Polymer-Based Sensor for Cortisol Detection in Sweat

Our project 

Cortisol is known as the stress hormone as it is elevated during periods of psychological stress. Monitoring and controlling cortisol levels has implications for managing stress-related diseases and has shown to be advantageous for optimizing athletic performance. Many cortisol sensors have been developed using technologies such as surface plasmon resonance, liquid chromatography, and molecularly selective nonporous membrane that have shown preliminary success. Still, challenges are associated with making them flexible and small enough to be used in commercial settings. To combat this, we developed a polymer that can specifically detect cortisol from sweat. Unlike other methods, this polymer uses no biologics, allowing it to be reusable and resistant to environmental conditions (heat, moisture, etc.). 

Our inspiration 

Lululemon approached us with the proposal to develop a sweat cortisol sensor that can eventually be integrated into clothing. They presented applications in monitoring and increasing athletic performance, but after doing research and interviews, we noticed the implications in so many supplemental settings such as workplace stress management and chronic stress patients. Having something that can be non-invasive and seamlessly integrated into people's lives has a greater potential of being widely adopted and makes it accessible to everyone. This technology can also be adapted for other single-molecule detection in biological and non-biological applications. For example, having a method for single-molecule detection can be translated to point-of-care diagnostics, which will increase the accessibility of testing and enables more timely clinical decision-making. Working on a robust method of detecting cortisol in sweat was rewarding, but learning the applications this technology may have in the future was truly inspiring. 

Our biggest challenge 

Many of the challenges were faced early in the project when we determined a promising approach to solving the problem but had a lack of knowledge of how to execute our solution. The expertise required for this project was widely in polymer chemistry, something our team was not experienced in. Due to the field of single-molecule detection being relatively new, we were not able to find the information and knowledge we needed online. To understand the topic more deeply and develop the laboratory protocols, we needed to contact experts in the field. Luckily, we had access to a large network of chemists and chemical engineers at UBC and found advisors who had expertise in polymer chemistry. Finding the right people to talk to was challenging, and not having direct access to answers often added delays to our timeline. 

What excited us most 

We are most excited about fabricating a sensor. We started this project knowing nothing about polymer. The learning curve was exponential for us, yet it is what excites us the most. Previously we had only integrated sensors into systems, but in this project, we had the opportunity to fabricate the sensor. Learning and getting hands-on experience in the field of single-molecule detection has been a great opportunity, and we look forward to its development in the future. 

The most interesting/surprising thing we learned 

We are most surprised by the data we gathered from our test, which shows a relationship between cortisol concentration and electrical signal. We never thought we could get such optimistic results with our limited knowledge and experience. There is a lot more testing and development yet to be done, but it was still very encouraging to see that our method shows a favourable initial result. Thus, we learned that you do not need to have the necessary knowledge or expertise to get favourable results. All you need is the eagerness to learn and dedication to the project. 

Our project's future 

We hope to continue developing our method and perform more testing. And hopefully, in the future, we will see cortisol sensors integrated into Lululemon garments.