Analyst Blog

Terephthalate as a probe for photochemically generated hydroxyl radical

Terephthalate picks up an OH radical to form fluorescent hydroxyterephthalate

Sarah E. Page, William A. Arnold and Kristopher McNeill, J. Environ. Monit., 2010, 12, 1658
DOI: 10.1039/c0em00160k

A sensitive probe to monitor hydroxyl radicals in water has been developed by a team of Swiss and US scientists.
Current hydroxyl radical probes, such as benzoic acid, often have limited sensitivity, require long irradiation times or high concentrations of the probe, which can affect the sample.  Now Kristopher McNeill at the Swiss Federal Institute of Technology (ETH) in Zurich and colleagues at the University of Minnesota in Minneapolis have discovered that terephthalate is a more sensitive probe for hydroxyl radicals in aquatic environments.

Read Rachel Cooper’s full news article at Highlights in Chemical Technology.

Inhibiting acetylcholinesterase alters the growth of nanoparticles causing a colour change

A paper-based colorimetric dipstick bioassay that can detect low levels of pesticides has been developed by John Brennan and colleagues at McMaster University in Hamilton, Canada.

You can access the paper via the Analyst homepage.

Organophosphate pesticides can be toxic to both humans and animals as they inhibit important enzymes such as acetylcholinesterase (AChE) in the nervous system.  They are still in widespread use so there is a need for a simple method to detect their residues.  Now, Brennan’s team has created a gold nanoparticle-based dipstick test to identify inhibitors of the acetylcholinesterase enzyme that would be easy to use for in-field applications.

Brennan says he hopes to develop this system by ‘integrating the various reagents involved in the assay into a single lateral flow device, which should avoid the need for adding external reagents’.  His group are also ‘investigating other enzymes that are known to support catalytic growth of gold nanoparticles to further evaluate this sensor platform’.

To read the full story, head to Highlights in Chemical Technology.