title: Colorimetric sensor arrays based on pattern recognition for the detection of nitroaromatic molecules.
abstract: This research demonstrated that, in a colorimetric sensor array, 2,4,6-trinitrotoluene (TNT), 2,6-dinitrotoluene (2,6-DNT), 2,4-dinitrotoluene (2,4-DNT) and 4-nitrotoluene (4-MNT) were identifiable through a unique pattern in a qualitative and semi-quantitative manner. The adsorption capacity of the molecularly imprinted colloidal particles (MICs) for their corresponding templates was 0.27mmol TNT/g, 0.22mmol 2,6-DNT/g, 0.31mmol 2,4-DNT/g and 0.16mmol 4-MNT/g, respectively. Every optical sensor utilized in the arrays contained three-dimensional molecularly imprinted photonic crystal (MIPC) sensor with different imprinted templates. The intelligent materials can display different colors from green to red to 20mM corresponding nitroaromatics with varying diffraction red shifts of 84nm (TNT), 46nm (2,6-DNT), 54nm (2,4-DNT) and 35nm (4-MNT), respectively. With the assistance of principal component analysis (PCA) and rational design, the sensor array can illustrate the influence of the nitryl quantity and generate a separate response region of nitroaromatics for pattern recognition with 95.25% of variance explained in the measurements by the first three principal components (PCs). The statistical analysis endowed the cross-reactive array with better classification and identification ability and this novel detection platform provided a wider applied range among other harmful chemicals in a simple sensor array with customized functionality.
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Dong
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China. Electronic address: qiulili@bit.edu.cn.
authors.forename: Lili
authors.initials: L
authors.lastname: Qiu
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China.
authors.forename: Zequn
authors.initials: Z
authors.lastname: Yan
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China. Electronic address: m_zihui@yahoo.com.
authors.forename: Zihui
authors.initials: Z
authors.lastname: Meng
authors.affiliation: School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing, 100081, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Xue
authors.affiliation: Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, PR China.
authors.forename: Xuan
authors.initials: X
authors.lastname: He
authors.affiliation: Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, PR China.
authors.forename: Xueyong
authors.initials: X
authors.lastname: Liu
keywords: Molecular imprinting; Nitroaromatics; Pattern recognition; Photonic crystal (PhC); Principal component analysis (PCA)