When it comes to testing for environmental pollution, food contaminants and even cancer, traditional sensors can help, but the problem is they are often bulky, expensive, non-intuitive and complicated.
That may soon change as portable pressure-based detectors coupled with smartphone software could provide a simpler, more affordable alternative while still maintaining sensitivity.
Current disease and contamination sensors require expensive readout equipment or trained personnel. Yuehe Lin from the School of Mechanical and Materials Engineering, Washington State University and Yong Tang, from Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering and the Institute of Food Safety and Nutrition, Jinan University, Guangzhou, China, and colleagues propose a new detection system based on pressure changes.
The device is operated by measuring the pressure change produced by oxygen (O2) generation in a limited chamber using a portable barometer.
One case in point is when a disease biomarker is present, it causes a chain reaction in the device that results in oxygen being released and pressure building.
The pressure changes end up measured by a portable barometer, and smartphone software provides an easy readout of the results.
To show the versatility of the pressure sensor, the team tested a variety of applications.
Prototypes could detect carcinoembryonic antigen, a protein present in high levels in patients with colon or rectal cancer; ractopamine, which is an animal-feed additive banned in many countries; and thrombin, a cardiovascular disease marker.
In addition, a mercury-ion sensor was developed for environmental pollution monitoring.
Researchers said because the results are immediately available with a smartphone, the method could enable real-time monitoring of environmental pollution, disease outbreaks and food safety.