Chemists are creating a brand new crystal type of the insecticide, growing its means to battle mosquitoes and malaria
By simply heating and cooling, New York University researchers created a new crystal form of deltamethrin – a widely used insecticide used to fight malaria – that results in an insecticide that is up to twelve times more effective against mosquitoes than the existing form.
The results, published in the journal Proceedings of the National Academy of Sciences (PNAS), could represent a much-needed and affordable alternative to insecticides, given the growing resistance of mosquitoes.
“Using more active crystal forms of insecticides is a simple and effective strategy to improve commercially available malaria control compounds to circumvent the need for new product development in the ongoing battle against mosquito-borne diseases,” said Bart Kahr, professor of chemistry at NYU and one of the study’s lead authors.
“Improvements to malaria control are still urgently needed during the global COVID-19 crisis,” added Kahr. “The number of deaths from malaria in Africa this year is expected to double due to supply chain disruptions related to coronavirus. We need public health action to curb both infectious diseases and, for malaria, that includes more effective insecticides. “
Malaria is a major public health challenge worldwide. More than 200 million cases and 400,000 deaths are reported each year. Insecticides like deltamethrin can prevent the spread of mosquito-borne diseases and are often sprayed indoors and on bed nets. However, mosquitoes are becoming increasingly resistant to insecticides, so researchers and public health officials are looking for alternatives with new mechanisms of action.
Many insecticides, including deltamethrin, are in the form of crystals – the focus of research for Kahr and his colleague, NYU chemistry professor Michael Ward. When mosquitoes step on insecticide crystals, the insecticide will be absorbed through their feet and, if effective, will kill the mosquitoes.
As part of their research on crystal formation and growth, Kahr and Ward study and manipulate insecticide crystals and explore their alternative forms. In their PNAS study, the researchers heated the commercially available form of deltamethrin to 110 ° C for a few minutes and allowed it to cool to room temperature. This resulted in a new crystallized form of deltamethrin made up of long, tiny fibers radiating from a single point.