This Small Business Technology Transfer (STTR) Phase II project, in collaboration with North Carolina State University, will develop and validate an innovative, mobile, multiwavelength pulse oximetry module for noninvasive health monitoring of various blood metabolites simultaneously in real time. At the heart of this pulse oximetry module will be a novel multiwavelength emitter having independent control of up to nine spectrally narrow wavelengths, ranging from blue to mid-IR, emitting from a single 1 mm2 LED die. In contrast with traditional dual-wavelength pulse oximetry, which measures oxygen saturation in the blood, the proposed multiwavelength LED will enable real-time analysis several additional metabolites critical to health monitoring via the same noninvasive paradigm. Furthermore, the individually controlled self-aligned wavelengths enable superior motion artifact cancellation, which is essential for eHealth and mobile fitness applications. The key objectives of this feasibility study are to: Demonstrate luminescent films with peak emissions from 400-1100 nm Integrate these films into a compact multiwavelength pulse oximetry module Optimize novel pulsing algorithms for multiwavelength pulse oximetry Validate the mobile multiwavelength pulse oximetry module in a lab setting
The medical impact of dual-wavelength pulse oximetry, in both saving lives and reducing healthcare costs, has encouraged the development of broader platforms using additional optical wavelengths. Incorporating 3 or more independently controlled wavelengths has been shown to enable the real-time monitoring of multiple health factors while further reducing readout errors ? thus saving more lives. Beyond blood oxygen monitoring, a real-time noninvasive assessment of renal and hepatic health can be realized by integrating several wavelengths in the same clinically accepted pulse oximetry paradigm. Though multispectral pulse oximetry systems incorporating several optical sources have been successfully demonstrated by physicians and industry leaders, incorporating multiple LEDs (made from dissimilar semiconductors) has led to costly reliability errors and even product recalls. If successful the proposed mobile, multiwavelength single-die approach surmounts these limitations by providing independent control of several wavelengths from a single, self-aligned, compact LED. Integrating these advanced, cost-effective optical sources into traditional pulse oximetry opens up new markets in noninvasive metabolic monitoring for clinical research, paramedics, physical therapists, drug discovery, consumer eHealth markets, and home healthcare. As a spectroscopic source, other applications include air-quality/pollution monitoring and agricultural/industrial controls.
The consumer market for wearable health and fitness monitors is growing at an exponential pace, led mostly by activity trackers. But as activity trackers are maturing, consumers are demanding more than mere step counting -- consumers are increasingly demanding meaningful, actionable insight into their health and fitness. Such insight requires accurate monitoring of multiple biometric parameters, such as heart rate, respiration rate, blood oxygen levels (SpO2), blood pressure, and VO2max. However, a biometric sensor technology that can accurately measure everything that is important from a single, wearable, popular consumer form-factor has not been available in the marketplace. What is required is a highly integrated, low-power, multi-parameter sensor technology that can be easily integrated into armbands, wristbands, earpieces, and other commonly accepted consumer form-factors. The fundamental goal of this Phase II/IIB program was to address this growing demand by validating a compact multiwavelength emitter (MWLE) design that could be commercialized for biometric sensor applications. This goal was achieved through the demonstration of blood oxygen (SpO2) monitoring via a MWLE module embedded within an audio earbud. Moreover, additional benefits of this program included: 1) the education of undergraduate and graduate students in cutting-edge noninvasive biomedical sensor technology, 2) the generation of new human physiology knowledge of the ear anatomy, 3) the publication of several papers, and 4) the development of ongoing synergies with separate R&D efforts. Ultimately, this MWLE solution will help satisfy several imminent public needs: 1) the clinical need for an all-in-one comfortable, wearable vital status monitor for disease prevention and health management, 2) the academic need for a portable, automated all-in-one physiological data collection tool, and 3) the consumer demand for an engaging, mobile health (mHealth) solution for managing health throughout daily life activities.
