Thanks to micro-cameras in a special hydrogel, it is possible to study the behaviour of these insects (which is sometimes dangerous, because they transmit diseases) in previously unattainable detail.
Although how different species of mosquitoes bite humans (and many other mammals, reptiles and birds) has long been known, there are still many aspects to be clarified. And it is precisely these grey areas that have so far prevented the development of truly effective substances and devices to stop these insects attacking.
As well as being annoying and causing possible irritation, certain types of mosquitoes, especially common in tropical areas, can also transmit diseases like malaria, dengue, yellow fever, Zika, West Nile fever, Chikungunya and many more (the incidence of which is increasing worldwide due to climate change).
Now, however, understanding the behaviour of these insects, and what drives them to bite so that they can feed and reproduce, may improve greatly, thanks to a high-tech synthetic skin developed in the US by researchers at Tulane University (New Orleans) and Rice University (Houston). The results of this study have been published in the scientific journal Frontiers in Bioengineering and Biotechnology.
In a nutshell, researchers have created a transparent hydrogel, with a similar consistency to skin, with a series of tiny channels like blood vessels, heated and filled with the blood of some of the mosquitoes' favourite animals: mainly cattle and sheep.
This synthetic skin (which in reality has very little in common with biological skin) was created by a CAD (computer-aided design) system and a 3D printer.
The synthetic skin is linked to a micro-camera for each ‘block’ of hydrogel so that mosquito behaviour can be recorded in great detail. The images captured are then transmitted to an AI system, which processes them and continuously fine-tunes the conditions to be optimal, or adjusts the presence of substances that interfere with the ability to suck blood. Everything is placed in a transparent box, which attracts the mosquitoes, who are then left free so that they behave normally.
During the tests, three different types of mosquitoes appeared to be able, among other things, to distinguish between blood and various control liquids that were very similar in colour and consistency: they always chose blood. The researchers then 'tested' some substances that can repel the parasites, and more will be tested in the future.
Beyond animal testing
The new device can be adapted to any hematophagous insect (one that feeds on blood), and can be used to test various repellent substances, as well as to study mosquito behaviour in a detail that is impossible to achieve with animal models (so, in this case at least, animal experimentation has been outperformed by technology).