A robust analytical method for simultaneous quantification of 13 low-molecular-weight N-Nitrosamines in various pharmaceuticals based on solid phase extraction and liquid chromatography coupled to high-resolution mass spectrometry

Recently, the potentially highly carcinogenic N-nitrosamines (NAs) have become the focus of pharmaceutical regulatory authorities, the pharmaceutical industry and researchers because trace amounts have been detected in some drug products (DPs), resulting in drug supply shortages. In the absence of sufficient analytical methods for the determination of multiple regulated low-molecular-weight NAs in various DPs, a robust, selective, sensitive and accurate method based on sample preparation by solid-phase extraction, followed by liquid chromatography high-resolution mass spectrometry for the simultaneous analysis of 13 regulated low-molecular-weight NAs was developed. The best results for the cleanup were obtained using Strata X-C SPE cartridge. The proposed method was successfully validated according to the USP general chapter <1469>, demonstrating its excellent linearity, accuracy and precision in wide analytical ranges, adjusted to NAs acceptable intake limits. The achieved limits of quantitation correspond to 30% or less of the acceptable intake limits. The developed analytical method was applied to 16 commercially available DPs containing one to three active pharmaceutical ingredients with different physicochemical properties. Only N-Nitrosodimethylamine was detected in DPs containing ranitidine at levels exceeding the regulatory AI limits by 37.6 - 57.4-fold. In addition, the robustness of the method was confirmed on a considerable number of DPs containing different active ingredients, demonstrating the suitability of the analytical method for routine quality control of different DPs, thus mitigate the risk to human health.