By Gary Thomas
A team of engineers led by Harvard presented a plan to develop self-thermoregulating nanomaterials, which can be customized in order to maintain a set pressure, pH, or any other required parameter by fulfilling the ecological alterations with the help of chemical feedback response.
A strategy for building self-regulating nanomaterials relies on an array of tiny nanofibers, akin to little hairs, embedded in a layer of hydrogel.
The newly formed materials platform called self-regulated mechano-chemical adaptively reconfigurable tunable system (SMARTS) provides a tailored way for turning chemical reactions on and off independently and to recreate dynamic feedback loops that are self powered in biological systems.
This advancement marks a shift towards efficient and intelligent medical implants and also dynamic buildings that can possibly react to the weather for improved energy efficiency
The structure of SMARTS is similar to a microscopic toothbrush, featuring bristles that can lie down or stand up, making contact and breaking the same with a layer comprising chemical ‘nutrients’. SMARTS works as same as goosebumps. Homeostasis cannot be easily reproduced in synthetic materials, when compared to natural materials like skin that can regulate and maintain control in various environments.
Ximin He, a postdoctoral fellow in the Aizenberg lab at SEAS and at the Wyss Institute, stated that SMARTS can be specifically designed to detect and alter the required stimulus, pressure, pH level, wetness or temperature, with no complex machinery or external power, providing a new robust, reversible, and customizable platform.
Ximin He and the team selected temperature as stimulus and an array of minute nanofibers were embedded in a hydrogel layer in order to demonstrate SMARTS. When there is a change in temperature, the hydrogel can contract or swell. When there is drop in temperature, the gel swells and the hairs stand vertically and establish a contact with the ‘nutrient’ layer. When the temperature is warm, the gel shrinks, and the hairs lie in the downward direction. The main feature is that molecular catalysts when positioned on the nanofibers’ tips can set off chemical reactions, which produce heat, in the ‘nutrient’ layer.
The technique, when refined further, may possibly be integrated into materials for use in medical implants, in order to control bodily functions.
Ximin He added that anything like light, heat, mechanical pressure can be turned into a chemical signal in the gel. Similarly, the reactions that are activated by the moving hairs can potentially generate various kinds of compensatory responses. A variety of self-regulating feedback loops can be formed by harmonizing signals and responses.
SMARTS is a perfect “laboratory” to learn about the basic properties of chemical and biological systems.