Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada.
Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada.
Proc Natl Acad Sci U S A. 2020 Mar 3;117(9):4632-4641. doi: 10.1073/pnas.1916562117. Epub 2020 Feb 18.
Point-of-care diagnostic assays often involve multistep reactions, requiring a wide range of precise temperatures. Although precise heating is critical to performing these assays, it is challenging to provide it in an electricity-free format away from established infrastructure. Chemical heaters are electricity-free and use exothermic reactions. However, they are unsuitable for point-of-care multistep reactions because they sacrifice portability, have a narrow range of achievable temperatures, and long ramp-up times. Here we developed a miniature heater by modulating the lithium-water reaction kinetics using bubbles in a channel. Our heaters are up to 8,000 times smaller than current devices and can provide precise (within 5 °C) and tunable heating from 37 °C to 65 °C (∆T = 12 °C to 40 °C) with ramp-up times of a minute. We demonstrate field portablity and stability and show their use in an electricity-free multistep workflow that needs a range of temperatures. Ultimately, we envision providing better access to cutting edge biochemical techniques, including diagnostics, by making portable and electricity-free heating available at any location.
即时诊断检测通常涉及多步反应，需要大范围的精确温度。虽然精确加热对执行这些检测至关重要，但在没有既定基础设施的情况下，很难提供无电格式的加热。化学加热器是无电的，并利用放热反应。然而，它们不适合即时诊断多步反应，因为它们牺牲了便携性，实现的温度范围狭窄，且升温时间长。在这里，我们通过在通道中使用气泡来调节锂水反应动力学，开发了一种微型加热器。我们的加热器比目前的设备小 8000 倍，可以提供精确的（在 5°C 以内）和可调的加热，从 37°C 到 65°C（∆T=12°C 到 40°C），升温时间为一分钟。我们展示了野外便携性和稳定性，并展示了它们在无电多步工作流程中的使用，该流程需要一系列温度。最终，我们设想通过在任何地点提供便携和无电加热，为包括诊断在内的更先进的生化技术提供更好的获取途径。
