Aminosilane functionalizations of mesoporous oxidized silicon for oligonucleotide synthesis and detection

Abstract

Direct solid phase synthesis of peptides and oligonucleotides (ONs) requires high chemical stability of the support material. In this work, we have investigated the passivation ability of porous oxidized silicon multilayered structures by two aminosilane compounds, 3-aminopropyltriethoxysilane and 3-aminopropyldimethylethoxysilane (APDMES), for optical label-free ON biosensor fabrication. We have also studied by spectroscopic reflectometry the hybridization between a 13 bases ON, directly grown on the aminosilane modified porous oxidized silicon by in situ synthesis, and its complementary sequence. Even if the results show that both devices are stable to the chemicals (carbonate/methanol) used, the porous silica structure passivated by APDMES reveals higher functionalization degree due to less steric hindrance of pores.

Quantification and Reduction of the Residual Chemical Reactivity of Passivated Biodegradable Porous Silicon for Drug Delivery Applications

“…Its medical biodegradability and biocompatibility [7][8][9], widely tuneable pore sizes via electrochemical etching [10,11], flexible surface chemistry [12,13] and high payloads of nanostructured drugs [14] are its key attributes in this regard. However, biodegradable materials are generally, almost by definition, more chemically reactive than "bio-inert" ones.…”

A new strategy for label-free detection of lymphoma cancer cells

“…Red shifts of spectra both for APTES and BS 3 modification were observed. The phenomenon was due to the formation of a thin film of chemical substances on pore walls, which increased the average refractive indices of PSi layers [22]. In particular, a red shift of 21 nm was registered after APTES treatment and of 15 nm after BS 3 .…”

“…After silanization, excess of unbound silanes was removed by rinsing sample three times in toluene dry for 2 min. Last step of silanization process was curing on a heater at 100°C for 10 min [22].…”

Bioengineered Surfaces for Real-Time Label-Free Detection of Cancer Cells

“…Reflectivity spectra on porous silicon surface before (solid line) and after APTES silanization (dashed line), and after BS Reflectivity spectra of porous silicon devices during functionalization steps are reported in Figure 5. The deposition on pores walls of a thin layer, constituted by the different organic chemical compounds, produces red shifts of spectra due to the increase of the average refractive index of porous silicon surfaces [57]. After silanization and cross-linker modification, a red shift of 21 and 15 nm was recorded, respectively.…”