Estimating the Solubility of Anthocyanins Using Cartridges for Solid-Phase Extraction

A method for using solid-phase extraction cartridges to estimate the solubility of anthocyanins is proposed. It is shown that at high degrees of the saturation of surfaces of sorbents by sorbates, their subsequent desorption using suitable extractants may be accompanied by the crystallization of sorbates after attaining supersaturation. The solubility of individual anthocyanins in a 1: 1 mixture of ethanol and 0.1 M HCl aqueous solution at the 12–13 g/L level is estimated using the proposed method. The total solubility of anthocyanins is found to grow after increasing the number of individual types of anthocyanins in mixture.