Coming soon to your home: the next generation of health sensors
First there were smart pedometers that measured sleep and steps. Then came the equivalent of a Star Trek tricorder that measured heart rate, skin/core body temperature, SpO2 (oxymetry), respiratory rate, blood pressure, ECG, and emotional stress. Now we have a new generation of sensors on the horizon.
Researchers at the University of California in San Diego have developed a wearable tattoo-like sensor that continuously measures lactate levels in a user's sweat. As a marathon runner, I could find some uses for that innovation. In a clinical context, elevated lactic acid is a maker for the suboptimal supply of oxygen to the tissues and is associated with sepsis. According to the researchers:
In the present work, we demonstrate a noninvasive enzymatic temporary-transfer tattoo electrochemical biosensor for the continuous assessment of lactate levels in human perspiration. In particular, the new device aims at yielding useful insight into the temporal dynamics of sweat lactate production during controlled physical activity. The development of epidermal biosensors for lactate monitoring builds on our promising recent introduction of temporary transfer tattoo-based electrochemical sensors. These flexible tattoo sensors, fabricated via conventional screen printing methods, conform to the contours of the body and display resiliency toward extreme mechanical stresses expected from physical activity due to the presence of dispersed carbon fibers within the screen printed inks.
From Brain Activity to Hydration
MC10, a Cambridge-based wearable electronics company, is developing a sensor with the look-and-feel of a smart band-aid. The band-aid contains flexible electronic circuits and is attached to the wearer's skin using a rubber stamp. In a paper published in materialstoday, researchers described the potential for the technology within healthcare:
For skin-based and point-of-care health diagnostics, there are many applications ranging from tracking heart rate and measuring brain activity to hydration measurements from light-based assessment of bioanalytes in sweat secreted through skin pores. Skin based systems also have brought to the forefront ultrathin, flexible antenna designs and stretchable batteries to power such systems during continuous and/or intermittent use ...
Despite the necessary clinical trials being pursued to assure biocompatibility and overall safety, it is apparent from the number of clinical applications underway in cardiac, neural, and health monitoring applications that systems containing active electronics mounted on sheets and catheters will bring forth new generations of devices in many areas of healthcare over the next decade.
Biosense Technologies, a Mumbai-based company founded by an MIT engineer, this year released uCheck, which provides urinalysis via the phone. Its mobile app takes a picture of a - how should I put this - "prepared" urine test strip and provides an analysis of kidney function via bilirubin, glucose, etc. (Note: the FDA recently expressed concern about uCheck's lack of regulatory clearance.)
Coming Soon to your Home
The basic trend that we're seeing is a movement of technology to the home that was previously only available to highly-skilled professionals inside of hospitals and clinics. Clayton Christensen says it best:
In most industries, when radically new technology emerges that enables people to do things that previously were impossible, the technology is so expensive and complicated, that provision of the service must be centralized. The people and problems flow to the technology, rather than vice versa. ... In the 1960s and 1970s we brought our computing problems in the form of punched cards to the corporate or university mainframe computing center, where an expert ran the job for us. ... Modern healthcare is no different ... we collect blood and other fluid and tissue samples from dispersed doctors' offices and transport them to a central laboratory where complex, high-speed equipment performs the required analysis. ... Disruption inverts this system, so the solution is delivered to the problem.