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ASTM E579-04(2015)
Standard Test Method for Limit of Detection of Fluorescence of Quinine Sulfate in Solution
Automaticky přeložený název:
Standardní zkušební metoda pro mezí detekce fluorescence síranu chininu v roztoku
NORMA vydána dne 1.5.2015
Informace o normě:
Označení normy: ASTM E579-04(2015)
Poznámka: NEPLATNÁ
Datum vydání normy: 1.5.2015
Kód zboží: NS-590642
Počet stran: 3
Přibližná hmotnost: 9 g (0.02 liber)
Země: Americká technická norma
Kategorie: Technické normy ASTM
Kategorie - podobné normy:
Anotace textu normy ASTM E579-04(2015) :
Keywords:
fluorescence spectrometers, molecular luminescence, molecular spectroscopy,, ICS Number Code 71.080.30 (Organic nitrogen compounds)
Doplňující informace
| Significance and Use | ||
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4.1 When determining the limiting detectable concentration of a fluorescent substance, it is usually necessary to increase the readout scale of a photoelectric instrument to a point where noise (that is, random fluctuations of the system) becomes apparent. This noise will be superimposed upon the signal from the sample. 4.2 In molecular fluorescence spectroscopy, the limit of detection for the sample will be determined by the limiting signal-to-noise ratio, S/N, where the signal, S, is the difference between readings obtained with the sample and blank solutions, and N is the total root-mean-square (rms) noise. The limit of detection for the sample will be given by the instrument readings that give a signal equal to three times the rms value of the noise. Note 2: Factors other than noise affecting the sample
concentration corresponding to the limit of detection include: the
spectral bandwidths of the excitation and emission monochromators,
the intensity of the exciting light that can be concentrated on the
sample, the fraction of the fluorescence collected by the detection
system, the response time of the detection system, and the purity
of the solvent. The size and arrangement of the sample container
with respect to the light beams are also important, as they affect
both the desired signal and the extraneous signal that only
contributes noise.
1.1 This test method employs the
signal-to-noise ratio to determine the sensitivity of a
fluorescence measuring system in testing for the limit of detection
(LOD) of quinine sulfate dihydrate in solution. The results
obtained with quinine sulfate dihydrate in solution are suitable
for specifying instrument performance on samples having excitation
and fluorescence bands wider than 10 nm at or near room
temperature.
1.1.1 This test method is not intended to be used as (1.2 This test method has been applied to fluorescence-measuring systems utilizing non-laser, low-energy excitation sources. There is no assurance that extremely intense illumination will not cause photodecomposition2 of the compound suggested in this test method. For this reason, it is recommended that this test method not be indiscriminately employed with high intensity light sources. This test method is not intended to determine minimum detectable amounts of other materials. If this test method is extended to employ other chemical substances, the user should be aware of the possibility that these other substances may undergo decomposition or adsorption onto containers. 1.3 A typical LOD for conventional fluorometers using this test method is 1 ng of quinine sulfate per mL. 1.4 The suggested shelf life of a 1 mg/mL stock solution of quinine sulfate dihydrate is three months, when stored in the dark in a stoppered glass bottle. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. |
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| 2. Referenced Documents | ||
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