title: Discrimination of fresh fruit juices by a fluorescent sensor array for carboxylic acids based on molecularly imprinted titania.
abstract: Design of chemical sensor arrays that can discriminate real-world samples has been highly attractive in recent years. Herein a fluorescent indicator-displacement sensor array for discrimination of fresh fruit juices was developed. By coupling the unique high affinity of titania to electron-donating anions and the cross-reactivity of molecularly imprinted materials to structurally similar species, a small array was fabricated using only one rhodamine-based fluorescent dye and three synthesized materials. Citric, malic, succinic and tartaric acids were chosen as indices. The recognition mechanism was investigated by spectrofluorimetric titration using a non-linear Langmuir-type adsorption model. The proposed method was applied to discriminate thirteen fruit juices through their carboxylic acid contents. Principal component analysis of the data clearly grouped the thirteen juices with the first principal component owning 98.2% of the total variation. The comparison of the sensor array with HPLC determination of the carboxylic acids was finally made.
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China.
authors.forename: Jin
authors.initials: J
authors.lastname: Tan
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China. Electronic address: ztjiang@tjcu.edu.cn.
authors.forename: Zi-Tao
authors.initials: ZT
authors.lastname: Jiang
mesh_terms: D001628:Beverages; D002264:Carboxylic Acids / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005456:Fluorescent Dyes; D005638:Fruit / Q000737:chemistry*; D054802:Molecular Imprinting / Q000379:methods*; D014025:Titanium / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D005456:Fluorescent Dyes; C009495:titanium dioxide; D014025:Titanium
keywords: Carboxylic acid; Fluorescent indicator-displacement; Fresh fruit juice; Molecular imprinting; Sensor array; Titania