چکیده انگلیسی مقاله |
An integrated design of a paper-based colorimetric sensor array (including indicators and the sample injection zone) is described. To overcome pervious limitation in volatile measurements by sensor array [1], a miniaturized chamber was designed to reduce the consumption volume, and made the work simple and affordable. In this regard, a 3D printer was used to design the 3×3 cm reaction chamber. Moreover, using the watercolor paper and placing the injection site on the surface of the paper are considered to reach these aims. The considered miniaturized chamber and analyte embedded location caused using the lowervolume of analyte (13μL) to create a vapor saturated environment. To show the applicability of the proposed sensor, a colorimetric sensor array was used for discrimination of volatile organic compounds (VOCs) related to different solvent families. The integrated colorimetric sensor (ICS) designed by spotting 12 sensing elements from three different groups (solvatochromic dyes, pH indicators and metallochromic dyes) with various properties and interactions. The color difference map (CDM) of the sensor array was obtained before and after exposure to VOCs, which was used as a fingerprint to discriminate VOC samples based on their functional group. The proposed device and sensor could discriminate 30 volatile organic compounds with linear discrimination analysis (LDA) method. They were classified in six chemical families including alcohols, amines, acids, ketones, aldehydes, nonpolar with 99% accuracy. In total, the designed device is portable, rapid, cost-effective and requires low volumes of sample that can be considered as a good candidate for various VOC analysis. |