Project Summary/Abstract The goal of this proposed NIH SBIR Phase II program will be to continue development and commercialization of a new noninvasive transdermal alcohol monitor. The monitor will be in wristband or watch form, similar to a smartwatch. This device will be modern, attractive and comfortable and will have smartwatch features including measuring key physiological parameters (e.g., pulse) with wireless communication to apps on smartphones and other devices. The aim of the work is to provide a new, noninvasive transdermal alcohol monitor into the market. The transdermal alcohol monitoring market has few wearable products available and innovation has been lacking in this field. This new product will take advantage of current trends in wearable technology. As the public becomes more comfortable with wearables, the blood alcohol monitor will become popular with people interested in health and fitness who want to track their alcohol intake. The product will provide a new, highly reliable and sensitive method for tracking blood alcohol which will eventually be adopted in other areas, including clinical and medical treatment and employee wellness programs. The device is expected also to provide a more effective system than is currently available for alcohol research. The monitor is based on the KWJ Engineering?s printed electrochemical gas sensor. This ethanol sensor is very small, ultralow power and highly sensitive with very low interferences. These characteristics provide a sensor that is more effective than those used in current technologies. Additionally, because of its size and power requirements, it is the only gas sensor available that is compatible with modern applications such as the watch format of this proposal. In Phase I, we demonstrated stable and sensitive measurement of ethanol across human skin surrogate membranes with a first prototype wristwatch device that included the ethanol sensor and circuitry for performing the measurement and converting data for wireless communication to a computer. Raw transdermal ethanol concentrations (TAC) were calibrated to blood alcohol values using standardized ethanol solutions as a surrogate for blood alcohol concentration (BAC). We demonstrated a high degree of reproducibility across several watch format devices. In Phase II, development of the device will be continued in collaboration with partners specializing in wearable systems and product development. A small human trial will be conducted to evaluate the wearability and functionality of the Phase II prototype device.