Quantitative profiling of 4'-geranyloxyferulic acid and its conjugate with l-nitroarginine methyl ester in mononuclear cells by high-performance liquid chromatography with fluorescence detection.

Oxyprenylated natural products were shown to exert in vitro and in vivo remarkable anti-cancer and anti-inflammatory effects. This paper describes a rapid, selective, and sensitive HPLC method with fluorescence detection for determination of 4'-geranyloxyferulic acid (GOFA) and its conjugate with l -nitroarginine methyl ester (GOFA-L-NAME) in mononuclear cells. Analytes were extracted from cells using methanol and eluted on a GraceSmart RP 18 analytical column (250 × 4.6 mm i.d., 5 μm particle size) kept at 25 °C. A mixture of formic acid 1% in water (A) and methanol (B) were used as mobile phase, at a flow-rate of 1.2 mL/min in gradient elution. A fluorescence detector (excitation/emission wavelength of 319/398 nm for GOFA and GOFA-L-NAME), was used for the two analytes. Calibration curves of GOFA and GOFA-L-NAME were linear over the concentration range of 1.0–50 μg/mL, with correlation coefficients ( r 2 ) ≥ 0.9995. Intra- and inter-assay precision do not exceed 6.8%. The accuracy was from 94% to 105% for quality control samples (2.0, 25.0 and 40 μg/mL). The mean (RSD%) extraction recoveries (n = 5) for GOFA and GOFA-L-NAME from spiked cells at 2.0, 25.0 and 40.0 μg/mL were 92.4 ± 1.5%, 94.7 ± 0.9% and 93.8 ± 1.1%, for GOFA and 95.3 ± 1.2%, 94.8 ± 1.0% and 93.9 ± 1.3%, for GOFA-L-NAME. The limits of detection and quantification were 0.3 μg/mL and 1.0 μg/mL for GOFA and GOFA-L-NAME. This method was successfully applied to measure GOFA and GOFA-L-NAME concentrations in a mononuclear cells. [ABSTRACT FROM AUTHOR]