Alkyl ammonium ion-induced drastic emission enhancement of Eu(D-facam)3 in 1-butanol

Drastic enhancements in both emission intensity and circular polarization of a Eu(iii) complex were achieved in 1-butanol solution in the presence of alkylammonium ions.

Recognition and optical sensing of amines by a quartz-bound 7-chloro-4-quinolylazopillar[5]arene monolayer

Pillar[5]arene-decorated quartz slides for the direct detection of linear amines and diamines are now available.

Olefin epoxidation by a (salen)Mn(iii) catalyst covalently grafted on glass beads

A newly synthesized robust (salen)Mn(iii) monolayer on glass bead substrates provides an active catalyst for asymmetric epoxidation of 6-cyano-2,2-dimethylchromene, cis-β-ethylstyrene, 1,2-dihydronaphthalene and indene.

Enantioselective extraction mediated by a chiral cavitand–salen covalently assembled on a porous silicon surface

A chiral organic–inorganic hybrid device shows enantioselection properties in water solution towards bromine-marked alkyl-ammonium salts.

Functionalization of SnO₂ crystals with a covalently-assembled porphyrin monolayer

The functionalization of micro- and nano-sized metal-oxide powders offers many advantages because of their large surface areas and, therefore, the large number of functional molecules that can be grafted onto the grain surfaces. Porphyrin molecules on large band-gap semiconducting metal oxides represent key materials for many different optical and electronic applications. Herein, we have proposed a general two-step procedure for the functionalization of metal-oxide crystals with dye-sensitizers. In particular, we functionalized SnO₂ nanoparticles with a monolayer of the bifunctional trichloro[4-(chloromethyl)phenyl]silane. Then, a monolayer of 5,10,15,20-tetrakis(4-hydroxyphenyl)-21H,23H-porphyne was covalently bound to the silanized SnO₂ grains. IR, UV/Vis, and luminescence measurements were used for optical characterization. The measured footprint of the grafted porphyrin molecules indicated total surface coverage of the grains. The surface electronic characterization was performed by using X-ray photoelectron spectroscopy. Emission measurements revealed two strong bands at 664.1 and 721.0 nm that were attributed to the porphyrin monolayer assembled on the surface of the SnO₂ crystals.

Exclusive recognition of sarcosine in water and urine by a cavitand-functionalized silicon surface

A supramolecular approach for the specific detection of sarcosine, recently linked to the occurrence of aggressive prostate cancer forms, has been developed. A hybrid active surface was prepared by the covalent anchoring on Si substrates of a tetraphosphonate cavitand as supramolecular receptor and it was proven able to recognize sarcosine from its nonmethylated precursor, glycine, in water and urine. The entire complexation process has been investigated in the solid state, in solution, and at the solid-liquid interface to determine and weight all the factors responsible of the observed specificity. The final outcome is a Si-based active surface capable of binding exclusively sarcosine. The complete selectivity of the cavitand-decorated surface under these stringent conditions represents a critical step forward in the use of these materials for the specific detection of sarcosine and related metabolites in biological fluids.