The idea that exhaled breath is a source of cancer biomarkers is not new, but this paper expounds a simplified approach that does not need a breath sample to be concentrated or analysed using expensive techniques. The authors analysed a series of alveolar breath samples taken from 56 age-matched healthy volunteers and 40 newly diagnosed, untreated patients with stage 3 or stage 4 lung cancer. All patients were non-smokers at the time of analysis. The authors designed an array of nine cross-reactive chemiresistors consisting of 5 nm gold nanoparticles coated with different organic compounds. These compounds were widely responsive to volatile organic compounds that had previously been identified in the breath of patients with lung cancer. These sensors could clearly distinguish alveolar breath samples from patients with lung cancer from those of healthy volunteers, without the need to dehumidify the breath or concentrate it, as has been required with previous techniques. Importantly, it seems as if these sensors are also unaffected by differences in gender, age or smoking history.
The authors verified and refined the effectiveness of the sensors by exposing them to simulated breath samples based on the four volatile organic compounds that varied most between the healthy volunteers and the patients with lung cancer. These experiments indicated an accuracy of >86% and a reproducibility of >90%.
This is a preview of subscription content, access via your institution
