Mapping active pharmaceutical ingredients distributions in tablets using time-of-flight secondary ion mass spectrometry with multivariate curve resolution

[Display omitted] •ToF-SIMS in combination with MCR mapped the 3D distribution of APIs.•Indapamide, amlodipine, and perindopril showed distinct spatial distribution.•Unique ion peaks for APIs allowed exact differentiation in ToF-SIMS imaging.•MCR processing revealed micro-scale API agglomerates, influencing tablet uniformity. This study introduces an advanced approach to identifying signals associated with indapamide, amlodipine, and perindopril in solid dosage form using time-of-flight secondary ion mass spectrometry (ToF-SIMS) combined with multivariate curve resolution (MCR). The primary objective was to obtain and characterize these signals through MCR factors, which then led to identifying unique signals specific to each active pharmaceutical ingredient (API). These unique signals were crucial for constructing detailed 2D and 3D images of the API distribution within the tablet. The results demonstrated that indapamide and amlodipine exhibited multiple unique peaks, while perindopril had only one. Additionally, the study revealed non-homogeneous distribution patterns of APIs and excipients, such as SiO2 and Mg stearate. This work highlights the significance of applying advanced analytical techniques such as ToF-SIMS and MCR in the pharmaceutical field to ensure consistent therapeutic efficacy through a better understanding of API distribution.