Bioanalytical Systems, Inc., 2701 Kent Avenue, West Lafayette, IN, 47906
To develop a method for the quantitation of pamoic acid in human, rat and canine plasma.
Pamoic acid is an aromatic dicarboxylic acid used as an adjuvant to prolong therapeutic action. Pamoic acid and internal standard are extracted from plasma by protein precipitation. The supernatant is evaporated to dryness, reconstituted in a buffer, and then loaded onto SPE cartridges. Extracts are injected onto an HPLC system utilizing a YMC Basic column with a buffer/ion pair reagent/acetonitrile mobile phase.
The three different matrices yielded successfully validated methods. The resulting assays were sensitive, selective, accurate and precise. Inter-assay precision and accuracy for pamoic acid ranged from: 5.3% to 8.5% and -9.6% to -6.2%, respectively (rat plasma) and 7.8% to 11.4% and -1.4% to 0.3%, respectively (human plasma). The method was subsequently cross-validated into canine plasma.
This assay serves as a specific and sensitive analytical method to aid in pharmacokinetic measurements of pamoic acid in three different matrices.
*Jorgensen, Martin. “Quantitative determination of pamoic acid in dog and rat serum by automated ion-pair solid-phase extraction and reversed-phase high-performance liquid chromatography”; J. Chrom. B, 716 (1998), 315-323.
Sample volume: 0.5 mL
Column: YMC Basic 150 x 4.6 mm, 5 µm (and guard)
Mobile phase: 52% acetonitrile / 48% phosphate buffer (10 mM),
cetyltrimethylammonium hydrogensulfate (5 mM)
Flow rate: 0.8 mL/min
Fluorescence detection: Î»ex = 240 nm, Î»em = 523 nm
Injection volume: 35 µL