Absorption Spectroscopic Determination of Solubility of Alloxazine in Aqueous Solutions

Alfons Penzkofer

Faculty of Physics, University of Regensburg, Regensburg, Germany.

DOI: 10.4236/jasmi.2015.52002                

Abstract

The solubility of alloxazine in aqueous solution at pH 4 (10^–4 molar HCl) and pH 10 (10^–4 molar NaOH) at room temperature is determined by absorption spectroscopic characterization. Knowledge of the solubility is needed for sample preparation and quantitative spectroscopic solution characterization. Samples of different in-weight concentration were prepared and absorption spectra were measured versus storage time. The solubility limit concentration C_sol was determined by the crossing point of the linearized absorption coefficient dependences on in-weight preparation concentration below and above the solubility limit. Values of C_sol= 9.05 ± 1 μM and 14.5 ± 1 μM were determined for alloxazine in aqueous solution at pH 4 and pH 10, respectively.

Keywords

Solubility Limit Concentration, Alloxazine, Isoalloxazine, Absorption Method, Aqueous Solutions

Conflicts of Interest

The authors declare no conflicts of interest.

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