Fused silica-capillaries were successfully functionalised with spiropyran-polymer brushes using spiropyran functionalised norbornyl derivative as monomer. The polymerisation was achieved by surface-initiated ringopening metathesis polymerisation. A three-dimensional arrangement, covalently attached to the inner wall of the fused-silica capillary, was obtained. The spiropyran moiety has the freedom to open and close in response to light (ultraviolet, white light) within the polymer brushes. The coating was fully characterised by Scanning Electron Microscopy, absorbance measurements and kinetic studies. The photo-response of the coatings showed very good reproducibility comparable with spiropyran monomers in solution demonstrating that this platform can be used for the develop of capillary integrated sensors based on the inherited sensing proprieties of spiropyran moieties.

Cobalt and its alloys are used in a broad range of application fields. However, the use of this metal is especially limited by its strongly oxidizable nature. The use of alkanethiol self-assembled monolayers (SAMs) is a very efficient way to protect against such oxidation and/or to inhibit corrosion. This surface modification method has been particularly applied to oxidizable metals such as copper or nickel, yet the modification of cobalt surfaces by alkanethiol SAMs received limited attention up to now. In this work, we study the influence of parameters by which to control the self-assembly process of 1-dodecanethiol monolayers on cobalt: nature of the surface pretreatment, solvent, immersion time, and concentration. Each of these parameters has been optimized to obtain a densely packed and stable monolayer able to efficiently prevent the reoxidation of the modified cobalt substrates. The obtained monolayers were characterized by X-ray photoelectron spectroscopy (XPS), polarization modulation infrared reflection-absorption spectroscopy, and contact angle measurements. The stability of the optimized 1-dodecanethiol monolayer upon air exposure for 28 days has been confirmed by XPS.

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