Abstract
Ambient ionization mass spectrometry (AIMS) has emerged as a transformative analytical technology in pharmaceutical analysis, enabling rapid, direct, and minimally invasive analysis of complex samples under ambient conditions. Unlike traditional analytical techniques that require extensive sample preparation and chromatographic separation, AIMS facilitates real-time detection of pharmaceutical compounds, impurities, and metabolites directly from surfaces or bulk matrices. This review critically explores the principles, instrumentation, and applications of ambient ionization techniques such as desorption electrospray ionization (DESI), direct analysis in real time (DART), and paper spray ionization (PSI) in pharmaceutical sciences. Emphasis is placed on their role in rapid drug screening, counterfeit drug detection, quality control, and impurity profiling. The integration of AIMS with high-resolution mass spectrometry has further enhanced analytical sensitivity and specificity, enabling trace-level detection in complex matrices. Despite its advantages, challenges such as matrix effects, reproducibility, and regulatory acceptance remain significant barriers to widespread adoption. This review also discusses recent advancements, including automation and coupling with artificial intelligence, to overcome these limitations. Overall, AIMS represents a promising frontier in pharmaceutical analysis, offering rapid, cost-effective, and versatile analytical solutions for modern drug development and quality assurance.