Coalescing Nanotechnology and Microbreweries

Researchers succeed in synthesizing carbon quantum dots from brewery wastes.

FREMONT, CA: Quantum dots, frequently referred to as manufactured atoms, are employed in the transmission of light. This kind of nanotechnology has been employed successfully as a sensor in biomedicine or as LEDs in next-generation displays. It possesses a variety of intriguing physicochemical features. However, there is a downside. Present-day quantum dots are made from heavy, hazardous metals like cadmium. Because it is readily available and biocompatible, carbon is an intriguing alternative. Daniele Benetti, a postdoctoral fellow at INRS, and Aurel Thibaut Nkeumaleu, the master's student at ÉTS who carried out the work, suggested using brewery waste as a raw material. They essentially intended to do numerous experiments with readily available materials. This is how the scientists and the Brasseurs de Montréal came to work together to collect their cereal remnants. The fact that brewery waste is naturally concentrated in nitrogen and phosphorus makes it a good source of carbon quantum dots. By doing this, pure chemicals are not required. From a circular economy standpoint, the utilisation of leftover grain exemplifies both an eco-friendly approach to waste management and alternative raw material for the synthesis of carbon quantum dots.

The goal of the study team was to demonstrate that carbon quantum dots may be produced using conventional techniques in addition to biobased materials. The scientists turned the used grain into a black powder by carbonising it in a standard microwave oven. After that, it was combined with distilled water and returned to the microwave. To obtain the quantum dots, a centrifuge passage and sophisticated filtration were required. In addition to other contaminants that have an impact on water quality, the environment, and human health, their finished product was able to identify and measure heavy metals. Beyond proof of concept, the basic process will involve characterising these carbon quantum dots made from brewery waste. The study group is sure that this nanotechnology has the potential to develop into very advanced aqueous solution detecting sensors, even inside live cells.

Spent grain, the cereal waste from breweries, has been utilised in animal feed for several years. This substance may soon also be utilised in nanotechnology! The research group of Professor Federico Rosei at the Institut national de la recherche Scientifique (INRS) has demonstrated the viability of using brewing waste as a carbon source for the synthesis of quantum dots. The project was completed in cooperation with Claudiane Ouellet-Plamondon of the École de Technologie supérieure (ETS), and it was published in the RSC Advances journal of the Royal Society of Chemistry.