Dear Colleagues,

The field of small-molecule optical sensors and probes is burgeoning with beautifully designed molecules that can signal the presence of an analyte—or a class of analytes—through changes in optical properties: i.e., absorbance, fluorescence or phosphorescence intensity, and chiroptical effects. While the field may be considered mature, most routine analytical works are still performed using expensive and cumbersome instrumentation; on the other hand, nonselective analytical techniques based on the separation of analytes from a complex matrix require delicate conditions and extensive calibration. For the first time since the birth of analytical chemistry techniques, chemists have the chance to synthesize molecules that do the hard work for us, targeting the analyte or analytes of interest, responding unequivocally to their concentration, and providing a signal readout that can be analyzed through very sensitive and relatively inexpensive instruments, photometers and fluorometers. Proper sensors—reversible systems that respond dynamically to variations in concentration of the analyte—and probes—that signal the maximum concentration of the analyte—are continuously developed for environmental monitoring of pollutants, for cellular imaging, and biomedical applications, such as the analysis of disease markers in body fluids. While selective sensors and probes are ultimately preferable in terms of sensitivity and interferences, in the past two decades, a marked shift has been observed toward the development of cross-reactive sensors and probes. When coupled with the power of pattern recognition and machine learning, a truly multi-analyte sensor platform is the preferred choice in high-throughput screening (HTS).

This Special Issue on Optical Sensors and Probes aims at collecting the latest and most innovative research in the field of sensing of gases and vapors, ions, small organic molecules, biologically relevant analytes, and disease markers using small-molecule colorimetric of fluorescent sensors and probes. You are invited to submit your original research papers, in the form of communications or full articles, topic or perspective reviews, including the latest and most original advances in regard to the current state-of-the-art in optical sensing. Topics may include but are not limited to:

• Sensing in water;
• Sensing in the intracellular medium/complex environmental and biological matrices;
• Sensing of metabolites/disease markers;
• Sensing of gases and volatiles;
• Sensing for the biomedical industry;
• Sensing of pollutants/radionuclides;
• Sensing for applications in food, pharmaceutical, and cosmetic products;
• Colorimetric sensing;
• Fluorometric sensing—fluorescence, phosphorescence, lifetime-based;
• Chiral sensing / enantiomeric excess determination;
• Cross-reactive sensor arrays for complex analytes and matrices.

Dr. Lorenzo Mosca
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sensors is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• sensor
• chemodosimeter
• probe
• indicator
• colorimetric
• fluorescence
• luminescence
• phosphorescence
• cross-reactive array
• pattern recognition
• sensing
• supramolecular sensor
• small-molecule sensor
• photoinduced electron transfer
• charge transfer
• energy transfer