Rapid detection of ibuprofen in water using wavelet-based hyperspectral imaging

Detecting and quantifying ibuprofen in water bodies is crucial for understanding its environmental impact. This study employs hyperspectral imaging (HSI) in the visible, near-infrared, and short-wave infrared ranges to identify ibuprofen in various liquid matrices. Partial Least Squares Discriminant Analysis (PLS-DA) was utilized to analyze optical diffuse reflectance measurements of ibuprofen dissolved in different water types (tap and river water) and ethanol samples. The analysis was performed both on preprocessed individual spectra and on components extracted using wavelet transform. The PLS-DA model demonstrated effectiveness in detecting various commercial ibuprofen formulations across these diverse water types and ethanol, and showed robustness against interference from another pharmaceutical. Notably, wavelet transform analysis in the short-wave infrared region enabled the detection of ibuprofen at 60 μg/L, with 100 % sensitivity and 100 % specificity. This concentration falls within the range of Predicted No-Effect Concentrations (PNECs) reported for ibuprofen in aquatic environments, underscores the method's potential for environmental monitoring. HSI, coupled with wavelet transform, offers a rapid, non-contact, and pre-treatment-free tool for the environmental monitoring of ibuprofen in water.