Our bodies require a healthy balance of electrolytes in order to function properly. Normal sodium levels in the blood hover at around 135-145 mM, and levels that fall below this range are characterized as hyponatremia. Hyponatremia occurs in 15-30% of hospitalized patients and often in people who have taken part in endurance sporting events. Depending on how severe it is, symptoms can range from headaches and confusion to seizures and even coma. Hyponatremia is typically diagnosed through invasive blood tests or urine sodium tests, both of which require lab testing with priority-based classifications and, thus, long turnaround time.

Microneedle patches are arrays of microscopic needles that can be applied to the skin in a minimally invasive fashion. While microneedle technology is still in its developing stages, it has potential for applications in drug delivery and biosensing for a variety of detections. We are particularly interested in exploring the exciting possibilities of what microneedle patches can do to facilitate the process of detecting sodium levels in the body.

For our microneedle patch, we selected a commercially available fluorophore called CoroNa Green, which is mostly used in studies of cell behaviour. While there is data available for the ability of CoroNa Green to detect sodium, we wanted to validate it ourselves before moving forward with it. After conducting selectivity and sensitivity tests, the results showed that CoroNa Green is a suitable fluorophore to detect sodium. We could then start on the design experiments!

We need to conduct further research to confirm the effectiveness and accuracy of the patch for detecting sodium levels, as well as quantify the reproducibility of our procedures, which can be quite challenging.

In comparison to traditional testing methods, microneedles present a more patient-friendly option for measuring levels of biomarkers like sodium in a non-invasive way with a simple application process. We envision that the use of this product could help reduce the amount of waste and energy that goes into a typical blood or urine test, as well as reduce the burden placed on healthcare providers by facilitating the process of monitoring patients. The microneedle patch is quite small, made of biocompatible materials, and requires a much smaller sample volume than lab testing currently used. The goal of our project is to improve the detection, and, consequently, the treatment of hyponatremia to address its $1.6 – 3.6 billion USD annual burden in the US. Overall, through the work that we’ve done with this project, we hope to contribute to the advancement of technologies for more accessible detection and treatment of relevant conditions within the healthcare system.