This Small Business Innovation Research (SBIR) Phase I project will create a new way to deliver certain fluids, such as intravenous drugs. Small dose dispensing ($35.63 billion annual global market) is a vital activity across many different industries including pharmaceuticals, medical devices, and consumer products (e.g. flavors & fragrances). Firms in these sectors are creating highly valuable concentrated liquids and need to deliver extremely small volumes in an efficient, accurate, and precise manner to minimize lost materials and ensure the safety of their customers and integrity of their product. Current dispensing technologies create a bottleneck in the manufacturing process by inhibiting parallel dispensing, or are too costly to justify the value they provide. This project advances a sterilizable, highly accurate, and resource-efficient solution to deliver small amounts of many types of fluids with up to 20-fold increase in throughput, 75% footprint reduction, and 95% reduction in cost without compromising accuracy or precision. These properties directly meet the needs in several industry segments such as pharmaceutical dispensing, scientific research, and manufacturing. The intellectual merit of this project is to advance a method of elastic filament velocimetry (EFV), which utilizes a strain-based sensor to measure the velocity of fluid passing over a free-standing, electrically-conductive nanoscale ribbon. Drag from the passing flow deflects the nanoribbon and induces an axial strain and a change in the resistance that is directly related to flow. The small dimensions of the sensing element result in viscously-dominated drag force, enabling sensitivity to both liquids and gases. Most commercial strain-based sensors utilize calibrated cantilevers or plates embedded with strain gauges on one or more surfaces before the entire member is calibrated to the fluid velocity. The current approach combines the calibrated member and strain gauge into a single unit, eliminating the most complicated and expensive aspects of previous designs. The project will further enhance this technology by exploring more accessible nanoribbon materials, quantifying sensor drift over time, characterizing response to differing fluid properties, and define operating parameters by exposing the sensor to non-ideal conditions. At the conclusion of the project, the sensors will have defined calibration and operating parameters and will be suitable for use with a wide array of fluids, including injectables. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
