Plasmonic nanoprobes gauging the length and flexibility of α,ω-Alkanedicarboxylic acids with an optical readout

Probing E/Z Isomerism Using Pillar[4]pyridinium/Gold Nanoparticle Ensembles and Their Photoresponsive Behavior

“…Among available pillar[n]pyridiniums, we chose the smallest one (P4P, Figure 1) due to its larger sensitiveness toward diacids. 23 To compile the sensor, both components were brought together to yield a colloid with C(P4P) = 4.5 mM and C(AuNPs) = 1 mM (in terms of gold). The excess of the macrocycle was necessary for the stabilization of the resultant colloid.…”

“…We demonstrated that small differences in the structure can be revealed using gold nanoparticles covered with cationic pillar­[ n ]­pyridinium macrocycles. , In the presence of carboxylic diacids, the nanoparticles approach one another by supramolecular interactions, resulting in plasmonic coupling, whose strength is proportional to the relative distance between carboxylic groups. In this manner, we were able to discriminate positional isomers and homologous carboxylic diacids . Herein, we report the differentiation of geometric isomers.…”

“…In this manner, we were able to discriminate positional isomers 22 and homologous carboxylic diacids. 23 Herein, we report the differentiation of geometric isomers. The method allows for the recognition of both single isomers and their multiple light-induced interconversion, which, apart from the optical response, leads to repetitive nanoparticle assembly and disassembly, representing a new promising direction for the utilization of geometric isomers.…”

“…Recently, we presented a nanoplasmonic platform 22,23 for probing various types of chemical similarity. We demonstrated that small differences in the structure can be revealed using gold nanoparticles covered with cationic pillar[n]pyridinium macrocycles.…”

“…Recently, we presented a nanoplasmonic platform , for probing various types of chemical similarity. We demonstrated that small differences in the structure can be revealed using gold nanoparticles covered with cationic pillar­[ n ]­pyridinium macrocycles. , In the presence of carboxylic diacids, the nanoparticles approach one another by supramolecular interactions, resulting in plasmonic coupling, whose strength is proportional to the relative distance between carboxylic groups.…”