Nanomaterial sensing: integrating MEMS technology and self-assembled monolayers

The integration of self-assembled monolayer (SAM) into microelectromechanical system (MEMS) devices is introduced in Chapter 1.
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nChapter 2 is concerned with the specific immobilization of NeutrAvidin on pure and mixed SAMs of biotinylated tri(ethylene glycol) undecanethiol (BUT, biotin containing sensor element for Neutravidin) and tetra(ethylene glycol) (TEG, spacer) which were deposited on Au surfaces. Contact angle, ellipsometry and XPS were used to characterize the composition of these SAMs. SPR and QCM were used to study the adsorption behavior of NeutrAvidin to the pure and mixed SAMs.
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nChapter 3 describes the optimum conditions in details of how to obtain the monolayer of 11-amino-1-undecanethiol hydrochloride (Alk-amine) and 4-aminothiophenol (Ar-amine) SAM, which were deposited on an Au surface by using an ethanolic solution of Triethylamine (TEA) and how to reduce the contamination which are combined with the deposition of the two amines. Finally, ellipsometry, contact angle and XPS were used to characterise the monolayer of two amine SAMs.
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nChapter 4 describes the optimum conditions of gold nanoparticles (G-NPs) deposition on a monolayer of Alk and Ar-amine terminated SAMs, which were described in chapter 3, at different pHs. AFM and QCM confirm that the optimum deposition of G-NPs was at pH 5 for the two amine SAMs and the deposition on Alk-amine SAM is much higher than on Ar-amine SAM. Thus, Alk-amine SAM was chosen for chemically modifying the surface of a micro paddle. After the modification the paddle was used to detect the deposited mass of G-NPs and SEM was used to confirm dispersity of the monolayer of G-NPs.