Determination of 3, 4‐dihydroxyphenylglycol (DHPG) by HPLC with coulometric detection, and correlation with 3‐methoxy‐4‐hydroxyphenylglycol (MHPG) in human plasma

Abstract

A method for determining plasma 3,4-dihydroxyphenylethyleneglycol (DHPG), a central noradrenaline (NA) metabolite, is described. The method used HPLC with dual coulometric detection set in screen mode of operation. The isolation of DHPG and related catecholamines (noradrenaline, dopamine and dihydroxybenzylamine) was performed on acid washed alumina extracted with 0.2 M HCIO4 containing EDTA (0.2%), and reduced glutathione as stabilizer. A reversed phase column with an eluting system containing 0.025 M citric acid-sodium hydrogen phosphate buffer in the ratio 3:2 (v:v) and 5% methanol was used. The experimental results of plasma DHPG levels compared favourably with the results from the literature, and a positively significant correlation with plasma MHPG was found. This method could be used as an alternative in central NA assessment.

Determination of 3,4-dihydroxyphenylglycol, hydroxytyrosol and tyrosol purified from olive oil by-products with HPLC in animal plasma and tissues

“…Various individual analytical methods exist to determine levels of different phenols, such as DHPG, hydroxytyrosol or tyrosol in plasma, urine and brain tissue using HPLC, GC-MS and colorimetric methods (Eisenhofer et al, 1986;Grizis, Atta-Politou, & Koupparis, 2003;Karege, Gaillard, Tissot, Azorin, & Valli, 1987;Nielsen & Braestrup, 1976;Ruiz-Gutierrez, Juan, Cert, & Planas, 2000;Sastre, Nicolay, Bruguerolle, & Portugal, 2004;Tan, Tuck, Stupans, & Hayball, 2003; Venneri & Del Rio, 2004;Wu et al, 2009;Xie, Suckow, & Cooper, 1996). Here we describe the development of a novel and simple method to quantify, simultaneously, DHPG, hydroxytyrosol and tyrosol extracted and purified from olive oil by-product in (rat) plasma and tissues samples using an HPLC method with UV-Vis detection.…”