A UHPLC method for the rapid separation and quantification of anthocyanins in acai berry and dry blueberry extracts
Abstract
The presented work describes the development and validation of a rapid UHPLC-UV method using a core-shell particle column with a pentafluorophenyl stationary phase for the separation and quantitative analysis of the six anthocyanins in acai berry and dry blueberry extracts. The anthocyanins (cyanidin-3-glucoside, cyanidin-3-rutenoside, delphinidin-3-galactoside, delphinidin-3-glucoside, delphinidin-3-rutenoside, and peonidin-3-glucoside) were separated and analyzed in 5 min.
The chromatographic separation was performed on a Kinetex PFP (150 x 2.1 mm) core-shell column with a particle size of 1.7 mu m at a temperature of 50 degrees C. Acetonitrile was used as mobile phase B and 5% formic acid, filtrated through a 0.22 mu m filter, as mobile phase A.
They were delivered at a flow rate of 0.55 mL min(-1) according to the elution gradient program. The detection wavelength was set at 520 nm.
A solid-liquid extraction with a solution of methanol and a 5% water solution of formic acid (25+75 v/v) using an ultrasonic bath was chosen for the preparation of the available commercial samples of food supplements with a content of acai berry extract and blueberry extract. Under optimal chromatographic conditions, the method was validated.
Recoveries for all analyzed anthocyanins were 97.8-102.6% and the relative standard deviation ranged from 0.4% to 3.0% for within-day and from 0.6% to 3.1% for between-day repeatability. The limits of detection were in the range of 0.11-0.14 mu g mL(-1).