Luminescent lanthanide metallogel as a sensor array to efficiently discriminate various saccharides

By loading 3-nitrophenylboronic acid (3-NPBA) which can react with saccharide, the fluorescence lan-thanide metallogel can emit fluorescence signals at 398, 490 and 546 nm. Thus, a three-dimensional responsive fluorescence sensor array (H6L/Tb3+/3-NPBA) was prepared to recognize saccharides. Due to the typical pH responsiveness of the fluorescence behavior of the sensor array, it is suitable for H+ gen-eration systems, such as the reaction of 3-NPBA with cis-diol of saccharides. The response of fluorescence signal intensity to 15 different saccharides was measured, and the qualitative discrimination of those sac-charides was investigated by principal component analysis (PCA). The results showed that PCA elliptic clusters did not overlap, even though the concentration of the saccharides was as low as 3 mmol/L, and the discrimination rate of each saccharide reached 100 %. The "double blind" experiment indicated that the sensor system has good ability to discriminate unknown component samples. Furthermore, the discrimination rate of fructose/glucose mixtures with varied mole ratios also reached 100 %. The method of Euclidean distance confirmed that there was a good linear correlation between PCA elliptic clusters of fructose and its concentration, which could realize the quantitative analysis of fructose. The results of PCA indicated that the elliptic clusters of tea drinks with various sugars and commercially avail-able sugar-containing drinks were loosely distributed, which further confirmed that the sensor system can effectively discriminate the saccharides under the interference of complex components.(c) 2023 Elsevier B.V. All rights reserved.