The consequence of physical and mental degraded performance is of critical importance not only to the Department of Defense (DoD) missions and sports persons, but also to the general population as well. Sweat is an information abundant medium that contains biomarkers that show relation to human cognitive levels. However, obtaining days of continuous sampling of sweat from the same dermal spot has proved challenging. Hence, there is a need for a sweat sensor patch that can capture sweat samples in a chronological manner, measure sweat rate, blocks contaminants, conform to the skin, and continuously reports sweat biomarkers.TDA Research proposes to develop and demonstrate a modular microfluidic sweat sensor patch that has the capability to not only carry out real-time monitoring of select biomarkers but also collect multiple precisely time stamped chronological samples for off-line analysis in laboratory assays.