Researchers at Yale University created a wearable air sampler clip that can be worn on clothing and which can bind aerosols present in the environment. The clip can later be analyzed to determine the level of SARS-CoV-2 exposure while it was worn. The low-cost, battery-free technology could allow people to identify unsafe indoor environments that may require additional safety measures. While the design does not allow for real time viral monitoring, its low cost and ease of use could make it a simple way to improve viral safety in workplaces and healthcare facilities.
As we learn to live with SARS-CoV-2, our tactics for dealing with it have changed. In the early days of the pandemic, when vaccines were not available, many countries opted for severe lockdowns and restrictions on movement coupled with basic sanitary practices, such as hand washing. Now, with the rise of the less severe, but more transmissible Omicron variant, vaccine coverage, rapid testing, and mask wearing have all come to the fore.
Part of this effort involves making indoor environments more COVID-safe. Increasing air movement and ventilation could help to reduce a build up of virus-laden aerosols and in the future more advanced solutions, such as air filters for decontamination, could become commonplace.
Identifying where the virus tends to accumulate indoors is also key in reducing transmission and modifying indoor spaces so that they are as safe as possible. One method involves actively sampling the air to spot viral particles. However, active air samplers are typically large, expensive and require a power source. These researchers have created a low-cost passive alternative that can be worn on clothing throughout the day and then analyzed using PCR later to determine personal exposure levels for the wearer.
The researchers have called their device the Fresh Air Clip and it consists of a polydimethylsiloxane (PDMS) surface that can continually bind virus-laden aerosols throughout the day. So far, the researchers have tested the device inside a machine that generates aerosols that are similar to those produced when people talk, cough, sneeze, or sing. The aerosols contained a surrogate virus that is much safer to work with than SARS-CoV-2, and the researchers were successfully able to detect the virus on the clips using PCR.
Finally, a group of 62 volunteers put the clips to the test “in the wild” and wore them for 5 days while going about their normal business. The researchers subsequently detected SARS-CoV-2 in five clips, four of which were worn by restaurant servers, highlighting the high viral exposure levels of people working in the service industry.
Study in Environmental Science & Technology Letters: Development and Application of a Polydimethylsiloxane-Based Passive Air Sampler to Assess Personal Exposure to SARS-CoV-2