Chemical Sensors and Imaging: Molecular, Materials, and Biological Platforms

From the invisible gases that make up the air we breathe, to the nanoscopic and microscopic molecules of life that make up the central dogma of DNA to RNA to proteins, to the metal ions and metabolites that shape cell behavior from firing of action potentials of neurons or triggering cell growth and death pathways in cancer and infectious diseases, sensors can make the invisible visible and help us understand and better our daily lives. (4−6) This situation is due in large part to the avoidance of specialized genetic modification techniques and the small size of molecular payloads compared to protein tags, which minimize perturbations within the biological systems being investigated. The development of small-molecule sensors able to measure biorelevant analytes or enzyme activity through activity-based sensing strategies remains an area of intense research interest. Cy5 labeled G-SNAT proved successful in measuring gzmB activity in CAR T treated lymphoma tumor-bearing mice. [...]G-SNAT was used in combination with bioluminescence imaging to measure the effectiveness of combination therapies, notably anti-PD-1 and anti-CTLA-4, in colorectal tumor-bearing transgenic mouse models expressing firefly luciferase via multimodal imaging.