thermal conductivity and achieve faster shape-recovery. A thermoelectric control unit was developed to control the shape recovery of the electro-responsive actuators and provide different activation strategies. The electrically activated SME was investigated and compared to a traditional SME based on an external heating source given by the dynamic mechanical analyzer (DMA) apparatus. Electro-responsive actuators were found extremely faster than the conventional SMPs based on external heating. The fastest recovery was obtained by the 15% boron nitride actuator, which recovered the 100% of the original shape in only 8 s. The thermoelectric controlling device provided an optimal control of the shape recovery speed based on the pulse width modulation of the heating current under the application of a low voltage (5 V).