Synthesis of 'lab-on-a-molecule' systems for medical diagnostics

Abstract

The multi-step synthesis of a novel two-input sensor for sodium ions and protons was achieved. This two-input sensor is a precursor towards the development of a novel three-input 'Lab-on-a-Molecule (LOAM). A number of key intermediate reactions were achieved and the products characterized by 1H NMR, 13C NMR and IR spectroscopy, as well as GC-MS and melting point determination techniques. Even though two intermediate steps proved to have high yields (98% and 88%), others had 15% yields which made the synthesis of the LOAM synthetically challenging. Preliminary studies of the novel two-input sensor show an enhancement factor (FE) of 8 at near neutral pH and FE of 36 at pH 3. Through a fluorescent pH titration experiment, the pKa of this molecule was also found to be 5.8. A synthetic scheme for another novel LOAM was proposed, which involved a 'one-pot' strategy to minimise the synthetic steps. This route indicates that the 'one-pot' approach is a viable option to be considered when designing such supramolecular molecules.