Real-time QCM-D monitoring of cellular responses to different cytomorphic agents

Abstract

Quartz crystal microbalance with dissipation monitoring (QCM-D) is used for real-time in situ detection of cytoskeletal changes in live primary endothelial cells in response to different cytomorphic agents; namely, the surfactant Triton-X 100 (TX-100) and bacterial lipopolysaccharide (LPS). Reproducible dissipation versus frequency (Df) plots provide unique signatures of the interactions between endothelial cells and cytomorphic agents. While the QCM-D response for TX-100 can be described in two steps (changes in the osmotic pressure of the medium prior to observing the expected cell lysis), LPS results in a different single-phase signal. A complementary analysis is carried out to evaluate the possible competitive effects of TX-100 and LPS through the QCM-D response to BAEC stress by analyzing the Df plots obtained. Experiments with non-toxic components (fibronectin or serum) produce a different QCM-D response than that observed for the toxic chemicals, suggesting the use of Df plot signatures for the possible differentiation between cytotoxic or non-cytotoxic effects. Observations obtained by QCM-D signals are confirmed by conducting fluorescence microscopy at the same time. Our results show that a fast (few minutes) sensing response can be obtained in situ and in real-time. The conclusions from this study suggest that QCM-D can potentially be used in biodetection for applications in drug screening tests and diagnosis.

Cooperative Binding of Annexin A2 to Cholesterol- and Phosphatidylinositol-4,5-Bisphosphate-Containing Bilayers

“…Changes in hydration and thus viscosity of the adsorbed mass will lead to energy dissipation from the sensor surface. This is reflected by the dissipation change (DD ¼ D(t) -D 0 ), which can be used as an indicator for viscoelastic properties of the adsorbed mass and can be recorded in parallel during QCM-D measurements (32)(33)(34). The dissipation can be expressed as follows (Eq.…”

Importance of phospholipid bilayer integrity in the analysis of protein–lipid interactions

“…The measured frequency shift (DF = F(t) À F 0 ) is proportional to the adsorbed mass on the sensor surface [23,24] and the change in dissipation (DD = D(t) À D 0 ) is an indicator of the viscoelastic properties of the adsorbed layer or adlayer [24][25][26]. The formation of a supported bilayer involves several steps from vesicle adsorption, flattening, rupture and/or fusion and finally the formation of the bilayer [12].…”

Fabrication of an atrazine acoustic immunosensor based on a drop-deposition procedure

“…Thus, the viscoelastic properties of the layer coated (film modulus) on the crystal surface can be modified as well [28]- [30]. In addition, the modulus and mass contributions to frequency shift cannot be distinguished in a simple way, because both of them contribute to the decrease of the resonant frequency in a complex manner.…”