Skip to main content
. Author manuscript; available in PMC: 2014 Aug 6.
Published in final edited form as: IEEE Trans Ultrason Ferroelectr Freq Control. 2013 Mar;60(3):524–534. doi: 10.1109/TUFFC.2013.2594

Fig. 4.

Fig. 4

Typical force–deformation curves of the poly-L-lysine (PLL)-coated glass surface without microbubble attachment using a cantilever with a spring constant kc = 0.6 N/m. No measurable surface deformation was detected. As the cantilever retracted away from the surface (i.e., unloading), the force-indentation curve showed a small attractive behavior (~0.5 nN), indicating the adhesive nature of the PLL coating.