Disposable stochastic sensors obtained by nanolayer deposition of copper, graphene, and copper-graphene composite on silk for the determination of isocitrate dehydrogenases 1 and 2

Three disposable stochastic sensors designed using nanolayer deposition of copper (Cu), graphene (GR), and copper-graphene (Cu-GR) composite on the silk textile, as substrate, were modified with chitosan ( n =371–744), for biomedical analysis. Isocitrate dehydrogenase 1 (IDH1) and isocitrate dehydrogenase 2 (IDH2) served as model analytes for molecular recognition and quantification in biological samples such as whole blood and brain tumor tissue samples. The best sensitivities (3.77×10 7 s μg mL −1 for IDH1, and 1.88×10 7 s μg mL −1 for IDH2) and the lowest limits of quantification (10 −2 fg mL −1 for IDH1, and 5×10 −2 fg mL −1 for IDH2) for both IDH1 and IDH2 were recorded for the disposable stochastic sensors based on chitosan/graphene nanolayer. Very good correlations between the screening method based on disposable stochastic sensors and enzyme-linked immunosorbent assay (ELISA) were obtained; this was also proved by the results obtained using the paired t -test. Graphical abstract