SET OF SECONDARY-EMISSION STANDARDS FOR CALIBRATION OF THE SPECTRAL RESPONSIVITY IN EMISSION-SPECTROSCOPY

Technical spectra are reported for a series of six secondary emission standards based on the commercially available fluorophors: tryptophan, alpha-NPO, tetraphenylbutadiene, coumarin 153, DCM, and LDS 751, Thes e spectra cover the wavelength range between 300 and 800 nm with signi ficant spectral overlap and conform to the requirements of secondary e mission standards. Standard emission spectra are determined by averagi ng the technical spectra obtained from three independently calibrated fluorescence spectrometers. A method for generating the wavelength-dep endent correction file by using these standards is outlined. Compariso n to the National Bureau of Standards (NBS)-reported quinine sulfate s pectrum illustrates the accuracy of both the emission standards and th e method of generating a complete emission correction file. With the u se of the standards and method reported here, the accuracy of the emis sion correction is estimated to be better than 10% for the entire wave length range and significantly better over the wavelength region of a typical spectrum.