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The accurate, continuous analysis of healthcare-relevant gases such as nitrogen oxides (NOx) in a humid environment remains elusive for low-cost, stretchable gas sensing devices. This study presents the design and demonstration of a moisture-resistant, stretchable NOx gas sensor based on laser-induced graphene (LIG). Sandwiched between a soft elastomeric substrate and a moisture-resistant semipermeable encapsulant, the LIG sensing and electrode layer is first optimized by tuning laser processing parameters such as power, image density, and defocus distance. The gas sensor, using a needlelike LIG prepared with optimal laser processing parameters, exhibits a large response of 4.18‰ ppm−1 to NO and 6.66‰ ppm−1 to NO2, an ultralow detection limit of 8.3 ppb to NO and 4.0 ppb to NO2, fast response/recovery, and excellent selectivity. The design of a stretchable serpentine structure in the LIG electrode and strain isolation from the stiff island allows the gas sensor to be stretched by 30%. Combined with a moisture-resistant property against a relative humidity of 90%, the reported gas sensor has further been demonstrated to monitor the personal local environment during different times of the day and analyze human breath samples to classify patients with respiratory diseases from healthy volunteers. Moisture-resistant, stretchable NOx gas sensors can expand the capability of wearable devices to detect biomarkers from humans and exposed environments for early disease diagnostics. [ABSTRACT FROM AUTHOR]

Early Parkinson's disease (PD) may cause respiratory dysfunction; however the findings vary among studies. The aim of the preliminary prospective observational study was to explore the deterioration of pulmonary function at various stages in patients with early PD. A total of 237 patients with PD were screened. Fifty-six patients were included (modified Hoehn and Yahr stage ≤ 2.5). In addition, 56 age-matched healthy controls were also included in the study. Significant differences between the PD and control groups were found in all the investigated lung-function parameters. The maximal voluntary ventilation (MVV) percent predicted was the only parameter that distinguished PD stages (101.1 ± 14.9% vs. 82.8 ± 19.2% vs. 71.4 ± 12.9%, Hoehn and Yahr stages 1.5 vs. 2 vs. 2.5, respectively; p < 0.005). MVV could be the most sensitive parameter for distinguishing the severity of early-stage PD. [ABSTRACT FROM AUTHOR]