MIT Develops a Vibrant Activity Sensor

【China Instrument Network Instrument Development】 An interdisciplinary team at the Massachusetts Institute of Technology (MIT) has created a new type of active sensor by combining the special properties of hydrogels (up to 95% water) with Genetically modified living cells make them resilient and biocompatible, and they emit light when they encounter certain chemicals.


The researchers created different wearable sensors from cell-infused hydrogels, including rubber gloves with finger cuffs that glow after touching a chemically contaminated surface, and a bandage that is applied to the skin of a person and pressed. It glows when it comes to chemicals.

The study, published in the most recent issue of the National Academy of Sciences (NAS), shows that this new material has the potential to sense chemicals in the environment and in the human body.

According to Xuanhe Zhao, an associate professor of mechanical engineering at MIT, this hybrid "active material" is suitable for sensing a variety of different chemical substances and contaminants, ranging from crime scene investigation and forensic science to pollution monitoring and medical diagnosis. Although hydrogels are effective in confining living cells to moist and nutrient-rich environments, they are also tough and biocompatible enough to be designed together with other flexible rubber materials to create versatile biochemical sensors. .

In the past, scientists could only store live cells in culture dishes in a carefully controlled environment, making it difficult to exploit the fluorescent nature of living cells in synthetic materials. In this study, researchers first used 3D printing and micro-molding techniques to create hydrogel layers and patterned narrow channels.

Then, the researchers fusing the hydrogel to a layer of elastic pores, allowing oxygen to enter and injecting E. coli cells into the channel, causing it to fluoresce when in contact with certain chemicals that allow the hydrogel to pass through. Immersing the hydrogel/elastic mixture in a nutrient solution such that the entire hydrogel is filled with nutrients can maintain bacterial cells viable and active for several days.

This hybrid material can be embedded in narrow channels and can be designed to react to various biochemical substances (each chemical can be designed to have a corresponding light-emitting bacteria in Chengdu) to create a wearable patch or a sensory tip. Gloves. The "active patch" responds by sensing the respective chemically sensitive substance.

The research team also developed a theoretical model to help guide other researchers in designing similar active materials and equipment. Zhao anticipates that this glove or rubber sole lined with a chemical sensing hydrogel or bandage can be used to detect signs of infection or disease.

(Original title: Poison-emitting active sensor is expected to be used for crime scene investigation)