The SPR sensorgrams (Figure ) show the interactions of the target peptide FTVRDLS at five different concentrations with the Hf-BTB-NH2 nanosheets (Figure ). To study cross-reactivity and non-specific binding to the nanosheets were also investigated with non-target peptides YNYRNLL (Figure ) and NNWWAPA (Figure ) were also examined, Tween 20 surfactant (0.01%) was added to the running buffer to minimize non-specific binding. Experiments were repeated in triplicate and the SPR curves were fitted to a 1:1 interaction model.