This is the way all fluorescence spectra are going to look.
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True excitation spectrum of anthracene (in ethanol). 5 η-ΐμ bandpass. Emission wavelength: 420 π\μ. It's the true fluorescence spec trum of anthracene, (above) re corded on Perkin-Elmer's new Model MPF-3 Fluorescence Spec trophotometer. It looks the way an excitation fluorescence spectrum was meant to look. Identical to its UV absorption spectrum—but re corded at a concentration 1000 times lower! Up to now fluorescence exci tation or emission spectra could not be used routinely between
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Absorption spectrum of anthracene (in ethanol). 5 τημ bandpass.
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Uncorrected excitation spectrum of anthracene (in ethanol). Emission wavelength: 420 χημ. laboratories or for publication be cause the relative intensities of peaks were incorrect. Incorrect because source and detector in teracted with spectra. Now, with our new MPF-3 you can record true band intensities permitting day-to-day, instru ment-to-instrument, and lab-to-lab cornparisons. C o m p a r i sons that are both easy and valid
You can begin to realize the full power of fluorescence spec trophotometry—its ability to meas ure nanogram levels (for pollutant analysis), to identify components in mixtures, to analyze powders and solids, to probe into living cell structure. If you want to make quantum efficiency measurements (to study rare earth phosphors, for exam ple) you're way ahead if your emission and excitation spectra are true and don't have to be corrected. What's more, you can make direct comparison of fluorescence excitation and UV/VIS absorp tion spectra published in litera ture and reference libraries. The new MPF-3, like the MPF2A which has become the relia bility standard for fluorescence spectrophotometers, has continu ously adjustable slits and high ef ficiency grating monochromators. This gives you greater precision in your quantitative analyses and more accurate working curves. And the wide range of accesso ries increases its versatility. Write for full information on the newest addition to PerkinElmer's Fluorescence Product line and we'll send you our bro chure and four technical reprints. If you own an MPF-2A, we can pro vide an accessory to give it the true s p e c t r a c a p a b i l i t y of t h e MPF-3. Write to Instrument Divi sion, Perkin-Elmer Corporation, 702 Main Avenue, Norwalk, Conn. 06852.
PERKIN-ELMER
Circle No. 142 on Readers' Service Card ANALYTICAL CHEMISTRY, VOL. 43, NO. 4, APRIL 1971 ·
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