Schematic diagram showing cooling of nanopores by charge-selective ion transport. Credit: 2023 Tsutsui et al., Peltier Cooling for Thermal Management of Nanofluidic Devices, Devices, ed.
Groundbreaking work by Japanese researchers demonstrates nanopore-mediated cooling, revolutionizing temperature control in microfluidic systems and deepening our understanding of cellular ion channels.
Have you ever wondered how water boils in an electric kettle? Most people may think that electricity just heats a metal coil inside the kettle and transfers that heat to the water. . But electricity can do so much more. When electricity causes ions in a solution to flow, heat is generated. If all ions and surrounding molecules are free to move, this heating effect will be uniform throughout the solution. Now, Japanese researchers have investigated what happens if this flow is blocked in one direction.
Cooling with nanopore technology
In a recently published study, deviceA team led by researchers at Osaka University’s SANKEN (National Institute of Scientific and Industrial Research) has shown that cooling can be achieved by using nanopores (very small holes in membranes) as gateways that allow only certain ions to pass through. Through.
In general, when electricity is used to drive ions in a solution, positively charged ions and negatively charged ions are attracted in opposite directions. Therefore, the thermal energy carried by the ions travels in both directions.
Understanding ion flow and temperature control
If the path of the ions is blocked by a membrane that can only pass through the nanopores, it becomes possible to control the flow. For example, if the pore surface is negatively charged, negative ions can interact without passing through, and only positive ions will flow with energy.
“At high ion concentrations, we measured an increase in temperature as the power increased,” explains study lead author Mayu Tsutsui. “However, at low concentrations, the available negative ions interact with the negatively charged nanopore walls. Therefore, only positively charged ions passed through the nanopore and a decrease in temperature was observed. ”
Applications in microfluidics and cell biology
The demonstrated ionic cooling could potentially be used to cool microfluidic systems, setups used to move, mix, or interrogate very small volumes of liquids. Such systems are important across many fields, from microelectronics to nanomedicine.
Additionally, this discovery could help further our understanding of ion channels, which play a key role in the delicate balance mechanisms of cells. Such insights could be key to understanding function and disease and designing treatments.
Broader implications and future prospects
“We are excited about the breadth of the potential impact of our findings,” says Yuji Kawai, lead author of the study. “There is considerable scope to tune nanopore materials to tune cooling. Additionally, arrays of nanopores can be created to amplify the effect.”
The list of areas that could be enhanced by this discovery is indeed considerable, extending to the use of temperature gradients to generate electrical potentials. This has potential applications in temperature sensing and blue power generation.
References: “Peltier Cooling for Thermal Management in Nanofluidic Devices” by Mayu Tsutsui, Kazumichi Yokota, Wei Lung Su, Dennis Garoli, Hirofumi Oguji, and Yuji Kawai, December 5, 2023. device.
DOI: 10.1016/j.device.2023.100188
Source: scitechdaily.com
