Can plastic recycling be fixed?

CHEMICAL TECHNOLOGY

Article | June 11, 2021

An enzyme-mimicking catalyst opens a new route to important organic molecules such as glycolic acid and amino acids from pyruvate, report researchers in Japan. Moreover, the new catalyst is cheaper, more stable, safer and more environmentally friendly than conventional metal catalysts used in industry, they note, adding that it also displays the high enantioselectivity required by the pharmaceutical industry. “On top of these advantages, our newly developed organic catalyst system also promotes reactions using pyruvate that aren’t easily achievable using metal catalysts,” says Santanu Mondal, a PhD candidate in the chemistry and chemical bioengineering unit at Okinawa Institute of Science and Technology (OIST) Graduate University, Okinawa, Japan, and lead author of a study recently published in Organic Letters. “Organic catalysts, in particular, are set to revolutionize the industry and make chemistry more sustainable,” he stresses. The researchers use an acid and an amine mixture to force the pyruvate to act as an electron donor rather than its usual role as an electron receiver (Figure 1). Effectively mimicking how enzymes work, the amine binds to the pyruvate to make an intermediate molecule. The organic acid then covers up part of the intermediate molecule while leaving another part that can donate electrons free to react to form a new product. Currently, the organic catalyst system only works when reacting pyruvate with a specific class of organic molecule called cyclic imines. So, the researchers now are looking to develop a more-universal catalyst, i.e., one that can speed up reactions between pyruvate and a broad range of organic molecules. The challenge here is to try to make the electron-donating intermediate stage of pyruvate react with other functional groups such as aldehydes and ketones. However, different catalysts create different intermediates, all with different properties. For example, the enamine intermediate created by the researchers’ new reaction only reacts with cyclic imines. Their hypothesis, currently being investigated, is that creation of other intermediates such as an enolate, if possible, would achieve a broader pyruvate reactivity. In terms of cost, the researchers note that a palladium catalyst used in similar reactions is 25 times more expensive than their organic acid — which also is made from eco-friendly quinine. In addition, they believe scale-up of the process for industrial use definitely is possible. However, the researchers caution that the current amine-to-acid-catalyst loading ratio of 1:2 probably would need to be optimized for better results at a larger scale.

SCIENCE AND RESEARCH

Article | June 27, 2021

The landscape of biological and chemical logistics has changed rapidly - as have the regulatory frameworks around it. What has not necessarily kept pace is the end-user understanding of the nature of these logistical processes, their opportunities and their constraints. Twenty years ago, the transmission of biological and chemical materials was limited to a small range of organisations: usually national and international research companies, hospitals, major university departments, police and military departments with forensic responsibilities.

CHEMICAL MANAGEMENT

Article | June 13, 2021

The modern world is built on chemicals, be it the medicines we use, or cleaning fluids, crop protection products, or the raw materials for everything from laptops and mobile phones to clothes and furniture. Across all, we have created an entire modern society with chemicals, and, as a result, constantly stretched the size of the world population we can feed, clothe and shelter. Yet, balancing all the gains from the modern chemistry around us against any negative environmental and human impact has been a rising concern, making for ever greater focus on testing and on risk assessment.

Article | February 11, 2020

Everyone is very familiar with the phrase when buying a house: All that really matters are three things - location, location, and location. This same principle applies to extractables and leachables chemistry analysis – the three things that truly matter are identification, identification, and identification. The greatest growth in the past ten years in demonstrating the safety of medical devices and container closure systems for drugs has been using analytical chemistry to determine what chemicals can leach from the device and what the patient is exposed to during its intended use.