Self-Assembly of Pyridine-Modified Lipoic Acid Derivatives on Gold and Their Interaction with Thyroxine (T4)

International Journal of Molecular Sciences

Willem M. Albers¹  Roberto Milani¹  Kirsi Tappura¹  Tony Munter¹  Giuseppe Resnati² 

[1] VTT Technical Research Centre of Finland, Sinitaival 6, 33720 Tampere, Finland & Metallimiehenkuja 8, Espoo, 02044 VTT, Finland; E-Mails:;NFMLab-DCMIC “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, I-20131 Milano, Italy; E-Mail:

关键词: thyroxine;    self-assembly;    imprinting;    noncovalent interactions;    Surface Plasmon Resonance (SPR);   

DOI  :  10.3390/ijms14023500

来源: mdpi

【 摘 要 】

Pyridyl derivatives of lipoic acid were prepared as ligands for the study of the interaction with thyroxine (T4). Thin self-assembled films of the ligands were prepared in 70% ethanol on gold and their interaction with T4 was studied by titration experiments in an aqueous buffer solution using Surface Plasmon Resonance (SPR). The thickness and refractive index of the ligand layers were calculated from SPR spectra recorded in two media, also allowing for surface coverage and the density of the layers to be estimated. Two ligands, a 4-pyridyl and a bis(2-hydroxyethyl) derivative of lipoic acid, were selected to investigate the feasibility for producing molecularly imprinted self-assembled layers on gold for T4. The methodology was to co-assemble T4 and the ligand onto the gold surface, elute the T4 from the layer under alkaline conditions, and study the rebinding of T4 to the layer. Multiple elution/rebinding cycles were conducted in different buffer solutions, and rebinding of T4 could be observed, with a moderate binding affinity that depended greatly on the solvent used. More optimal binding was observed in HBS buffer, and the affinity of the interaction could be slightly increased when the 4-pyridyl and bis(2-hydroxy-ethyl) derivatives of lipoic acid were combined in the imprinted layer.

【 授权许可】

CC BY   
© 2013 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.