Ferrocene is a so-called sandwich complex consisting of an central iron (II) ion and two cyclopentadienyl rings on opposite sides. The azido modification allows this compound to be bond to any alkyne-/DBCO-modified biomolecule by click chemistry.

The ability to oxidize this complex to ferrocenium makes it an ideal marker for electrochemical detection (EC probes). For example, ferrocene modified oligos can be detected with HPLC-ECD methods in the sub-femtomole range. Due to these properties, EC probes have the potential to be a cost-effective alternative to fluorescence-based probes in clinical or medical diagnostic, e.g. for DNA microarray systems.

In a recent study, ferrocene azide was also used for the development of electrochemical biosensors based on graphene nanoribbons. Additionally, ferrocene shows high stability against heat, basic pH and hydrolysis which enables subsequent reactions or long-time storage. An advantage in contrast to fluorescent labeled oligos, which are slowly destroyed after detection. Ferrocene-modified oligos can be analyzed or measured more frequently.

LITERATURE

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