Ripon College, Chemistry, Ripon, WI 54971
The luminol chemiluminescence test that is generally used to detect the presence of blood has been found to also produce false positive tests when reacted with several metal salt solutions. It was proposed by Terrance Quickenden that when luminol is mixed with colored salt solutions with absorption wavelengths in the visible range that the peak emission would be present at a different wavelength than that of luminol and hemoglobin. A luminol solution also containing sodium hydroxide was reacted with a 15 g/L hemoglobin solution the peak emission wavelength was found to be 431 nm. When the same luminol solution was tested with six different metal salt solutions combined with hydrogen peroxide, five of these solutions produced peak emissions at roughly the same wavelength. Potassium Ferricyanide produced a spectrum that showed evidence of color filtering with a λmax at 462 nm. This was confirmed when concentrations of the iron solution with different absorption wavelengths were found to give λmax values at 462 nm, 450 nm, and 366 nm. A luminol solution containing sodium carbonate and sodium perborate was tested with the hemoglobin solution and an altering λmax was found at 450 nm.
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