A new study published in ACS Sensors details the development of an ultrasensitive nanoscale sensor designed for detecting isoprene gas, a compound in breath that can indicate the presence of lung cancer. This research represents a potential breakthrough in noninvasive lung cancer screening.
Study: Ultrasensitive In2O3-Based Nanoflakes for Lung Cancer Diagnosis and the Sensing Mechanism Investigated by Operando Spectroscopy. Image Credit: New Africa/Shutterstock.com
Background
Lung cancer remains one of the most lethal cancers globally, making early detection critical. Unfortunately, traditional diagnostic methods often involve invasive procedures that can be uncomfortable and carry certain risks. However, new breakthroughs in sensor technology are opening doors to non-invasive testing—particularly through the analysis of exhaled breath.
Our breath carries a mixture of gases and compounds that reflect what is happening in our bodies. One of these compounds, isoprene, has shown promise as a lung cancer biomarker, as studies reveal that lung cancer patients often have reduced isoprene levels in their breath. This makes isoprene a key target for detection, but it is challenging to accurately measure because it is present in extremely low concentrations, typically parts-per-billion.
Previous generations of sensors, mostly metal oxide-based, have not been sensitive or selective enough to reliably detect isoprene for lung cancer screening. This new research aims to overcome that limitation by enhancing indium oxide-based sensors, making them better equipped to pick up isoprene, even with many other compounds also present in exhaled breath.
Research Overview
In an effort to advance non-invasive methods for early lung cancer detection, researchers have developed a novel series of nanoscale sensors specifically designed to detect isoprene, a biomarker found in exhaled breath. These sensors, based on indium(III) oxide (In2O3) nanoflakes, represent a significant step forward in gas-sensing technology, with the potential to transform how lung cancer is screened.
This study explored various sensor configurations to enhance both sensitivity and specificity for isoprene detection, a challenging task given the compound’s low concentration in breath. One standout design, known as Pt@InNiOx, combines platinum (Pt), indium (In), and nickel (Ni) to optimize the sensor’s catalytic properties, making it highly effective even at trace levels.
Through a series of experiments, the research team evaluated the sensors’ performance in real-time, using operando spectroscopy to closely examine their electrochemical and structural features. They also simulated real-world conditions by testing the sensors in environments with humidity levels similar to human breath, confirming the reliability of these sensors for practical applications.
Results and Discussion
The experiments demonstrated that the Pt@InNiOx sensors were capable of detecting isoprene at concentrations as low as 2 parts per billion, a sensitivity level that surpasses existing sensor technologies. Notably, these sensors showed a strong preference for isoprene over other volatile compounds typically found in breath, which is essential for accurate diagnostics. The sensors also maintained consistent performance across nine simulated tests, highlighting their reliability and suitability for clinical use.
A key factor in this exceptional performance was the structure of the nanoflakes. The platinum nanoclusters on the nanoflakes played a crucial role in catalyzing the detection of isoprene, resulting in the sensors’ ultrasensitive response. This finding emphasizes how both material composition and structural design contribute to advancements in sensor technology, potentially guiding future innovations.
To illustrate the practical application, the researchers integrated the Pt@InNiOx nanoflakes into a portable sensing device. This device was tested on breath samples from 13 individuals, including five diagnosed with lung cancer. The device successfully detected isoprene levels below 40 parts per billion in samples from cancer patients, while levels in cancer-free participants typically exceeded 60 parts per billion. These results suggest that this sensing technology could serve as an effective, non-invasive tool for lung cancer screening, providing a promising alternative to traditional, invasive diagnostic methods.
Conclusion
This new nanoscale sensor technology could be a game-changer for lung cancer screening. By using indium oxide-based nanoflakes, the researchers have developed a highly sensitive sensor that can detect tiny changes in breath chemistry linked to lung cancer. This non-invasive approach not only makes early detection easier but also means a more comfortable experience for patients.
In the future, these sensors could be built into portable devices, making lung cancer screening more accessible and potentially life-saving. This study highlights how ongoing advances in sensor technology can directly impact healthcare, bringing us closer to early, effective, and less invasive cancer detection.
Journal Reference
Cheng Y., Portela R., et al. (2024). Ultrasensitive In2O3-Based Nanoflakes for Lung Cancer Diagnosis and the Sensing Mechanism Investigated by Operando Spectroscopy. ACS Sensors. DOI: 10.1021/acssensors.4c01298, https://pubs.acs.org/doi/10.1021/acssensors.4c01298