Fluorescence of berberine in microheterogeneous systems

Spectral properties of the alkaloid berberine were studied in micellar solution and microemulsions based on anionic sodium dodecyl sulfate, cationic cetyltrimethylammonium bromide and nonionic Triton X-100 surfactants. Absorption and fluorescence emission spectra were determined. For screening the influence of type and concentration of micelles on the fluorescence of berberine a 32 full factorial design was used. Higher responses were obtained when berberine was dissolved in sodium dodecyl sulfate micelles 0.01 M. Comparative results of fluorescence quantum yields (Φf) reveal that the highest values (Φf≥0.01) were observed in microemulsions. In the microheterogeneous systems investigated the most probable location of berberine is the micellar interfacial region.