The first reaction cuts open the SARS-CoV-2 virus’ membrane to expose its RNA. The final product consists of three different freeze-dried biological reactions that are sequentially activated by the release of water from a reservoir via the single push of a button. The team called upon every resource they had available to them at the Wyss Institute to create their COVID-19-detecting face masks, including toehold switches developed in Core Faculty member Peng Yin’s lab and SHERLOCK sensors developed in the Collins lab.
It was definitely different from the usual lab infrastructure we’re used to working under, but everything we did has helped us ensure that the sensors would work in real-world pandemic conditions,” said co-first author Luis Soenksen, Ph.D., a Postdoctoral Fellow at the Wyss Institute. We worked hard, sometimes bringing non-biological equipment home and assembling devices manually. The entire project was done under quarantine or strict social distancing starting in May 2020. “We wanted to contribute to the global effort to fight the virus, and we came up with the idea of integrating wFDCF into face masks to detect SARS-CoV-2. He and his teammates started investigating whether their wFDCF technology could solve this problem, methodically testing it in more than 100 different kinds of fabrics. If that aquarium ever broke, then the engineered bugs could leak out onto the wearer, and nobody likes that idea,” said Nguyen. “Other groups have created wearables that can sense biomolecules, but those techniques have all required putting living cells into the wearable itself, as if the user were wearing a tiny aquarium. Credit: Wyss Institute at Harvard University These flexible, wearable biosensors can be integrated into fabric to create clothing that can detect pathogens and environmental toxins and alert the wearer via a companion smartphone app. Following their success embedding their biosensors into paper, they next set their sights on making them wearable.
They created biosensors that can detect pathogen-derived RNA molecules and coupled them with a colored or fluorescent indicator protein, then embedded the genetic circuit into paper to create a cheap, accurate, portable diagnostic. The researchers first applied this technology to diagnostics by integrating it into a tool to address the Zika virus outbreak in 2015.
Synthetic genetic circuits can be added to create biosensors that can produce a detectable signal in response of the presence of a target molecule. These biological elements are shelf-stable for long periods of time and activating them is simple: just add water. The technique involves extracting and freeze-drying the molecular machinery that cells use to read DNA and produce RNA and proteins. The SARS-CoV-2 biosensor is the culmination of three years of work on what the team calls their wearable freeze-dried cell-free (wFDCF) technology, which is built upon earlier iterations created in the lab of Wyss Core Faculty member and senior author Jim Collins. “In addition to face masks, our programmable biosensors can be integrated into other garments to provide on-the-go detection of dangerous substances including viruses, bacteria, toxins, and chemical agents.” Taking cells out of the equation “We have essentially shrunk an entire diagnostic laboratory down into a small, synthetic biology-based sensor that works with any face mask, and combines the high accuracy of PCR tests with the speed and low cost of antigen tests,” said co-first author Peter Nguyen, Ph.D., a Research Scientist at the Wyss Institute. The wearer pushes a button on the mask that releases a small amount of water into the system, which provides results within 90 minutes.
The wFDCF face mask can be integrated into any standard face mask. The achievement is reported in Nature Biotechnology. The button-activated mask gives results within 90 minutes at levels of accuracy comparable to standard nucleic acid-based diagnostic tests like polymerase chain reactions (PCR). The team has integrated this technology into standard face masks to detect the presence of the SARS-CoV-2 virus in a patient’s breath. But what if cutting-edge biotechnology were integrated into your clothing, and could warn you when you were exposed to something dangerous?Ī team of researchers from the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Massachusetts Institute of Technology has found a way to embed synthetic biology reactions into fabrics, creating wearable biosensors that can be customized to detect pathogens and toxins and alert the wearer. Most people associate the term “wearable” with a fitness tracker, smartwatch, or wireless earbuds.