Detection Experiment of Six Vitamins by Laser-Induced Fluorescence Spectra

Abstract

Laser-induced fluorescence (LIF) is a potential technology for the rapid, sensitive, and selective detection of vitamins. In this study, the LIF spectra (LIFS) of vitamins A, B1, C, D, E, and K1, and their mixtures were investigated under a 266-nm laser excitation via an Nd:YAG laser. The experimental results showed that the LIFS of each vitamin solution had its unique profile. The six vitamins can be distinguished to some extent by the characteristic wavelength region: 320–380 nm for vitamins A and C, 350–440 nm for vitamins D and E, and 400–470 nm for vitamins B1 and K1. Additionally, it can be used for accurate diagnosis by characteristics of LIFS (starting wavelength, spectral range, peak wavelength, maximum intensity, and extinction coefficient) as a complement. Moreover, the features of LIFS can reflect the main vitamin components in the mixture of vitamins to a certain extent when several vitamins coexist. It was found that the spectral range, maximum intensity, and extinction coefficient could report the benzene ring number, double bonds, and OH group in molecules of components in mixtures, which is a discrimination-assisted method for vitamins in a mixture. This paper also proposes a technique to identify individual components in mixtures quantitatively by using LIFS and LIFS parameters. The present study will offer technical support in clinical diagnosis and targeted therapy using vitamins via experimental exploration on detection.