Self-Assembled Monolayers from Symmetrical Di-Thiols: Preparation, Characterization and Application for the Assembly of Electrochemically Active Films

1,3-dimercaptopropan-2-ol, a symmetrical di-thiol, has been synthesized and applied as new type of anchor molecule to prepare self-assembled monolayer (SAM) on gold surface. The formed monolayers were studied by cyclic voltammetry, impedance spectroscopy, X-ray photoelectron kinetic capacitance, contact angle measurements. SAM structure depends the adsorption conditions. A short incubation time electrode at high concentration this di-thiol leads predominating binding through one thiol group adsorbate surface, while long low both groups. comparative study desorption replacement SAMs indicates strong stability increase when molecules bond surfaces two bonds mainly. This was used immobilize electrochemically active p-benzoquinone moiety. surface obtained from voltammetry is 2.5 ± 0.2 × 10−10 mol cm−2, which corresponds functionalization 65 5% molecules. highly stable with redox-active terminal can be for different tasks chemical sensing biosensing. As an example, application system electrocatalytical oxidation dihydronicotinamide adenosine dinucleotide (NADH) tested.