Bioprocessing 4.0 relies on better sensors. In the department of chemical engineering at Imperial College London, Karen Polizzi, PhD, professor of biotechnology, and her colleagues use synthetic biology to make in vivo sensors that can be used in bioprocessing.
Polizzi and her team developed bacteria as sensors that can detect the concentration of waste products in a culture. These bacterial sensors “are very sensitive and specific, especially when compared with chemical approaches for detection,” Polizzi explains. Nonetheless, these sensors didn’t work in cocultures with mammalian cells because the bacteria grow so much faster that they consume most of the food in a culture. “After a relatively brief period of time, the mammalian cells would die out completely,” Polizzi says.
To use the bacterial sensors in the past, Polizzi’s team took a sample of the mammalian culture and added the bacterial sensors to analyze the waste product levels. That process, though, limited the frequency of using the sensors.
In a recent article, Polizzi and her colleagues described using LAMPS (living analytics in a multilayer polymer shell) in cocultures of bacterial sensors and mammalian cells. Polizzi says that LAMPS are “a way of sequestering bacteria so that they can grow alongside mammalian cells without doing any damage to them.” Plus, LAMPS allow Polizzi’s team “to use the bacterial analytical devices in the cultures in real-time, which will improve our understanding of what is going on in the mammalian culture and make it easier to make adjustments while cells are growing to improve production.”
Now, Polizzi hopes to make these sensors useful in commercial bioprocessing. “We are focused on how to make them on a large scale and how to quality control batches so we are sure they will function reliably,” she says. “I think this is a key step to getting industrial uptake.”
