In a study, published Thursday in the journal Angewandte Chemie, researchers from the Eindhoven University of Technology described the creation of a “mini-factory” of drugs contained within artificial leaves. These structures, which don’t necessarily need to be shaped like leaves, utilize the unique characteristics of luminescent solar concentrators (LSCs) — materials capable of capturing sunlight much like real leaves, converting it to a specific color, and guiding it to where it’s needed.
“Using sunlight to make chemical products has long been a dream of many a chemical engineer. The problem is that the available sunlight generates too little energy to kick off reactions,” the Eindhoven University of Technology said in a statement released Wednesday. “However, nature is able to do this. Antenna molecules in leaves capture energy from sunlight and collect it in the reaction centers of the leaf where enough solar energy is present for the chemical reactions that give the plant its food.”
In order to recreate this process using synthetic materials, the researchers created very thin channels in a silicon rubber LSC through which the chemicals needed to manufacture the drugs were pumped. The LSC then amplified the sunlight intensity to such an extent that it triggered a chemical reaction in the liquids flowing through the channels — the raw materials enter from one side, light causes the reactions, and the end product, the required drug, comes out through the other channels.
“Even an experiment on a cloudy day demonstrated that the chemical production was 40 percent higher than in a similar experiment without LSC material,” lead researcher Timothy Noël said in the statement. “We still see plenty of possibilities for improvement. We now have a powerful tool at our disposal that enables the sustainable, sunlight-based production of valuable chemical products like drugs or crop protection agents.”
Although the experiment is still largely in its proof-of-concept stage and it would be years before it can be scaled up to a level where it’s economically viable and efficient, the researchers believe that by using visible light, the reactions needed to manufacture drugs can become much cheaper and countless times faster.
“Using a reactor like this means you can make drugs anywhere, in principle, whether malaria drugs in the jungle or paracetamol on Mars. All you need is sunlight and this mini-factory,” Noël said.
