What if highly interesting events take place but you will not be able to investigate – because the actors are too
small to be observed? And there is nobody to tell you about either?
That’s why ten years ago A. W. Czarnik stated to be „desperately seeking sensors” for biology, chemistry, or materials
science investigations. There were a lot of biologically active small molecules for which detectors, e.g. fluorescent sensors,
would be desirable: neurotransmitters (NO), ATP, amino acids, nucleosides, nucleotides, carbohydrates, coenzymes, inorganic phosphate,
Just the easiest way by far would be a device that combined both the interaction „platform“ and the sensing system. In general, chemical
sensors require transducing a binding event into an easily quantitated signal event. Although it is possible to use absorption or
electrical changes as the signal, fluorescent signaling offers real advantages. Because fluorescence emission occurs at a different
wavelength than excitation, the background signal can be made very low and the sensitivity thus very high.