Speaker
Description
Optimization of an analytical method for the determination of calcium and magnesium content using inductively coupled plasma (ICP) technique
Stojance Kirovski1,2, Aleksandra Damjanoska1,2, Cveta Dolikjoska-Trajkova1, Stefan Radevski1, Liljana Velkovska1,2
e-mail: skirovski@alkaloid.com.mk
1Alkaloid AD Skopje, Blvd. Aleksandar Makedonski 12, Skopje, Republic of N. Macedonia
2Institute of Applied Chemistry and Pharmaceutical Analysis, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Mother Tereza 47, Skopje, Republic of N. Macedonia
Lifecycle monitoring of analytical procedures described in ICH Q141 encompasses all activities from method development and validation to routine application and continual improvement. This study describes the optimization of an ICP analytical method for the determination of calcium and magnesium content during its lifecycle, based on continuous monitoring of result trends, which indicated the need for improved accuracy and robustness.
The optimization focused on critical sample preparation parameters, including filtration, calibration range, and the type of standards used. The results demonstrated that the type of filter (blue dot paper or regenerated cellulose (RC) 0.45 µm) does not significantly affect the accuracy or precision of the results, enabling the use of RC filters for routine analysis.
Extension of the calibration range improved linearity and correlation coefficients. However, discrepancies in assay values were observed when using externally sourced solution standards. This was successfully resolved by introducing in-house solid-state standards prepared from API materials, which ensured accurate recoveries (~100%) and improved agreement with expected results.
The optimized method was verified across multiple batches, placebo-spiked samples, and API combinations, demonstrating acceptable specificity, precision, accuracy, and reproducibility, including inter-analyst consistency.
Overall, this study illustrates how a lifecycle-based approach to method optimization can significantly enhance method performance and reliability. The use of in-house solid secondary standards combined with optimized sample preparation conditions ensures a robust and fit-for-purpose analytical method suitable for routine quality control.
Keywords: ICP, lifecycle management, method optimization, secondary standards, sample preparation, accuracy.
References:
1International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). ICH Harmonised Guideline Q14: Analytical Procedure Development. 2023. Available from:https://database.ich.org/sites/default/files/ICH_Q14_Guideline_2023_1116.pdf