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 A 2 (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.

No abstract

In this work mixed hybrid phospholipid bilayers (mhBLM) were deposited on fluorine doped tin oxide (FTO) films. Two component silane‐based self‐assembled monolayers (SAMs) formed on FTO surface trigger vesicle fusion and formation of mhBLMs which are stable, can be easily regenerated, and therefore, used for multiple experiments. We found that certain chemical and physical conditions under which mixed SAMs are fabricated translate into functional properties of mhBLMs. In all cases we observed interaction of melittin with mhBLMs demonstrating biological relevance of these biomimetic surface constructs and their possible application in biosensors for toxin detection.

In this work we describe the functionalization of metallurgically polished aluminum surfaces yielding biomimetic electrodes suitable for probing protein/phospholipid interactions. The functionalization involves two simple steps: silanization of the aluminum and subsequent fusion of multilamellar vesicles which leads to the formation of a hybrid bilayer lipid membrane (hBLM). The vesicle fusion was followed in real-time by fast Fourier transform electrochemical impedance spectroscopy (FFT EIS). The impedance-derived complex capacitance of the hBLMs was approximately 0.61 µF cm−2, a value typical for intact phospholipid bilayers. We found that the hBLMs can be readily disrupted if exposed to > 400 nM solutions of the pore-forming peptide melittin. However, the presence of cholesterol at 40% (mol) in hBLMs exhibited an inhibitory effect on the membrane-damaging capacity of the peptide. The melittin-membrane interaction was concentration dependent decreasing with concentration. The hBLMs on Al surface can be regenerated multiple times, retaining their dielectric and functional properties essentially intact.

No abstract