Researchers have synthesized a sensitive molecular probe that can detect different phosphate molecules in living cells1. The probe gives off distinct optical signals when it binds to different phosphate molecules and so can be used to obtain useful insights into biochemical reactions in living cells.

The researchers synthesized the probe by allowing self-assembly of naphthalenediimide modified with zinc-containing dipicolylethylenediamine receptors. They examined how the molecular probe behaved and generated specific optical signals on binding to different phosphate molecules in aqueous solutions.

The researchers found that when the molecular probe bond to various forms of phosphate molecules, it produced helical structures through self-assembly. In addition, it also gave off unique optical signals.

The scientists observed that the optical signals produced by the probe decreased when the adenosine triphosphate it was bound to was converted to adenosine diphosphate or adenosine monophosphate. Thus, a reduction in signal intensity indicates a depletion of adenosine triphosphate molecules in solution, implying that the probe could be used to monitor biochemical reactions.

The molecular probe could potentially be used in a sensor that enters cells and binds to intracellular adenosine triphosphate, generating optical signals, which will change during the course of biochemical reactions. The researchers say that, by reading out the changes in optical signals, this sensor could be used to monitor various cellular processes in real time.