Mechanically Polished Titanium Surface for Immobilization of Hybrid Bilayer Membrane

In this work, hybrid bilayer lipid membrane (hBLM) was assembled on a mechanically polished metallurgical titanium plate. Hydrophobic molecular anchors needed for phospholipid overlayers were obtained by silanization of the Ti surface with octadecyltrichlorosilane (OTS). The formation of hBLM was accomplished by fusion of the multilamellar vesicles containing of 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cholesterol (Chol) at molar % ratio 60/40. The fusion process was monitored in real-time by the dynamic fast Fourier transformation (FFT) electrochemical impedance spectroscopy. We found that the repetitive regeneration of hBLM can be performed up to 4 times with no major loss of the electrochemical properties. Also, we showed that the electric barrier function of hBLMs is disrupted by phospholipase A2 (PLA2) - an enzyme, which hydrolyzes the fatty acid bonds at sn2 position in membrane phospholipids. Such effect may be used to design biosensors sensitive to both concentration and activity of the membrane damaging proteins, and possibly other agents.