Quantification of febuxostat polymorphs using powder X-ray diffraction technique

Febuxostat is a drug with multiple polymorphic forms, and form A is most commonly used. It often exists in mixtures with form G. Understanding the proportions of these forms is important for drug quality and performance. Prior research has shown that polymorphs can affect drug solubility and stability. However, quantifying these forms remains a challenge. No prior work had resolved a precise and sensitive method for this task. This gap motivated the development of a new analytical approach. Existing methods lack the precision needed for low concentrations. The need for a reliable quantification method is clear. This study addresses that need using powder X-ray diffraction. The method aims to improve accuracy and repeatability in polymorph quantification.

The goal of this work is to develop a reliable method for quantifying febuxostat polymorphs A and G. The study focuses on creating a precise and sensitive analytical technique. The researchers aim to use powder X-ray diffraction for this purpose. They want to ensure the method is repeatable and accurate. The study also seeks to validate the method for practical use. The need for a validated method is driven by drug development requirements. The researchers aim to provide a tool for quality control in pharmaceutical production. The ultimate goal is to support drug formulation and stability studies.

The method uses powder X-ray diffraction to quantify febuxostat polymorphs. Pure forms A and G were first characterized for baseline data. A continuous scan at 3° min(-1) was used over 3-40° 2θ. Characteristic peaks at 12.78° and 11.72° 2θ were selected for analysis. The calibration curve was built using peak areas from these angles. Linear regression analysis was applied to determine the relationship. The concentration range tested was 10-60 wt.%. The method was validated for precision, recovery, and ruggedness.

The calibration curve showed a strong linear relationship with R(2)=0.9985. The peak areas for forms A and G were measured accurately. The method was validated for precision and recovery. The detection limit was 1.5%, and the quantitation limit was 4.6%. These values indicate high sensitivity and accuracy. The method proved repeatable across multiple trials. The results suggest it is suitable for real-world applications. The proposed method can be used for mixtures of forms A and G.

The developed PXRD method is repeatable, sensitive, and accurate. It provides a reliable way to quantify febuxostat polymorphs A and G. The results support its use in pharmaceutical quality control. The method is validated for practical application. The detection and quantitation limits are suitable for most mixtures. The linear relationship confirms the method's reliability. The authors suggest it can be used for drug development and stability studies. The method addresses a gap in polymorph quantification techniques.