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AssigneeSequoia-Turner Corporation
InventorsAndrew Stefanski, Alfred H. Sturtevant, Michael G. Konicek, Peter E. Lobban
Estimating the term…
Variations in the intensity of a light source and the sensitivity of a fluorescence detector photo-multiplier tube are simultaneously compensated by measuring the intensity (I.sub.LS1) of the light source at the sample excitation frequency with a silicon detector, measuring the intensity (I.sub.LS2) of the light source at the emission frequency with another silicon detector, measuring with the photo-multiplier detector the intensity (I.sub.S) of the sample's fluorescence and the intensity (I.sub.LS3) of the light source at the emission frequency of the sample and then calculating a value F as representative of the sample's fluorescence according to the formula: ##EQU1##
In a method of fluorescence detection wherein a light source of a first predetermined wavelength is shone on a sample and the intensity (I.sub.S) of the fluorescence from the sample at a second predetermined wavelength is detected by a detector a, the improvement comprising the steps of sensing the intensity (I.sub.LSI) of the light source at the first predetermined wavelength by a detector b, sensing the intensity (I.sub.LS2) of the light source at the second predetermined wavelength with a detector c, sensing the intensity (I.sub.LS3) of the light source at the second predetermined wavelength with the detector a, and deriving a value F representing the fluorescence of the sample by combining the detected intensities according to the formula:
Apparatus for fluorescence analysis of a sample, comprising a source for shining light at an excitation frequency on the sample, a detector b for monitoring the intensity of the light shown on the sample at the excitation frequency and for producing an electronic output signal, I.sub.LS1, corresponding thereto, a detector c for monitoring the intensity of the light source at an emission frequency, corresponding to the frequency of light emitted due to fluorescence of the sample caused by the light source, and for producing an electronic output signal, I.sub.LS2, corresponding thereto, a detector a which produces an electronic output signal I.sub.S corresponding to the intensity of light at the emission frequency received from the sample due to fluorescence by the light source and an electronic output signal I.sub.LS3 corresponding to the intensity of the light source at the emission frequency, and means supplied with the electronic signals I.sub.S, I.sub.LS1, I.sub.LS2 and I.sub.LS3 for generating an electronic signal F where:
Dependencies are inferred from the claim text.