Self-assembled dithiothreitol on Au surfaces for biological applications: phospholipid bilayer formation

TÂNIA BEATRIZ CRECZYNSKI-PASA; MARÍA ANTONIETA DAZA MILLONE; MAXIMILIANO LUIS MUNFORD; VÂNIA RODRIGUES DE LIMA; TIAGO OPALA VIEIRA; GUILLERMO A. BENÍTEZ; ANDRÉ AVELINO PASA; ROBERTO C. SALVAREZZA; MARÍA ELENA VELA

PHYSICAL CHEMISTRY CHEMICAL PHYSICS

ROYAL SOC CHEMISTRY

Año: 2009 vol. 11 p. 1077 - 1084

1463-9076

Self-assembly of dithiothreitol (DTT) on Au(111) from solution deposition has been studied by X-ray photoelectron spectroscopy and electrochemical data. DTT molecules self-assemble on Au(111) in a lying-down configuration irrespective of the concentration and temperature. XPS and electrochemical data indicate a DTT surface coverage of theta = 0.16 with two S-head–Au covalent bonds per DTT molecule. The DTT monolayer turns the Au surface hydrophilic enough to allow the formation of fluid dimyristoylphosphatidylcholine (DMPC) bilayer domains by vesicle fusion as revealed by in situ atomic force imaging. Methylene blue (MB) and flavin adenine dinucleotide (FAD) have been used as probes to study molecule transport across the bilayer.