For next-generation smart devices, autonomy is key. These devices will be able to power themselves, independently respond to stimuli, and perform different kinds of work, all without human intervention. With these abilities, smart devices could potentially have very wide-reaching implications.
In a recent study published in Nature Chemistry, Samudra Sengupta, et al., from The Pennsylvania State University, the Ural Branch of the Russian Academy of Sciences, and the University of Puerto Rico-Mayagüez, have designed and demonstrated a self-powered enzyme micropump that autonomously delivers small molecules and proteins in response to specific chemical stimuli.
"We demonstrate that surface-anchored enzymes can act as pumps in the presence of their respective substrates, pumping fluid and particles in a directional manner," coauthor Ayusman Sen, Professor of Chemistry at Penn State, told Phys.org. "This discovery enables the design of non-mechanical, self-powered nano/microscale pumps that precisely control flow rate and turn on in response to specific stimuli. One example described in the paper is the release of insulin from a reservoir at a rate proportional to ambient glucose concentration."
As a proof-of-principle, the researchers demonstrated how an enzyme micropump can be used to pump out insulin in response to the glucose concentration in the surrounding solution. A similar process occurs in the pancreas of healthy individuals, and afterwards the increased insulin stimulates muscle and fat cells to absorb the increased amounts of glucose from the blood.
However, in individuals with Type 1 diabetes, the pancreas does not produce sufficient amounts of insulin in response to elevated blood sugar levels. By autonomously releasing insulin in response to glucose concentration, the enzyme micropump essentially fulfills this role of the pancreas.