Nano-sensors for listening to the 'conversation' of bacteria

(Nanowerk News) At the laboratory of Dr. Luis Liz Marzán, Ikerbasque researcher and Scientific Director at CIC biomaGUNE, they are developing an ambitious research project, known as ‘Plasmaquo’, aimed at developing a sensor which enables detecting the molecules that are released by bacteria to communicate with each other and, thus, understanding their paths of communication. This project has a budget of 2.3 million euros, provided by the European Research Council (ERC) and which places the CIC biomaGUNE biomaterials research centre at the vanguard of research in this field.
Luis Liz Marzan Group
Luis Liz Marzan Group
The study of communication amongst bacteria and their coordinated behaviour once these organisms reach a minimum critical size has great potential for applications such as the diagnosis of illnesses and even, potentially, the development of therapeutic agents.
Science has already demonstrated that bacteria act collectively when a minimum ‘quorum’ is reached, i.e. once a determined number of ‘individuals’ is arrived at. By means of a mechanism technically known as “quorum sensing”, the bacteria secrete certain molecules and are capable of detecting the concentration of these particles in their surroundings in order to know if the minimum ‘quorum has been reached to start the meeting.
The sensor developed by Dr Liz’s team is based on the amplification of a signal which is characteristic of molecules involved in quorum sensing. To obtain the amplification, the sensor employs the chemical manufacture of gold nanoparticles and their organization in ordered structures, which respond to light in a characteristic manner.
The scientific community has been working on the use of nanoparticles in detection applications for two decades now, but researchers still have not found materials that enable undertaking detection trials in a completely reliable and reproducible way. This is why the work by CIC biomaGUNE is focusing on new materials and their application to cell cultures and colonies of bacteria.
In the opinion of Dr Liz, “The end goal is the development of a device that can be employed not only in CIC biomaGUNE, but also in other research teams involved in studying systems of biomedical interest. One of the difficulties of the process is the need to detect what are miniscule amounts of molecules involved in these processes. Another complication is molecules have to be distinguished one from each other, such as proteins or fats, making their measurement furthermore onerous”.
When these difficulties are overcome, the sensor technology will be able to be used in new systems of diagnosis that can help identifying diseases at their early stages, and thus be treated more effectively.
“The approach of this research is entirely multidisciplinary, given that it requires the participation of specialists in chemistry responsible for the manufacture and handling of nanoparticles, physicists who design the detection methods, and biologists responsible for the handling of cell and bacterial cultures”, stated Dr Liz.
Source: University of Wisconsin-Madison