Development of a Compact Optical Layout for a Miniature Fluorescence Spectrometer: In-Situ Detection of Organic Pollutants in Aquatic Environment

In recent years, the increasing presence of emerging organic pollutants in rivers, lakes, and other aquatic environments has posed significant threats to human health and ecological safety. Current monitoring technologies for these pollutants face several challenges, including the high cost of equipment and the scarcity of trained professionals. Furthermore, existing portable fluorescence sensors are limited by inadequate data, unsuitability for in-situ water environments, and the ability to detect only specific pollutants. This paper proposes a novel design for an in-situ miniature fluorescence spectrometer, utilizing a compact optical layout to monitor organic pollutants in water. The design features a high-power UV LED combined with a lens group to enhance the fluorescence excitation effect of low-concentration organic pollutants. The system components are integrated into a compact layout centered around a flow cell, significantly reducing the device's size. In experimental validation, vitamin B was used as a model organic pollutant to test the prototype's detection capabilities. Within the concentration range of 1 − 100 μg/L, the fluorescence intensity exhibited a strong linear correlation with the vitamin B concentration, achieving an R<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> value of 0.9945, comparable to that of commercial spectrometers. This portable device demonstrates excellent performance in detecting organic matter and offers significant advantages for in-situ monitoring applications, making it well-suited for real-time pollutant detection in rivers, lakes, and other aquatic environments.