[en] Four different types of nanomaterials will be presented including gold nanoparticles, graphene oxide, MXene (2D nanomaterial) and human serum albumin (HSA, as a biocompatible scaffold) for construction of electrochemical sensors, biosensors and bioanodes of biofuel cells. Gold nanoparticles (AuNPs) were applied for modification of gold electrodes patterned by self-assembled monolayer. Such electrodes were utilised for affinity biosensing using electrochemical impedance spectroscopy (EIS) as a detection platform. AuNPs-modified biosensors (3D configuration) offered much lower limit of detection compared to the biosensor configuration without using AuNPs (2D configuration). Graphene oxide (GO) was successfully applied for modification of electrodes for construction of affinitybased biosensors and for preparation of a bioanode. EIS-based affinity biosensors with immobilised lectins (carbohydrate binding proteins) were successfully utilised for detection of glycoproteins down to aM level (10^-18 M). Protocol of immobilisation of bilirubin oxidase (BOD) on GO affected current density for oxygen reduction significantly from 2.6 μA cm^-2 to 280 μA cm^-2. GO flakes with a tuned density of a negative charge significantly influenced density and orientation of BOD immobilised by a passive physisorption with the highest current density of 597 μA cm^-2. Besides GO we applied in our studies another 2D nanomaterial - Mxene. Using this nanomaterial we were able to detect H₂O₂ down to 0.7 nM with one of the highest sensitivity of H₂O₂ detection observed so far i.e. 596 mA cm^-2 mM-1. The last type of nanomaterial HSA was applied in our studies as a scaffold for immobilisation of small glycan antigen. The glycan biosensor was then applied for detection of an antibody, what is an approach applicable for analysis of glycan autoantibodies, which are considered as biomarkers of various types of cancer. (authors)