An optical fiber sensor based on a B10H14 derivatives/PMMA film for measuring low concentration formaldehyde in aqueous solutions

Abstract

The concentration of formaldehyde in the environment must be precisely monitored, as it is closely linked to human health. In this paper, a decaboryl derivative formaldehyde fluorescent probe (M1) was synthesized for the first time by introducing a 5-amino-isoquinoline group into a decaborane parent. Using theoretical calculations, ¹H-NMR, ¹¹B-NMR, HR-MS, and FT-IR, the molecular structure of the probe was determined and its response mechanism to formaldehyde was examined. The fluorescence response of the probe to formaldehyde was then tested, revealing an augmented response to formaldehyde in a solution of 0–600 μM, with a detection limit of 4.18 × 10⁻⁶ M. The results show that the formaldehyde fluorescence probe has the advantages of good linearity, strong anti-interference and high sensitivity. On this basis, a fiber optic formaldehyde fluorescence sensor based on an M1/PMMA thin film was constructed in this paper. This fiber optic fluorescence sensor, with its high selectivity, low detection limit, online and remote monitoring, and other advantages, was successfully applied to the detection of formaldehyde in both food and aqueous solutions, with results that were reliable compared to those of acetone. The detection limit of formaldehyde increased to 6.9 × 10⁻⁸ M. The potential for its utilization in the chemical, biological, environmental, and other formaldehyde detection fields is quite promising.