Other characterization techniques are used to confirm the incorporation of nano-objects in the hydrogel matrix and the establishment of interactions among components. They include Fourier transform infrared spectroscopy (FTIR), thermal analysis, Raman spectroscopy, X-ray diffraction, , photoelectron spectrometry atomic force microscopy (AFM) or electrochemical impedance spectroscopy (EIS). Among them, the choice of an appropriate technique to characterize hybrid hydrogels is often governed by the inherent properties of the material (e.g., EIS for hydrogels containing conductive nano-objects), but also guided by specific analytic objectives and the impact of the results on subsequent stages of the investigation.