Figure 7.

(A) Changes in the resonance frequency (Δf) and motional resistance (ΔR_m) of the quartz crystal microbalance (QCM) transducer modified by a 1-mM peptide substrate and mercaptohexanol after the addition of 20-nM plasmin. (B) Plots of relative changes of the Δf and ΔR_m, a function of plasmin concentration (Δf = f − f₀ and ΔR_m = R_m − R₀); here, f₀ and R₀ are the frequency and resistance measured before the addition of plasmin, respectively. The results represent the mean ± S.D. obtained from 3 independent measurements performed for each concentration of plasmin. Reproduced with permission of Elsevier from Poturnayova et al. [63].