Validated HPLC method for the quantitative determination of CoQ₁₀ in dog plasma and its application to a pharmacokinetic study

Abstract

Coenzyme Q(10) (CoQ(10) ) is a naturally occurring compound located in all membranes throughout the cell. A rapid and sensitive HPLC method was developed to determine the concentration of CoQ(10) in dog plasma using a surrogate matrix. Chromatographic separation was carried out on a Diamonsil C(18) column with the UV detector set at 275 nm. Methanol-2-propanol (40:60, v/v) was used as a mobile phase delivered at a flow rate of 1.0 mL/min. Calibrators were prepared using blank plasma-K(2) HPO(4) buffer (50 mm, pH 8.0)-saline (1:3:6, v/v/v) as surrogate matrix. It was shown that the surrogate matrix had similar properties to dog plasma for CoQ(10) in extraction, freeze-thaw and stability. The assay was linear over the concentration range of 0.10-100 µg/mL. The intra- and inter-day precisions were within 13.3% in terms of relative standard deviation (RSD%) and the accuracy was within ±7.5% in terms of relative error. This simple and reproducible HPLC method with less plasma volume (0.4 mL) and adequate sensitivity was successfully applied to pharmacokinetic studies of CoQ(10) in dogs and an investigation of the effect of CoQ(10) formulation on CoQ(10) baseline levels.

Pharmacokinetics of Repeated Oral Dosing with Coenzyme Q10 in Cavalier King Charles Spaniels with Myxomatous Mitral Valve Disease

“…Endogenous concentrations of circulating Q10 in laboratory-bred [31,[33][34][35] and privately-owned dogs [16,17] were similar to human endogenous reference levels [15]. On this background, we applied the 2.0 µg/mL concentration as the primary endpoint.…”

Determination of Reduced and Oxidized Coenzyme Q10 in Canine Plasma and Heart Tissue by HPLC-ECD: Comparison with LC-MS/MS Quantification

“…Sample preparation and subsequent analysis is critical for determination of oxidation ratio due to instability of the reduced form of Q 10 [12,13]. Historically, high-performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) has been used for quantification of the total Q 10 concentration [7,14]. In order to investigate the oxidation ratio, HPLC coupled to electrochemical detection (HPLC-ECD) has been used extensively, since oxidation ratio may be determined by performing reduction or oxidation in the electrochemical cell after chromatographic separation [13,15,16,17,18].…”

Determination by UPLC/MS-MS of Coenzyme Q10 (CoQ10) in Plasma of Healthy Volunteers before and after Oral Intake of Food Supplements Containing CoQ10

“…In this way we demonstrated that it is not necessary to store plasma sample at -20 or -80°C as stated in the literature [1,4,8] for the analysis of CoQ10, thus simplifying the analytical procedure. In fact the analysis of frozen samples is more difficult and longer.…”

“…Coenzyme Q10 (CoQ10; 2,3-dimethoxy-5-methyl-6-polipropenyl-1,4-benzoquinone), also known as ubiquinone 10, is a lipophilic naturally occurring compound located in all membranes of eukaryotic organisms [1]. It is a benzoquinone with 10 isoprene units in the aliphatic chain [2] and it is essential for electron transfer in the mitochondrial respiratory chain, playing a key role in energy metabolism as an integral part of the electron transport system [3,4].…”