Synthetic molecular probes, chemosensors, and nanosensors used in combination with innovative assay protocols hold great potential for the development of robust, low-cost, and fast-responding sensors that are applicable in biofluids (urine, blood, and saliva). Particularly, the development of sensors for metabolites, neurotransmitters, drugs, and inorganic ions is highly desirable due to a lack of suitable biosensors. In addition, the monitoring and analysis of metabolic and signaling networks in cells and organisms by optical probes and chemosensors is becoming increasingly important in molecular biology and medicine. Thus, new perspectives for personalized diagnostics, theranostics, and biochemical/ medical research will be unlocked when standing limitations of artificial binders and receptors are overcome. In this review, we survey synthetic sensing systems that have promising (future) application potential for the detection of small molecules, cations, and anions in aqueous media and biofluids. Special attention was given to sensing systems that provide a readily measurable optical signal through dynamic covalent chemistry, supramolecular host− guest interactions, or nanoparticles featuring plasmonic effects. This review shall also enable the reader to evaluate the current performance of molecular probes, chemosensors, and nanosensors in terms of sensitivity and selectivity with respect to practical requirement, and thereby inspiring new ideas for the development of further advanced systems.

A conceptual sensor array for the efficient discrimination and fast detection of saturated alkanes and commonly found volatile solvents is reported.

Fast, sensitive and selective detection of diamines in the vapor phase is of pivotal importance for air and food quality monitoring. In this work, an electron-poor fluorophore, perylene bisimide (PBI), was modified with hydrophilic residues at its bay positions, resulting in an amphiphilic derivative, PEBBO. Photophysical studies revealed that the compound shows a strong aggregation tendency in various solvents, but the aggregates could be highly fluorescent provided suitable solvents are used. Accordingly, a fluorescent film was constructed via utilization of the well-known Langmuir-Blodgett technique. Sensing performance studies revealed that the film as prepared is sensitive and selective to the presence of diamines in air. Specifically, (1) the experimental detection limit is lower than 0.016 g m and the linear range of the analysis extends from 0.33 g m to 8.20 g m when ethylenediamine was adopted as an example analyte; (2) the presence of other amines and solvents shows little effect upon detection; (3) the response time is less than 5 s. Considering the importance of diamine sensing, the convenience of fluorescence techniques and the superiorities of the film and method as developed, it is believed that the present work is of great importance for promoting technical progress in diamine sensing.