SPR Biosensing MUA/Poly-L-lysine Platform for the Detection of 2,4-Dinitrophenol as Small Molecule Model System

M. A. DAZA MILLONE; EDUARDO A. RAMIREZ; CECILIA Y. CHAIN; ANDREA CRIVARO; DAVID ROMANIN; MARTIN RUMBO; GUILLERMO DOCENA; MAURO COCCO; MARIA L. PEDANO; ALEJANDRO FAINSTEIN; JORGELINA MONTOYA; MARIA E. VELA; ROBERTO C. SALVAREZZA

JOURNAL OF NANOMATERIALS

HINDAWI PUBLISHING CORPORATION

Lugar: New York; Año: 2016 vol. 2016

1687-4110

Surface Plasmon Resonance assays are being developed as alternative biodetection methods for a great number of pesticides andtoxins.These substances typically have low molecular weight, making it necessary to perform competitive inhibition immunoassays.In most of the cases, the strategy is to immobilize a protein derivative of the analyte, which usually involves the appearanceof nonspecific protein binding which limits the detection range of the assay. In this work we present results of a poly-L-lysine(Au-MUA-PLL) based sensor platform for quantitative determination of 2,4-dinitrophenol as model system for small molecularweight substances detection. The prepared sensor chip was characterized by means of Atomic Force Microscopy, Surface PlasmonResonance, and Surface Enhanced Raman Spectroscopy. Experiments verified the absence of nonspecific protein adsorption toAu-MUA-PLL surfaces and the improvement of the competitive inhibition assays performance in comparison with single andmixed thiol self-assembled monolayers. The possibility of directly immobilizing 2,4-dinitrophenol to the poly-L-lysine containingplatforms leads to an improvement in the detection of the soluble analyte by the competitive inhibition assay avoiding undesirablenonspecific protein adsorption.Therefore, Au-MUA-PLL surfaces constitute a suitable alternative for quantitative detection of smallmolecules when nonspecific adsorption cannot be avoided.