Protein attachment to silane-functionalized porous silicon: A comparison of electrostatic and covalent attachment

Malgorzata Baranowska, Agata J. Slota, Pinkie J. Eravuchira, Maria Alba, Pilar Formentin, Josep Pallarès, Josep Ferré-Borrull, Lluís F. Marsal

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12 Citations (Scopus)


Porous silicon (pSi) is a prosperous biomaterial, biocompatible, and biodegradable. Obtaining regularly functionalized pSi surfaces is required in many biotechnology applications. Silane-PEG-NHS (triethoxysilane-polyethylene-glycol-N-hydroxysuccinimide) is useful for single-molecule studies due to its ability to attach to only one biomolecule. We investigate the functionalization of pSi with silane-PEG-NHS and compare it with two common grafting agents: APTMS (3-aminopropylotrimethoxysilane) as electrostatic linker, and APTMS modified with glutaraldehyde as covalent spacer. We show the arrangement of two proteins (collagen and bovine serum albumin) as a function of the functionalization and of the pore size. FTIR is used to demonstrate correct functionalization while fluorescence confocal microscopy reveals that silane-PEG-NHS results in a more uniform protein distribution. Reflection interference spectroscopy (RIfS) is used to estimate the attachment of linker and proteins. The results open a way to obtain homogenous chemical modified silicon supports with a great value in biosensing, drug delivery and cell biology.

Original languageEnglish
Pages (from-to)180-189
Number of pages10
JournalJournal of Colloid and Interface Science
Publication statusPublished - 5 Aug 2015
Externally publishedYes


  • Bovine serum albumin
  • Collagen
  • GTA
  • Porous silicon
  • Reflection interference spectroscopy (RIfS)
  • Silane-PEG-NHS

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