Solid-state stability and compatibility studies of clavulanate potassium

Area of Science:

• Pharmaceutical Chemistry
• Solid-State Chemistry
• Analytical Chemistry

Background:

• Clavulanate potassium is a crucial beta-lactamase inhibitor, often formulated in solid dosage forms.
• Understanding its solid-state degradation is vital for ensuring drug efficacy and shelf-life.
• Previous studies have not fully elucidated the kinetic and thermodynamic aspects of its solid-state degradation pathways.

Purpose of the Study:

• To investigate the kinetic and thermodynamic parameters governing the solid-state degradation of clavulanate potassium.
• To evaluate the compatibility of clavulanate potassium with common pharmaceutical excipients.
• To predict degradation mechanisms and reactive sites using computational chemistry and spectroscopic analysis.

Main Methods:

• Reversed-phase high-performance liquid chromatography (RP-HPLC) for kinetic analysis.
• Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) for thermal stability.
• Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and computational modeling (HOMO/LUMO) for structural and compatibility analysis.

Main Results:

• Clavulanate potassium degradation in the solid state follows first-order kinetics, significantly influenced by relative humidity (RH) and temperature.
• Kinetic models were established, showing dependencies on substrate concentration under varying RH conditions.
• Thermodynamic parameters (Ea, ΔH≠, ΔS≠) were calculated, providing insights into the degradation energy barriers.

Conclusions:

• The solid-state degradation of clavulanate potassium is a complex process influenced by environmental factors and excipient interactions.
• The study provides critical data for optimizing storage conditions and formulation strategies to enhance clavulanate potassium stability.
• Computational and spectroscopic data aid in understanding the molecular-level degradation mechanisms.