ICH Q14-inspired novel approach to establish an SFC-based purity method for carbamazepine

The proposed ICH Q14 guideline "Analytical procedure development" describes science and risk-based approaches for development and maintenance of analytical procedures suitable for the assessment of the quality of drug substances and drug products. As a case study, the systematic development and validation of a supercritical fluid chromatography (SFC)-based purity method for carbamazepine is presented. Systematic analytical quality by design (AQbD) principles were applied using the software package Fusion QbD to the method development approach. The relationship between chromatographic parameters and the responses of interest were examined to improve the reliability of the method by understanding, reducing, and controlling sources of variability. Method performance qualification in terms of method robustness was finally carried out with the parameters that were classified as critical after method development and a validation study met previously set acceptance criteria. The developed SFC purity method for carbamazepine demonstrated readiness as a viable alternative to the official HPLC method published in the Ph.Eur. with improved peak resolution, improved peak symmetry, and faster analysis times (3 min vs. 80 min for the official method). Its inherent reliability illustrates the superiority of AQbD in method development and application for drug quality assurance.

Quantitative mass spectrometry methods for pharmaceutical analysis

Quantitative pharmaceutical analysis is nowadays frequently executed using mass spectrometry. Electrospray ionization coupled to a (hybrid) triple quadrupole mass spectrometer is generally used in combination with solid-phase extraction and liquid chromatography. Furthermore, isotopically labelled standards are often used to correct for ion suppression. The challenges in producing sensitive but reliable quantitative data depend on the instrumentation, sample preparation and hyphenated techniques. In this contribution, different approaches to enhance the ionization efficiencies using modified source geometries and improved ion guidance are provided. Furthermore, possibilities to minimize, assess and correct for matrix interferences caused by co-eluting substances are described. With the focus on pharmaceuticals in the environment and bioanalysis, different separation techniques, trends in liquid chromatography and sample preparation methods to minimize matrix effects and increase sensitivity are discussed. Although highly sensitive methods are generally aimed for to provide automated multi-residue analysis, (less sensitive) miniaturized set-ups have a great potential due to their ability for in-field usage.This article is part of the themed issue 'Quantitative mass spectrometry'.