Abstract

• The natural dyes used in this research were poinsettia leaves (Coleus Blumei).The absorbance and energy levels of dyes solutions were characterized using UV-Vis spectrophotometer and cyclic voltammetry. From UV-Vis absorption spectrum and , it was known that combination of anthocyanin and chlorophyll with ethanol was the broader region of the visible light spectrum in the range of 400 to 700 nm compared to extracted with methanol. All dyes were measured under the different solvents and temperatures to estimate the energy of the highest occupied molecular orbital (HOMO) and the energy of lowest unoccupied molecular orbital (LUMO). Optical band gap was measured from the absorption spectrum of each dye sensitizer. Fourier transform inferred (FTIR) was used to characterize the dye active components from 4000 to 500 cm-1. From FTIR results, the coleus blumei match with AMANO LIPASE (C11 H9 N3 Na O2) compound corresponding to the carboxylic acidic group in dye solutions were observed.