A Semi‐Automated 96‐Well Solid Phase Extraction and High Performance Liquid Chromatographic Determination of a Selective GABA‐A Receptor Agonist in Human and Rat Plasma Using Fluorescence Detection

Abstract

A semi‐automated, 96‐well solid phase extraction (SPE) method combined with high performance liquid chromatography (HPLC) was developed, validated, and implemented to demonstrate its high sample throughput utility for the determination of a selective gamma amino‐butyric acid (GABA)‐A receptor agonist in human and rat plasma. A Tomtec Quadra 96 system was utilized to perform the typical 96‐well SPE steps, such as plate conditioning and washing, sample loading, drug and internal standard elution, dilution, and liquid transfers. The extracted and diluted eluents were analyzed by HPLC with fluorescence detection with excitation and emission wavelengths at 256 and 447 nm, respectively. Precision and accuracy for standard curve and quality control samples in human and rat plasma were all within acceptable limits. Post‐dose plasma samples from three rats were prepared and analyzed using this semi‐automated 96‐well SPE method. Full details of the analytical methodology, method validation, and the results of analyses of rat plasma samples are presented.

Keywords:

• 96‐Well solid phase extraction
• HPLC
• Fluorescence detection
• Selective GABA‐A receptor agonist
• Human and rat plasma

Acknowledgment

The authors would like to thank Ms. M. Cramer for dosing rats and collecting the rat plasma samples.