Quick Dips

From Catalysts to Cancer Cures

A toxic organophosphorus compound could have applications in areas as diverse as light-weight batteries and anti-cancer agents, according to work undertaken by Dr Bill Henderson of Waikato University's Chemistry Department.

Henderson is studying the synthesis of new organophosphorus compounds and their applications, concentrating on the water-soluble phosphine known as tris(hydroxymethyl)phosphine, or THP. It's a compound which has had relatively little work done on it, perhaps because of the highly toxic nature of the phosphine gas from which it is made, Henderson suggests. The chemical structure of THP means that it is a relatively straightforward matter to introduce other chemical functional groups, producing a range of potential applications.

"An example is the recovery of metals from aqueous solutions, which has applications in environmental chemistry and the recovery of precious metal catalyst residues," says Henderson.

In another area of research, Henderson is collaborating with Dr Nigel Sammes of Waikato's Centre for Technology in investigating the electrical properties of lithium-containing polymers, which can be prepared from THP.

"The materials have potential application in light-weight lithium batteries, for which there is currently a great deal of interest, particularly in the US and Japan," Henderson says.

Henderson is also working with Waikato University biochemist Dr Helen Petach in using THP in the synthesis of new types of polymers for immobilising enzymes.

"This immobilisation is highly desirable, since it allows the recovery of the often expensive enzyme by simple filtration, and offers potential for increasing the thermal and pH stability of the enzyme, as well as its longevity," Henderson remarks.

Immobilised enzymes have a wide variety of uses, such as in medical diagnostic kits, one type of which uses immobilised glucose oxidase to spot the presence of glucose in urine.

Other possible applications under study include using THP in the preparation of new phosphines which contain carbohydrates. These phosphines and their metal complexes -- particularly of platinum and gold -- may have interesting anti-cancer properties, according to Henderson. The Cancer Society of New Zealand is intrigued by this prospect and is supporting the study.

One side benefit to the work is the diverse research areas it brings together.

"The projects by their very nature are interdisciplinary, and I believe that this is where many new discoveries in science remain to be made," says Henderson.