Development and evaluation of a Raman detector for non-destructive identification and quantitation of cytostatic...

Personalized chemotherapy requires precise compounding and reliable quality control to assure therapeutic efficacy and safety. Raman spectroscopy offers a non-destructive and non-invasive method for the identification and quantitation of cytostatic drug substances, which could improve current quality assurance processes in hospital or community pharmacies. In this study, a dedicated Raman detector was developed that enables direct identification and measurement of cytostatic drug concentrations in aqueous liquids through closed primary packaging. Measurements were performed for cyclophosphamide and gemcitabine in clinically relevant concentrations (1 - 45 mg mL^-1) using sealed infusion glass vials, filled syringes for bolus injections and infusion bags. Each concentration was analyzed at eight different positions. These measurement positions were chosen randomly to account for signal variability arising from local material variations, including inhomogeneities in wall thickness and curvature. For all tested drug substances and packaging types and materials, relative prediction errors remained within ±10% across the clinically relevant concentration range, with a RMSECV of 1.07 mg mL⁻¹ for cyclophosphamide and 0.54 mg mL⁻¹ for gemcitabine. As routine quality control of individually compounded antineoplastic formulations lacks standardized final-product verification, non-invasive through-container spectroscopic analysis offers the possibility to add identity and concentration confirmation without opening or sampling the CMR-classified formulation. This method preserves the integrity of the final drug product while reducing costs and the risk of occupational exposure for pharmacy personnel.