Amino-functionalized monolayers covalently grafted to silica-based substrates as a robust primer anchorage in aqueous media

作者：Giraud Lucie; Nadarajah Rakini; Matar Yasmine; Bazin Gwenaelle; Sun Jing; Zhu X X; Giasson Suzanne^*

来源：Applied Surface Science, 2016, 370: 476-485.

DOI：10.1016/j.apsusc.2016.02.141

• Monolayer
• Silane
• Hydrolytic stability
• Grafting density
• Surface coverage

Controlling surface coverage and stability of supported aminoalkylsilane monolayers on silica-based substrates still remains a challenge for the development of biosensors and nanomaterials. We have developed protocols using simple surface chemistry and self-assembly from solution without stringent deposition conditions to covalently attach monolayers of 11-aminoundecyltriethoxysilane (AUTES) onto mica and silica substrates. The resulting self-assembled monolayers (SAMs) exhibited excellent hydrolytic stability. The long alkyl chain together with the large grafting density and homogeneity enhanced the monolayer stability by preventing the Si-silane-O-Si-surface bonds from hydrolysis over a wide range of pH values (2-10) for long time periods (up to 8 days). The control over the surface density of amino groups was achieved and the reactivity of the amino SAMs was confirmed by covalently attaching carboxyl-functionalized nanoparticles on the SAMs. The immobilized nanoparticles exhibited the same hydrolytic stability as that of the SAMs. The AUTES SAMs prepared in this study exhibited the best hydrolytic stability of similar systems reported so far.

• 出版日期2016-5-1