Purine is a nitrogen-containing aromatic compound with a fused pyrimidine-imidazole ring structure which plays a crucial role in forming essential biological molecules: DNA, RNA. Current applications of purines are mainly focused on therapeutic and pharmaceutical areas for instance, anti-cancer therapy, antiviral drugs and bio-stimulation (caffeine) [1]. Beyond medical applications, purine-based derivatives with molecular D – A – D‘ structure show significant potential in metal ion sensing [2]. This important property of the purine compounds allows for the extension of application areas to use purine-based derivatives in environmental monitoring and chemical analysis.
Four purine derivatives (AIB – 137, AIB – 188, ZiK – 740, ZiK – 772) with two donor groups of different strength at positions C2 and C6 were under investigation for metal ion sensing purpose. Several characterization techniques were used, including steady-state absorption and fluorescence. Compounds of the AIB type were compared based on their efficacy in detecting tin (II) using acetonitrile as a solvent. The replacement of carbon atoms with oxygen in the carbon chains resulted in increased water solubility of ZiK type molecules. It was observed, that these purine derivatives are highly sensitive for silver (II) ions. Relatively more polar ZiK – 740 showed great potential for metal ion sensing inside living cells, which facilitates their use in biomedical applications.