Table 2.

Characterization techniques of electrochemical glycobiosensors.

Characterization Technique	Properties	Technique Principle	References
AFM	Morphology	Measurement of intermolecular forces and “seeing” atoms by using probe surfaces.	[70]
SEM/EDX	Morphology Composition	Application of kinetic energy to produce signals from the interaction of the electrons (secondary, backscattered, and diffracted backscattered). Secondary and backscattered electrons are used to visualize the morphology, and backscattered are related to composition.	[71,72]
FT-IR	Surface chemical composition	Measurement of the vibrations of atoms, and from this, functional groups are determined.	[73]
XPS	Surface chemical composition	The sample is irradiated with an X-ray, and some electrons become excited enough to escape from the atoms. The photo-ejected electrons are collected by an electron analyzer that measures their kinetic energy, allowing the element to be identified.	[73]
TGA, DSC	Sorption Composition	The sample is heated or cooled under controlled conditions and changes in some physical properties are measured.	[74,75]
UV-vis, PL	Optical	Light absorption and scattering by a sample.	[76]
CV, DPV, EIS, ECS	Electron transfer kinetics	Perturbation of the electrode by applying an electric potential and recording the resulting current.	[77,78]
Biacore	Bioreceptors affinity	The change in SPR response is measured after association/dissociation of a bioreceptor and ligand, respectively, with the sample flow in a microfluidic channel.	[80]

Abbreviations: AFM: atomic force microscopy. CV: cyclic voltammetry. DPV: differential pulse voltammetry. DSC: differential scanning calorimetry. ECS: electrochemical capacitance spectroscopy. EIS: electrochemical impedance spectroscopy. EDX: energy-dispersive X-ray spectroscopy. FT-IR: Fourier transform infrared spectroscopy. PL: photoluminescence. SEM: scanning electron microscopy. TGA: thermogravimetric analysis. UV-vis: ultraviolet-visible spectroscopy. XPS: X-ray photoelectron spectroscopy.