It seems like these days, smartphones are getting jam-packed with more sensors and more features than ever before. When it comes to health, some of these sensors have the potential to turn your phone into a medical tricorder right out of Star Trek.
Why would you need biosensors in your smartphone? There are a lot of reasons. Whether you have a specific medical condition that requires constant monitoring, or you’re just a fitness enthusiast who wants to log your most important body metrics, there are biosensors due to hit the smartphone market soon that’ll make you very happy.
Blood Oxygen Monitoring
Monitoring your heart rate or your body temperature are standard on many wearables like the Fitbit (Amazon) or the Jawbone (Amazon), but what if you could do the same thing and more with your smartphone?
Enter Project Ara, a healthcare project launched by none other than Google (believe it or not), which promises to monitor the oxygen levels in your blood with a simple touch of your finger on a special sensor.
The blood oxygen sensor, called a pulse oximeter, is actually mounted on a single module that makes up only one of the many modules included in Project Ara. The project is actually one of a “modular” smartphone where you can basically mix and match the modules that you want. It’s basically a custom-built smartphone where you can add all of the sensors that are important to you.
The pulse oximeter sensor shines red light and infrared light directly into your skin, and the ratio of infrared light to red light that gets absorbed (and not returned to the sensor) allows the module to determine how much oxygen there is in your blood. This is because the infrared light is actually absorbed by the hemoglobin (a protein in red blood cells), and the amount of oxygen present affects infrared absorption.
If you’ve ever been to the emergency room and you’ve had one of those weird devices clipped onto your finger, then you’ve already had this technology used on you!
Why would knowing the oxygen saturation of your blood be important? There are a lot of things that can cause low blood oxygen level, including:
- Lung disease or lung injury
- Pulmonary embolism (blood clot in the artery)
- Congestive heart failure
Any disease or illness that results in reduced gas exchange in the lungs can significantly hurt blood oxygen levels, and it can be an important warning sign for major health problems later on.
While Google’s modular phone idea is pretty cool, the blood oxygen sensor isn’t new. In fact, many phones – like the Samsung Galaxy Note 4 – come with the technology built right into it. Like similar Samsung devices, it comes preloaded with an app called S Health, which has a component called SpO2 for measuring your blood oxygen levels.
You just place your fingertip over the sensor, and within about 10 to 15 seconds you’ll have your reading.
Samsung beat Apple to the technology – however Apple has built the technology into its new Apple iWatch product.
Any Star Trek fan will remember scenes where an “away team” would beam down to a planet’s surface, and start scanning the environment for signs of life.
Wouldn’t be cool if your phone could scan the environment in the same way? Well, if researchers at the University of Illinois have their say, this will be a possibility in the near future. In 2013, researchers there developed a wedge-shaped cradle for the iPhone, filled with various lenses and filters that allow the iPhone’s optical sensors to detect biological agents in the environment including molecules, viruses and toxins (basically, a spectrometer).
According to the University of Illinois press release, the technology offers measurements as accurate as a $50,000 spectrophotometer, but contains only $200 worth of optical equipment. The researchers say that the potential uses for this technology are exciting.
“Having such sensitive biosensing capabilities in the field could enable on-the-spot tracking of groundwater contamination, combine the phone’s GPS data with biosensing data to map the spread of pathogens, or provide immediate and inexpensive medical diagnostic tests in field clinics or contaminant checks in the food processing and distribution chain.”
The cradle uses a photonic crystal that uses changes in wavelengths of light passing through it as various biological agents attach to it, to analyze the makeup of those agents. The crystal can analyze cells, pathogens, and even the DNA of biological matter. The cradle works like a microscope, where the user affixes the biological matter to the photonic crystal slide, and then inserts the slide into the cradle for analysis by the app.
The researchers demonstrated the cradle in a YouTube video.
The app essentially looks for a gap in the wavelight spectrum to determine the makeup of biological matter being analyzed. Such an affordable technology may transform how aid workers around the world provide health services and environmental analysis to communities where that technology could save lives.
This is similar to the spectral analysis sensor technology developed by Argonne National Laboratory in 2006 to analyze and detect the presence of chemical, biological and nuclear materials, intended for use in “national security applications”. The University of Illinois application brings this kind of impressive environmental analysis technology to the everyday user, in an affordable package.
There are already startups jumping on the bandwagon, with Fringoe, a Singapore company, taking pre-orders for its spectrometer for iOS devices, and a molecular spectrometer called SCIO that’ll let you analyze the calories in your food in seconds. More devices are surely going to capitalize on technology, and smartphone manufacturers may even integrate it directly into phones.
Health Monitoring on Steroids
Most smartphones these days have the ability to monitor a person’s heart rate or their blood oxygen levels (as described above), but what if your smartphone could continuously monitor things like the electrical signals from your heart (electrocardiogram), or blood glucose levels?
In 2012, researchers from Wilfrid Laurier University did exactly that, piloting a “continuous multi-sensor monitoring system of real-world physiological conditions and daily life) using just a smartphone and applicable, wearable sensors.” The report was published in the journal Telemedicine and e-Health.
Principle researcher Sean Doherty partnered with the Toronto Rahabilitation Institute to set up 40 diabetes patients with blood glucose monitoring devices that would monitor the patients and collect data for 72 hours. What made the pilot project so unique is that the sensor didn’t require the patient to prick their finger for blood, it communicated directly with the patient’s smartphone, and it used GPS to try and correlate location information with blood glucose data.
The pilot study proved that such a setup worked, and provided accurate, useful information about the patient’s health.
“All but three subjects were successfully monitored for the full study period. Smartphones proved to be an effective hub for managing multiple streams of data but required attention to data compression and battery consumption issues. ECG, accelerometer, and blood glucose devices performed adequately as long as subjects wore them.”
Considering that there are over 25 million children and adults in the U.S. with diabetes, the potential for such a non-invasive sensor and monitoring system is an industry in itself.
The technology to monitor blood glucose non-invasively is here, but with questionable accuracy. One company called Glucowise sells a non-invasive sensor that can determine blood glucose concentration at the capillary level. It uses low-power, high-frequency radio waves around the 65 GHz range to penetrate thin areas of skin (like that between thumb and forefinger or the earlobe) and measure the blood characteristics.
It’s yet to be seen how effective this approach is. Non-invasive techniques for blood glucose monitoring have been attempted many times in the past and they fail – such as the HG1-c device developed by C8 MediSensors, a company that Apple approached about potentially integrating the tech with the Apple iWatch. It didn’t take long for Apple to realize that the technology wasn’t conducive to a wearable device for many reasons:
- It required complete darkness to pick up on what former C8 employee Charles martin called “faint signal emitted by the glucose molecules.”
- It required a large battery pack, with energy demands too large for the Apple iWatch.
- Users would need to apply a gel to the skin for a more accurate reading.
The challenges are daunting, but that isn’t stopping countless startups from stepping up to the challenge, such as Infra, a wearable wrist-monitor that provides blood sugar, blood pressure, pulse, oxygen levels and more, non-invasively. The product Indiegogo campaign ended on October 21st of 2014, reaching $12,861 above its goal of $50,000 in funding. The company website still doesn’t offer the product for sale, with a “Watch for our launch” still displayed in the News section.
New Sensors Open New Possibilities
All of these sensors, if they are successfully integrated into existing smartphone or smart watch products, promise to transform lives.
Imagine never having to prick your finger again to obtain your blood glucose levels. Imagine receiving a complete report of all of your vital signs – blood oxygen, blood pressure and EKG readings – all right on your smartphone screen after you’re done working out. Imagine simply pressing a button and getting a full listing of the air quality in your home, complete with a list of air contaminants that could be harmful to your family’s health.
The possibilities are endless, and the only thing holding it back is really just the development of practical sensors themselves. Many of them are very close to viable, and others are already available and only need to be integrated into new smartphone platforms.
What new sensors would you love to see on your future smartphone? Are there any interesting uses you can imagine for the sensors listed above? Share your thoughts in the comments section below!