A colorimetric detector for lung cancer related volatile organic compounds based on cross-response mechanism

In this paper, a detection device for lung cancer related Volatile Organic Compounds (VOCs) was constructed. A sensor array based on a cross-responsive mechanism, using Porphyrin and its derivates, was designed. A new uniformly-illuminative light source was made to insure the RGB signals accurately and stably acquired by CMOS camera. And Trace-pro software was used to simulate the performance of the light source. The data collection and processing system was used to detect color changes of the sensor arrays before and after reaction, which extract unique patterns of the tested VOCs. Four selected VOCs, p-xylene, styrene, isoprene and hexanal, were detected by the proposed device. Unsupervised pattern recognition methods, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were used to analyze the data. The results showed that the methods could 100% discriminate the four VOCs and the device obtained responses at concentrations varying from 50 ppb to 500 ppb. In conclusion, the proposed detection device showed excellent selectivity and discrimination ability for the VOCs related to lung cancer. Furthermore, our preliminary study demonstrated that the proposed detection device has brilliant potential application for early clinical diagnosis of lung cancer.