The first one is due to the oxidation of leucoindigo to indigo and the second one to the conversion of indigo to dehydroindigo. Indigo carmine is a purple powder with a molecular weight of 466.36. Uncorrected excitation and em ission spectra of indigo carmine dye in m ethanol (l ex and l e m represent the excitation and emission wavelengths , respectively).
Unit Chemistry of Textiles Dyeing Fibres
On the other hand, the absorbance of indigo carmine presents a spectrum ranging from 550 nm to 700 nm with a broad peak at 610 nm.
Acvs of indigo carmine show two peaks at around −0.1 and +0.7 v.
The first maximum lies at 210nm (about 3au) and the second at 250nm (about 0.1au). The change in color of the dye is directly proportional to the amount of dissolved oxygen. Indigo carmine is a chemical compound with an absorbance peak at 289 nm. Spectrum is shown in figure 1 for the leuco and keto forms of indigo.
The phenylalanine spectrum (100mg/l) shows two absorption maxima.
Elimination of the dye begins soon after injection, appearing in the urine within 10 minutes in average cases. The black curve indicates the absorption spectrum before the discharge treatment and the other curves are the spectra obtained with changing the discharge treatment time from 20 to 120 min. Absorption spectra were recorded from 190 to 1 100 nm and color removal efficiency was calculated with readings at ic λ max (610 nm). Spectral analysis of pure chemicals revealed that the absorption spectrum of indigo carmine widely overlapped with the fluorescence spectrum of ppix specifically at the peak of 632nm, a common emission wavelength for detecting ppix, but not at the other peak of 700nm.
The minimum between them (0.03au) divides both absorption bands.
It is sometimes also known as acid blue 74. Indigo carmine is excreted largely by the kidneys, retaining its blue color during passage through the body. The full spectrum can only be viewed using a free account. As cu(ii) or indigo carmine does not absorb in this range.
In practice, the fluorescence intensity of ppix solution was attenuated by mixture with indigo carmine.
The first one is due to the oxidation of leucoindigo to indigo and the second one to the conversion of indigo to dehydroindigo. The absorbance of indigo carmine at 700 nm was as low as 3.7% of that at 632 nm. More information on the manner in which spectra in this collection were collected can be found here. This report investigates the absorbance of methylene blue and carmine red using a spectrophotometer to determine the absorption spectra of both solutions.
