Raman Spectroscopy characterisation of 5C potency of homoeopathic drugs Nux vomica, Thuja occidentalis and Nitricum acidum

Background: The physicochemical characterisation of homoeopathic medicines remains a challenge. Raman spectroscopy is a promising tool for identifying structural modifications in the solvent matrix and specific vibrational ``fingerprints'' induced by the potentisation process. Objective: This study aimed to characterise three remedies (Nux vomica, Thuja occidentalis, and Nitricum acidum - 5C potencies) using Raman spectroscopy to identify specific vibrational markers and evaluate the technique's ability to differentiate between different preparations within a complex matrix. Materials and methods: The drugs were analysed as crushed granules (solid state) and after dissolution in betamethasone disodium phosphate (liquid state). Raman spectroscopy was chosen for its high specificity and minimal water interference. Samples were standardised for particle size and pressure to ensure reproducibility, comparing results against pure excipient baselines (sucrose and lactose). Results: Analysis of the granules confirmed dominant peaks of the carbohydrate matrix (1063, 1127, 1450, and 2900 cm-1). In the liquid phase, however, the three preparations exhibited unique vibrational signatures and significant spectral shifts. These differences, validated by statistical analysis of the signal-to-noise ratio, persist even at 5C potency levels, suggesting a stable interaction between the diluted component and the molecular probe. Conclusion: Raman spectroscopy provides valuable insights into the characteristic vibrational modes and functional-group interactions in homoeopathic medicines.