Hydrophobic perfluoro-silane functionalization of porous silicon photoluminescent films and particles

Luminescent structures based on semiconductor quantum dots (QDs) are increasingly used in biomolecular assays, cell tracking systems, and in-vivo diagnostics devices. The functionalization of such structures with capping molecules providing controlled interaction with proteins is of main relevance. In this work we have carried out the functionalization of porous silicon (PSi) luminescent structures by a perfluorosilane (Perfluoro-octyltriethoxysilane, PFOS) self assembly. The PFOS surface binding (traced by X-ray photoelectron spectroscopy) and photoluminescence efficiency were analyzed on flat model PSi. Maximal photoluminescence intensity was obtained from PSi layers anodized at 100 mA/cm2. Resistance to hydroxylation was assayed in H2O2: ethanol solutions and evidenced by water contact angle (WCA) measurements. PFOS functionalized PSi presented systematically higher WCA) than untreated PSi. Confirmation of PFOS binding to PSi particles was derived from FTIR spectra. The PFOS functionalization was found to slightly improve the aging of the PSi particles giving rise to particles with longer luminescent life. Such functionalization opens the possibility of promoting hydrophobic-hydrophobic interactions between biomolecules and fluorescent QD structures, which may enlarge their therapeutic or diagnostics catalogue.

C Rodriguez;  P Laplace;  GALLACH PÉREZ D.;  PELLACANI Paola;  R.J. Martin Palma;  TORRES COSTA V.;  CECCONE Giacomo;  MANSO Miguel; 

2016-06-14

ELSEVIER SCIENCE BV

JRC100477

0169-4332,   

http://www.sciencedirect.com/science/article/pii/S0169433216001562,    https://publications.jrc.ec.europa.eu/repository/handle/JRC100477,   

10.1016/j.apsusc.2016.01.119,