Scientists in the US have used zinc coordination compounds to recognise pathogenic bacteria. 

Bradley D Smith at the University of Notre Dame and colleagues investigated a series of low molecular weight zinc(II) complexes. Two of the complexes could be used to discriminate between common pathogenic bacteria, such as Escherichia coli and Staphylococcus aureus, and mammalian cells. 

The team produced images of bacteria, bound by the complexes, using fluorescence microscopy. The complexes show an affinity for the anionic surfaces of the bacteria, Smith suggested. The compounds could offer a new avenue for drug targeting and imaging for bacterial sites of infection, he said.

Zinc(II) coordination complexes can be easily manipulated and modified, according to Smith. In particular, they can be attached to magnetic nanoparticles or immobilised filters and can be used to remove bacteria from blood. 

The team are now working on improving the stability of the zinc(II) complexes so that they can be employed in living systems. 'Our primary concern is maintaining the integrity of our coordination complexes in the blood, which contains serum and cleaning systems that remove foreign agents', said Smith.

Jenna Wilson