Addressing the surface chemistry of silicon is of fundamental scientific and technical significance due to the wide use of this material in electronics and optics. A novel method of functionalizing silicon (Si) via short peptides with binding specificity for Si is presented. The peptide presenting the highest affinity for Si is identified via phage display technology, and the 12‐mer LLADTTHHRPWT and SPGLSLVSHMQT peptides were found to be specific for the n+‐Si and p+‐Si surfaces, respectively. In our sensing application, the obtained peptides are used as functionalizing linkers to allow porous silicon microcavities to bind biotin and then capture streptavidin. Molecular detection is monitored via reflectometric interference spectra as shifts in the resonance peaks of the cavity structure. An improved streptavidin sensing (21 times lower detection limit) with peptide‐functionalized porous silicon microcavities is demonstrated, compared to sensing performed with devices functionalized with the commonly used silanization method, suggesting that the modification of Si via Si‐specific peptides provides better interface layers for molecular detection. High‐resolution atomic force microscopy images corroborate this result and reveal the formation of ordered nanometer‐sized molecular layers when peptide‐route functionalization is performed.

We experimentally investigated second harmonic generation from an oriented multilayer film of bacteriorhodopsin protein, deposited onto a charged surface. The generated signal is obtained as a function of incidence angle, at different polarization state of both fundamental and generated beams. We show that the measurements, together with the analytical curves, allow to retrieve the nonvanishing elements of the nonlinear optical tensor, including the ones introduced by optical chirality.

Progression of enzymes in lignocellulosic biomass is a crucial parameter in biorefinery processes, and it appears to be one of the limiting factors in optimizing lignocellulose degradation. In order to assay the importance of the chemical and structural features of the substrate matrix on enzyme mobility, we have designed bioinspired model assemblies of secondary plant cell walls, which have been used to measure the mobility of fluorescent probes while modifying different parameters (probe size, water content, polysaccharide concentration). The results were used to construct a model of probe mobility and to rank the parameters in order of importance. Water content and probe size were shown to have the greatest effect. Although these assemblies are simplified templates of the plant cell walls, our strategy paves the way for proposing new approaches for optimizing biomass saccharification, such as selecting enzymes with suitable properties.

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