Development of a colorimetric sensor Array for the discrimination of aldehydes

A brand-new colorimetric sensor array was developed based on cross-reactive mechanism to discriminate 9 kinds of aldehydes and 16 volatile organic lung cancer biomarker candidates in low concentration. Sixteen out of twenty-seven dyes were selected to mix with 2,4-dinitrophenylhydrazine (DNPH) in optimized concentration to serve as specific sensing elements, and polyethylene glycol-1000 was chosen from four kinds polyethylene glycols to act as stabilizer. Resultant sensor array shows improved response (about tenfold higher) to aldehydes than former study, and exhibited very good selectivity in low concentration ranging from 40 ppb to 10 ppm with the presence of interfering counterparts. Data analysis was performed by both hierarchical cluster analysis (HCA) and discriminant analysis (DA), which demonstrates the excellent discrimination ability of the sensor to structurally similar aldehydes related to lung cancer. Besides, formaldehyde-spiked air samples were analyzed with developed sensor array, suggesting promising utilization potentiality to monitor such toxic gas. Theoretical detection limit was down to 8.2 ppb with a liner range from 10 ppb to 150 ppm. The sensor array can be further developed for early diagnosis of lung cancer as well as monitoring of domestic and industrial formaldehyde pollution.