A team of researchers from the American Chemical Society in the United States has developed ultrasensitive nanoscale sensors that, in small-scale tests, managed to detect a significant change in the breathing chemistry of people with Alzheimer’s disease. lung cancer. The research, published in the journal ACS Sensors and led by Pingwei Liu and Qingyue Wang focused on designing sensors based on indium oxide nanosheets.
People exhale various compounds, such as water vapor, carbon dioxide, and other volatile chemicals. In this study, researchers identified that the decrease in isoprene, an expired chemical compound, could be an early indication of lung cancer. However, to be able to detect such small variations, the sensors must be extremely sensitive, capable of identifying isoprene levels in the parts per billion (ppb) range.
The researchers note that this technology could represent a significant advance in non-invasive detection of lung cancer, enabling earlier diagnoses and better survival rates.
lung cancer It is a tumor that forms in the tissues of the lung, usually in the cells that line the airways. It is the leading cause of cancer death in both men and women.
There are two main types: small cell lung cancer and non-small cell lung cancer. These two types grow differently and are treated differently. Non-small cell lung cancer is the most common type.
Additionally, the sensors must be able to distinguish isoprene from others volatile compounds present in respiration and resist the natural humidity of respiration. Although previous attempts to create gas sensors with these characteristics relied on metal oxides, indium oxide was a particularly promising compound. The team led by Liu and Wang set out to optimize these indium oxide-based sensors to detect isoprene at concentrations found in human breath.
During their experiments, the researchers discovered that a type of sensor, which they called Pt@InNiOx after the elements of platinum (Pt), indium (In) and nickel (Ni) which containedshowed the best performance. These sensors were capable of detecting isoprene levels as low as 2 ppb, far exceeding the sensitivity of previous sensors. Additionally, they responded to isoprene more accurately than to other common volatile compounds found in human breath.
During nine simulated use cycles, the analysis showed that the sensors maintain their effectiveness. Detailed analysis of the structure and electrochemical properties of the nanosheets revealed that platinum nanoclusters uniformly anchored on them helped trigger the detection of isoprene, thereby improving the sensitivity of the sensor.
To validate the medical applicability of this technology, researchers integrated the Pt@InNiOx nanosheets into a wearable sensing device. This device was tested with the breath of 13 people, five of whom had been diagnosed with lung cancer. The results showed that the levels detected by the device of isoprene less than 40 ppb in participants with cancer and greater than 60 ppb in those without the disease.
