In recent years, people are turning more and more to the Internet for health information and to “self-diagnose.” With an increasing variety of medical apps available for the iPhone, iPad, Android, and other mobile platforms, self-diagnosis has become even more accessible. Unfortunately, however, checking the boxes next to a variety of symptoms and waiting for a mobile device to spew forth a litany of potential ailments lacks the sensitivity and accuracy of a human diagnostician. Further, those who are not trained in medicine may misinterpret symptoms as erroneously relevant or erroneously irrelevant, leading to misdiagnosis.
A team of researchers led by Dr. Michael McAlpine of Princeton University have developed a gold- and carbon-based biosensor that can be affixed to a tooth . The purpose of the sensor, which is made up primarily of a very strong form of carbon called graphene, is to detect sequences of DNA that are specific to pathogenic bacteria.
A new breath analyzer called the Single Breath Disease Diagnostics Breathalyzer has the capacity to check for a variety of biomarkers, or biological indicators, of disease. The breathalyzer, invented by Dr. Perena Gouma of Stony Brook University, uses a sensitive ceramic chip to detect molecules in exhaled air that are only present in the case of particular disease processes. For instance, the concentration of ammonia in the breath gives information on how much waste is in the blood, which would allow home hemodialysis patients–hemodialysis is a technique used to clean waste out of the blood in the event of insufficient kidney function–to monitor their treatments. Similarly, the chemical acetone, found in nail polish remover, is a biomarker for uncontrolled diabetes.
The challenge associated with analyzing the breath for signs of disease is that there might be only a few biomarker molecules among billions of total molecules per exhaled breath. Tiny nanowires are responsible for the chip’s sensitivity. Notes Dr. Gouma:
There can be different types of nanowires, each with a tailored arrangement of metal and oxygen atoms along their configuration, so as to capture a particular compound. For example, some nanowires might be able to capture ammonia molecules, while others capture just acetone and others just the nitric oxide. Each of these biomarkers signal a specific disease or metabolic malfunction so a distinct diagnostic breathalyzer can be designed.
Gouma envisions a future in which the device could test for infection as well, noting that the wires could be programmed to detect viruses or bacteria. While the breathalyzer isn’t yet available to the public–testing is still underway–Gouma hopes to see the device hitting the consumer market within a few years.
Source: National Science Foundation
Mason, Ohio-based AssureRx Health announced this week that it has launched a personalized medicine test for attention deficit hyperactivity disorder (ADHD). The new pharmacogenomic test — GeneSightRx ADHD — analyzes variations in three genes that influence how a patient might metabolize certain medications used to treat ADHD in children and adults.