Hyperspectral unmixing for Raman spectroscopy via physics-constrained autoencoders
Dimitar Georgiev, A. Fernandez-Galiana, Simon Vilms Pedersen, Γεώργιος Παπαδόπουλος, Ruoxiao Xie, Molly M. Stevens, Mauricio Barahona
Abstract
Raman spectroscopy is widely used across scientific domains to characterize the chemical composition of samples in a nondestructive, label-free manner. Many applications entail the unmixing of signals from mixtures of molecular species to identify the individual components present and their proportions, yet conventional methods for chemometrics often struggle with complex mixture scenarios encountered in practice. Here, we develop hyperspectral unmixing algorithms based on autoencoder neural networks, and we systematically validate them using both synthetic and experimental benchmark datasets created in-house. Our results demonstrate that unmixing autoencoders provide improved accuracy, robustness, and efficiency compared to standard unmixing methods. We also showcase the applicability of autoencoders to complex biological settings by showing improved biochemical characterization of volumetric Raman imaging data from a monocytic cell.