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ASTM E578-07

(Test Method)

Standard Test Method for Linearity of Fluorescence Measuring Systems

Standard Test Method for Linearity of Fluorescence Measuring Systems

SIGNIFICANCE AND USE
The range of concentration of a fluorescing substance in solution over which the fluorescence varies linearly with the concentration is the range most useful for quantitative analysis. This range is affected by properties of the solution under analysis and by features of the measuring system. This test method provides a means of testing the performance of a fluorescence measuring system and of determining the concentration range over which the system is suitable for making a given quantitative analysis.
This test method is not meant for comparing the performance of different fluorescence measuring instruments.
SCOPE
1.1 This test method covers a procedure for evaluating the limits of the linearity of response with fluorescence intensity of fluorescence-measuring systems under operating conditions. Particular attention is given to slit widths, filters, and sample containers. This test method can be used to test the overall linearity under a wide variety of instrumental and sampling conditions. The results obtained apply only to the tested combination of slit width and filters, and the size, type and illumination of the sample cuvette, all of which must be stated in the report. The sources of nonlinearity may be the measuring electronics, excessive absorption of either the exciting or emitted radiation, or both, and the sample handling technique, particularly at low concentrations.
1.2 This test method has been applied to fluorescence-measuring systems utilizing continuous and low-energy excitation sources (for example, an excitation source of 450-W electrical input or less). There is no assurance that extremely intense illumination will not cause photodecomposition of the compounds suggested in this test method. For this reason it is recommended that this test method not be indiscriminately employed with high-intensity light sources. It is not a test method to determine the linearity of response of other materials. If this test method is extended to employ other chemical substances, the principles within can be applied, but new material parameters, such as the concentration range of linearity, must be established. The user should be aware of the possibility that these other substances may undergo decomposition, or adsorption onto containers.
1.3 This test method has been applied to fluorescence-measuring systems utilizing a single detector, that is, a photomultiplier tube or a single photodiode. It has not been demonstrated if this method is effective for photo-array instruments such as those using a CCD or a diode array detector.
1.4 This test method is applicable to 10-mm pathlength cuvette formats and instruments covering a wavelength range within 190 to 900 nm. The use of other sample formats has not been established with this test method.
This standard does not purport to address all of the safety concerns, 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.

General Information

Status
Historical
Publication Date
28-Feb-2007
ICS
17.180.30 - Optical measuring instruments
Technical Committee
E13 - Molecular Spectroscopy and Separation Science
Drafting Committee
E13.01 - Ultra-Violet, Visible, and Luminescence Spectroscopy
Current Stage
Ref Project

Relations

Replaces
ASTM E578-01 - Standard Test Method for Linearity of Fluorescence Measuring Systems
Effective Date
01-Mar-2007
Referred By
ASTM E579-04(2023) - Standard Test Method for Limit of Detection of Fluorescence of Quinine Sulfate in Solution
Effective Date
01-Mar-2007
Referred By
ASTM E2719-09(2022) - Standard Guide for Fluorescence—Instrument Calibration and Qualification
Effective Date
01-Mar-2007
Referred By
ASTM E2143-01(2021) - Standard Test Method for Using Field-Portable Fiber Optics Synchronous Fluorescence Spectrometer for Quantification of Field Samples for Aromatic and Polycyclic Aromatic Hydrocarbons
Effective Date
01-Mar-2007
Referred By
ASTM D5412-93(2017)e1 - Standard Test Method for Quantification of Complex Polycyclic Aromatic Hydrocarbon Mixtures or Petroleum Oils in Water
Effective Date
01-Mar-2007
Referred By
ASTM E3029-15(2023) - Standard Practice for Determining Relative Spectral Correction Factors for Emission Signal of Fluorescence Spectrometers
Effective Date
01-Mar-2007

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ASTM E578-07 - Standard Test Method for Linearity of Fluorescence Measuring Systems
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E578 − 07
StandardTest Method for
1
Linearity of Fluorescence Measuring Systems
This standard is issued under the fixed designation E578; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.4 This test method is applicable to 10-mm pathlength
cuvette formats and instruments covering a wavelength range
1.1 This test method covers a procedure for evaluating the
within190to900nm.Theuseofothersampleformatshasnot
limitsofthelinearityofresponsewithfluorescenceintensityof
been established with this test method.
fluorescence-measuring systems under operating conditions.
1.5 This standard does not purport to address all of the
Particular attention is given to slit widths, filters, and sample
safety concerns, if any, associated with its use. It is the
containers. This test method can be used to test the overall
responsibility of the user of this standard to establish appro-
linearity under a wide variety of instrumental and sampling
priate safety and health practices and determine the applica-
conditions. The results obtained apply only to the tested
bility of regulatory limitations prior to use.
combination of slit width and filters, and the size, type and
illumination of the sample cuvette, all of which must be stated
2. Summary of Test Method
inthereport.Thesourcesofnonlinearitymaybethemeasuring
electronics, excessive absorption of either the exciting or 2.1 This procedure is used for testing the linearity of
emitted radiation, or both, and the sample handling technique, fluorescence-measuring systems by using solutions of quinine
particularly at low concentrations. sulfate dihydrate in sulfuric acid as standard test solutions.
Other stable solutions which may be more suitable to the user
1.2 This test method has been applied to fluorescence-
can be employed (Note 1). The standard used to determine
measuring systems utilizing continuous and low-energy exci-
linearity should be stated in the report.The fluorescence of the
tation sources (for example, an excitation source of 450-W
test solution is measured in the measuring system with the
electrical input or less). There is no assurance that extremely
cuvettes, slits, or filters that are to be employed in projected
intense illumination will not cause photodecomposition of the
use.
2
compounds suggested in this test method. For this reason it is
NOTE1—Asubstitutestandardshouldhavethefollowingproperties:(1)
recommended that this test method not be indiscriminately
Itshouldhavealargequantumyieldatveryhighdilution;(2)itshouldbe
employed with high-intensity light sources. It is not a test
stable to the exciting radiation during spectral measurements; (3) its
method to determine the linearity of response of other materi-
fluorescence and its absorption spectra overlap should be small; (4) its
als. If this test method is extended to employ other chemical
quantum yield should not be strongly concentration dependent; and (5)it
substances, the principles within can be applied, but new should have a broad emission spectrum, so that little error is introduced
3
when wide slits are used.
material parameters, such as the concentration range of
linearity, must be established. The user should be aware of the
2.2 Upper Limit of Linearity—The fluorescence intensity of
possibility that these other substances may undergo
a series of standard solutions is measured, the resultant
decomposition, or adsorption onto containers.
instrument readings are plotted against concentration on a
log-log graph, and a smooth curve is drawn through the data
1.3 This test method has been applied to fluorescence-
points.The point (concentration) at which the upper end of the
measuring systems utilizing a single detector, that is, a photo-
curvedeviatesbymorethan5%ofthesignalfromthestraight
multiplier tube or a single photodiode. It has not been demon-
line (defined by the center region of the curve) is taken as the
strated if this method is effective for photo-array instruments
upper limit of linearity. The limit is expressed in micrograms
such as those using a CCD or a diode array detector.
per millilitre of quinine sulfate dihydrate.
NOTE 2—Absorption of the exciting radiation at high solute concentra-
tions is dependent on instrument geometry and pathlength, and can result
1
This test method is under the jurisdiction of ASTM Committee E13 on
in fluorescence signal nonlinearity.
Molecular Spectroscopy and Separation Science and is the direct responsibility of
Subcommittee E13.01 on Ultra-Violet, Visible, and Luminescence Spectroscopy.
2.3 LowerLimitofLinearity—Thelowerlimitoflinearityis
Cur
...

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SCOPE
1.1 This guide covers Raman shift values for common liquid and solid chemicals that can be used for wavenumber calibration of Raman spectrometers. The guide does not include procedures for calibrating Raman instruments. Instead, this guide provides reliable Raman shift values that can be used as a complement to low-pressure arc lamp emission lines which have been established with a high degree of accuracy and precision.  
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4.1 This practice permits an analyst to compare the performance of an instrument to the manufacturer's supplied performance specifications and to verify its suitability for continued routine use. It also provides generation of calibration monitoring data on a periodic basis, forming a base from which any changes in the performance of the instrument will be evident.
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1.1 This practice describes two levels of tests to measure the performance of laboratory Fourier transform mid-infrared (FT-MIR) spectrometers equipped with a standard sample holder used for transmission measurements.  
1.2 This practice is not directly applicable to Fourier transform infrared (FT-IR) spectrometers equipped with various specialized sampling accessories such as flow cells or reflectance optics, nor to Fourier transform near-infrared (FT-NIR) spectrometers, nor to FT-IR spectrometers run in step scan mode.  
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Standard Practice for Estimation of the Spectral Bandwidth of Ultraviolet-Visible Spectrophotometers

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4.1 These practices should be used by a person who develops an analytical method to ensure that the spectral bandwidths cited in the practice are actually the ones used.
Note 2: The method developer should establish the spectral bandwidths that can be used to obtain satisfactory results.  
4.2 These practices should be used to determine whether a spectral bandwidth specified in a method can be realized with a given spectrophotometer and thus whether the instrument is suitable for use in this application. If accurate absorbance measurements are to be made on compounds with sharp absorption bands (natural half band widths of less than 15 nm) the spectral bandwidth of the spectrometer used should be better than 1/8th of the natural half band width of the compound’s absorption.  
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SCOPE
1.1 This practice describes procedures for estimating the spectral bandwidth of a spectrophotometer in the wavelength region of 185 nm to 820 nm.  
1.2 These practices are applicable to all modern spectrophotometer designs utilizing computer control and data handling. This includes conventional optical designs, where the sample is irradiated by monochromatic light, and ‘reverse’ optic designs coupled to photodiode arrays, where the light is separated by a polychromator after passing through the sample. For spectrophotometers that utilize servo-operated slits and maintain a constant period and a constant signal-to-noise ratio as the wavelength is automatically scanned, and/or utilize fixed slits and maintain a constant servo loop gain by automatically varying gain or dynode voltage, refer to the procedure described in Annex A1. This procedure is identical to that described in earlier versions of this practice.  
1.3 This practice does not cover the measurement of limiting spectral bandwidth, defined as the minimum spectral bandwidth achievable under optimum experimental conditions.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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Standard Practice for Open-Path Fourier Transform Infrared (OP/FT-IR) Monitoring of Gases and Vapors in Air

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4.1 An OP/FT-IR monitor can, in principle, measure the concentrations of all IR-active gases and vapors in the atmosphere. Detailed descriptions of OP/FT-IR systems and the fundamental aspects of their operation are given in Practice E1685 and the FT-IR Open-Path Monitoring Guidance Document. A method for processing OP/FT-IR data to obtain the concentrations of gases over a long, open path is given in Compendium Method TO-16. Applications of OP/FT-IR systems include monitoring for gases and vapors in ambient air, along the perimeter of an industrial facility, at hazardous waste sites and landfills, in response to accidental chemical spills or releases, and in workplace environments.
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1.1 This practice covers procedures for using active open-path Fourier transform infrared (OP/FT-IR) monitors to measure the concentrations of gases and vapors in air. Procedures for choosing the instrumental parameters, initially operating the instrument, addressing logistical concerns, making ancillary measurements, selecting the monitoring path, acquiring data, analyzing the data, and performing quality control on the data are given. Because the logistics and data quality objectives of each OP/FT-IR monitoring program will be unique, standardized procedures for measuring the concentrations of specific gases are not explicitly set forth in this practice. Instead, general procedures that are applicable to all IR-active gases and vapors are described. These procedures can be used to develop standard operating procedures for specific OP/FT-IR monitoring applications.  
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Standard Test Method for Linearity of Fluorescence Measuring Systems

SIGNIFICANCE AND USE
3.1 The range of concentration of a fluorescing substance in solution over which the fluorescence varies linearly with the concentration is the range most useful for quantitative analysis. This range is affected by properties of the solution under analysis and by features of the measuring system. This test method provides a means of testing the performance of a fluorescence measuring system and of determining the concentration range over which the system is suitable for making a given quantitative analysis.  
3.2 This test method is not meant for comparing the performance of different fluorescence measuring instruments.
SCOPE
1.1 This test method covers a procedure for evaluating the limits of the linearity of response with fluorescence intensity of fluorescence-measuring systems under operating conditions. Particular attention is given to slit widths, filters, and sample containers. This test method can be used to test the overall linearity under a wide variety of instrumental and sampling conditions. The results obtained apply only to the tested combination of slit width and filters, and the size, type and illumination of the sample cuvette, all of which must be stated in the report. The sources of nonlinearity may be the measuring electronics, excessive absorption of either the exciting or emitted radiation, or both, and the sample handling technique, particularly at low concentrations.  
1.2 This test method has been applied to fluorescence-measuring systems utilizing continuous and low-energy excitation sources (for example, an excitation source of 450 W electrical input or less). There is no assurance that extremely intense illumination will not cause photodecomposition of the compounds suggested in this test method.2 For this reason it is recommended that this test method not be indiscriminately employed with high-intensity light sources. It is not a test method to determine the linearity of response of other materials. If this test method is extended to employ other chemical substances, the principles within can be applied, but new material parameters, such as the concentration range of linearity, must be established. The user should be aware of the possibility that these other substances may undergo decomposition, or adsorption onto containers.  
1.3 This test method has been applied to fluorescence-measuring systems utilizing a single detector, that is, a photomultiplier tube or a single photodiode. It has not been demonstrated if this method is effective for photo-array instruments such as those using a CCD or a diode array detector.  
1.4 This test method is applicable to 10 mm pathlength cuvette formats and instruments covering a wavelength range within 190 nm to 900 nm. The use of other sample formats has not been established with this test method.  
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 concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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