ASTM D7730-11

Standard Test Method for Determination of Dioctyl Sulfosuccinate in Sea Water by Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

SIGNIFICANCE AND USE
DOSS is an anionic detergent that is approved by the Food and Drug Administration and is used widely as a laxative, emulsifying, solubilizing and dispersing agent, and is used in the cosmetic industry. DOSS may also be used as a dispersing agent to treat oil. DOSS may be released into the environment at levels that may be harmful to aquatic life. The US EPA aquatic life benchmark for DOSS is 40 ppb.  
This method has been investigated for use with reagent and sea water.
SCOPE
1.1 This procedure covers the determination of dioctyl sulfosuccinate (DOSS) in sea water by direct injection using liquid chromatography (LC) and detection with tandem mass spectrometry (MS/MS). This analyte is qualitatively and quantitatively determined by this method. This method adheres to selected reaction monitoring (SRM) mass spectrometry.
1.2 The Detection Verification Level (DVL) and Reporting Range for DOSS are listed in Table 1.
1.2.1 The DVL is required to be at a concentration at least 3 times below the Reporting Limit (RL) and have a signal/noise ratio greater than 3:1. Fig. 1 and Fig. 2 display the signal/noise ratio of the selected reaction monitoring (SRM) transition.
1.2.2 The reporting limit is the concentration of the Level 1 calibration standard as shown in Table 5 for DOSS, taking into account the 50% sample preparation dilution factor.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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.
TABLE 1 Detection Verification Level and Reporting Range  AnalyteDVL (μg/L)Reporting Range (μg/L) DOSS320-400
FIG. 1 Detection Verification Level Signal/Noise Ratio.
FIG. 2 Reporting Level Signal/Noise Ratio.

General Information

• Status: Historical
• Publication Date: 30-Apr-2011
• ICS: 71.060.50 - Salts
• Technical Committee: D19 - Water
• Drafting Committee: D19.06 - Methods for Analysis for Organic Substances in Water

Relations

• Replaced By: ASTM D7730-17 - Standard Test Method for Determination of Dioctyl Sulfosuccinate in Sea Water by Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)
• Effective Date: 15-Dec-2017

Standards Content (Sample)

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:D7730 −11
Standard Test Method for
Determination of Dioctyl Sulfosuccinate in Sea Water by
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/
MS)
This standard is issued under the fixed designation D7730; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.2 Other Standards:
EPApublication SW-846, Test Methods for Evaluating Solid
1.1 This procedure covers the determination of dioctyl
Waste, Physical/Chemical Methods
sulfosuccinate (DOSS) in sea water by direct injection using
liquid chromatography (LC) and detection with tandem mass
3. Terminology
spectrometry (MS/MS). This analyte is qualitatively and quan-
titatively determined by this method. This method adheres to 3.1 Definitions:
3.1.1 detection verification level, DVL, n— a concentration
selected reaction monitoring (SRM) mass spectrometry.
that has a signal/noise ratio greater than 3:1 and is at least 3
1.2 The Detection Verification Level (DVL) and Reporting
times below the Reporting Limit (RL).
Range for DOSS are listed in Table 1.
3.1.2 reporting limit, RL, n—the concentration of the
1.2.1 The DVL is required to be at a concentration at least
lowest-level calibration standard used for quantification.
3 times below the Reporting Limit (RL) and have a signal/
noise ratio greater than 3:1. Fig. 1 and Fig. 2 display the
3.2 Abbreviations:
signal/noise ratio of the selected reaction monitoring (SRM)
3.2.1 ppb—parts per billion, µg/L
-3
transition.
3.2.2 mM—millimolar,1x10 moles/L
1.2.2 The reporting limit is the concentration of the Level 1
3.2.3 NA—no addition
calibration standard as shown inTable 5 for DOSS, taking into
3.2.4 ND—non-detect
account the 50% sample preparation dilution factor.
4. Summary of Test Method
1.3 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
4.1 This is a performance based method, and modifications
standard.
are allowed to improve performance.
1.4 This standard does not purport to address all of the
4.2 For DOSS analysis, samples are shipped to the lab
safety concerns, if any, associated with its use. It is the
between 0°C and 6°C and analyzed within 5 days. In the lab,
responsibility of the user of this standard to establish appro-
the entire collected 20 mL sample is spiked with surrogate,
priate safety and health practices and determine the applica-
ammonium formate buffer solution and brought to a volume of
bility of regulatory limitations prior to use.
40 mL with acetonitrile. This prepared sample is then filtered
using a syringe driven filter unit, and analyzed by LC/MS/MS.
2. Referenced Documents
If visible oil is present, the prepared sample is allowed to settle
2.1 ASTM Standards: resulting in an oil layer at the top of the 40 mL solution. A
D1193 Specification for Reagent Water
portion of the aqueous (bottom) layer is filtered, leaving the oil
D2777 Practice for Determination of Precision and Bias of layer behind, through a syringe driven filter assembly and
Applicable Test Methods of Committee D19 on Water
analyzed by LC/MS/MS.
4.3 DOSS and DOSS surrogate are quantitated by retention
time and one SRM transition. The final report issued for each
This test method is under the jurisdiction of ASTM Committee D19 on Water
sample lists the concentration of DOSS and the surrogate
andisthedirectresponsibilityofSubcommitteeD19.06onMethodsforAnalysisfor
Organic Substances in Water.
recovery.
Current edition approved May 1, 2011. Published July 2011. DOI: 10.1520/
D7730–11.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from National Technical Information Service (NTIS), U.S. Depart-
Standards volume information, refer to the standard’s Document Summary page on ment of Commerce, 5285 Port Royal Road, Springfield, VA, 22161 or at http://
the ASTM website. www.epa.gov/epawaste/hazard/testmethods/index.htm
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7730−11
TABLE 1 Detection Verification Level and Reporting Range
Analyte DVL (µg/L) Reporting Range (µg/L)
DOSS 3 20-400
FIG. 1Detection Verification Level Signal/Noise Ratio.
FIG. 2Reporting Level Signal/Noise Ratio.
D7730−11
5. Significance and Use 7.1.2 Analytical Column—Waters—Atlantis™ dC18, 2.1 x
150 mm, 3 µm particle size was used to develop this test
5.1 DOSS is an anionic detergent that is approved by the
method.Any column that achieves baseline resolution of these
FoodandDrugAdministrationandisusedwidelyasalaxative,
analytes may be used. Baseline resolution simplifies data
emulsifying, solubilizing and dispersing agent, and is used in
4 analysis and can reduce the chance of ion suppression, leading
the cosmetic industry. DOSS may also be used as a dispersing
to higher limits of detection. The retention times and order of
agent to treat oil. DOSS may be released into the environment
elution may change depending on the column used and need to
at levels that may be harmful to aquatic life. The US EPA
be monitored.
aquatic life benchmark for DOSS is 40 ppb.
7.1.3 Tandem Mass Spectrometer System—A MS/MS sys-
5.2 This method has been investigated for use with reagent
tem capable of MRM analysis. Any system that is capable of
and sea water.
performing at the requirements in this standard may be used.
7.2 Filtration Device
6. Interferences
7.2.1 Hypodermic syringe—A Lock Tip Glass Syringe ca-
6.1 Method interferences may be caused by contaminants in
pable of holding a Millex® HV Syringe Driven Filter Unit
solvents, reagents, glassware, and other apparatus producing
PVDF 0.22 µm or similar may be used.
discrete artifacts or elevated baselines. All of these materials
7.2.1.1 A Lock Tip Glass Syringe was used in this test
are demonstrated to be free from interferences by analyzing
method.
laboratory reagent blanks under the same conditions as
7.2.2 Filter—Millex®HVSyringeDrivenFilterUnitPVDF
samples.
0.22 µm (Millipore Corporation, Catalog # SLGV033NS) or
6.2 All glassware is washed in hot water with detergent and similar may be used.
rinsed in hot water followed by distilled water. The glassware
is then dried and heated in an oven at 250°C for 15 to 30 8. Reagents and Materials
minutes. All glassware is subsequently cleaned with methanol
8.1 Purity of Reagents—High Performance Liquid Chroma-
or 50% acetonitrile/50% water, or both.
tography (HPLC) pesticide residue analysis and spectropho-
tometry grade chemicals shall be used in all tests. Unless
6.3 System contamination and surface binding are problem-
atic as DOSS is a surface active compound. It is important to indicated otherwise, it is intended that all reagents shall
conform to the Committee on Analytical Reagents of the
thoroughly rinse sample containers with organic solvent to
accurately measure DOSS concentrations. Thorough rinsing of American Chemical Society. Other reagent grades may be
all lab equipment is necessary to reduce contamination. Care- used provided they are first determined to be of sufficiently
fully analyze blanks to ensure that the method minimizes highpuritytopermittheirusewithoutaffectingtheaccuracyof
DOSS carryover. the measurements.
6.4 All reagents and solvents should be pesticide residue 8.2 Purity of Water—Unless otherwise indicated, references
purity or higher to minimize interference problems. towatershallbeunderstoodtomeanreagentwaterconforming
toType 1 of Specification D1193. It must be demonstrated that
6.5 Matrix interferences may be caused by contaminants in
this water does not contain contaminants at concentrations
the sample. The extent of matrix interferences can vary
sufficient to interfere with the analysis.
considerably from sample source depending on variations of
the sample matrix. 8.3 Gases—Ultrapure nitrogen and argon.
8.4 Acetonitrile (CH CN, CAS # 75-05-8).
6.6 Sulfonate filters contribute significantly to background
interference and should be avoided for this standard. In
8.5 Methanol (CAS # 67-56-1).
addition to sample filtration, sulfonate filters may be present in
8.6 Ammonium formate (NH CO H, CAS # 540-69-2).
4 2
water purification systems.
8.7 2-Propanol (CAS # 67-63-0).
7. Apparatus
8.8 Dioctyl sulfosuccinate (DOSS) purchased as the sodium
7.1 LC/MS/MS System
salt (CAS # 577-11-7).
7.1.1 Liquid Chromatography System—Acomplete LC sys-
8.9 Dioctyl sulfosuccinate- C , (bis(2-ethylhexyl) sulfos-
tem is needed in order to analyze samples. Any system that is 13
uccinate (Fumaric acid- C ) sodium salt (Unlabeled CAS #
capable of performing at the flows, pressures, controlled
577-11-7), (Optional Surrogate, custom synthesis).
temperatures, sample volumes, and requirements of the stan-
dard may be used.
A Waters Quattro Premier™ XE tandem quadrupole mass spectrometer was
usedtodevelopthistestmethod.Allparametersinthistestmethodarebasedonthis
Code of Federal Regulations-Title 21: Food and Drugs, Part 172 available at system and may vary depending on your instrument.
http://www.gpoaccess.gov/cfr/index.html. Reagent Chemicals, American Chemical Society Specifications, American
Additional information about DOSS is available at http://www.epa.gov/bpspill/ Chemical Society, Washington, D.C. For Suggestions on the testing of reagents not
dispersant-methods.html (2010) listed by the American Chemical Society, see Annual Standards for Laboratory
A Waters ACQUITY UltraPerformance Liquid Chromatography (UPLC®) Chemicals,BDHLtd.,Poole,Dorset,U.K.,andtheUnitedStatesPharmacopeiaand
System was used to develop this test method.All parameters in this test method are National Formulators, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
based on this system and may vary depending on your instrument. MD.
D7730−11
8.10 Dioctyl sulfosuccinate-D (DOSS-D ), bis(2- another, greater than half the reporting limit, the initial per-
34 34
ethylhexyl-D ) sulfosuccinate sodium salt (Unlabeled CAS # centage of acetonitrile should be raised as shown in Table 3 to
577-11-7). try and remove the carry-over. This will shorten the elution
timeofDOSSapproximately1minute;thereforeitisnecessary
9. Hazards
reducetheflowdiversionandadjusttheMRMtime.Increasing
the initial acetonitrile gradient concentration does not increase
9.1 Normal laboratory safety applies to this method. Ana-
the DVL or reporting limit.
lysts should wear safety glasses, gloves, and lab coats when
working in the lab.Analysts should review the Material Safety
11.2 LC Sample Manager Conditions :
Data Sheets (MSDS) for all reagents used in this method.
11.2.1 Wash Solvents—Weak wash is 4.0 mLof 50% water/
50% acetonitrile. Strong wash is 2.0 mL of 60% acetonitrile/
10. Sampling
40% 2-propanol. The strong wash solvent is needed to elimi-
10.1 Sampling and Preservation—Grab samples should be
nate carry-over between injections of DOSS samples. The
collected in 20 mL pre-cleaned glass vials with Teflon® lined
weak wash is used to remove the strong wash solvent.
septa caps demonstrated to be free of interferences. This test
Instrument manufacturer specifications should be followed in
method is based on a 20 mL sample size per analysis. Each
order to eliminate sample carry-over.
sample should be collected in duplicate and a quadruplicate
11.2.2 Temperatures—Column, 35°C; Sample
sample must be included with each sample batch of 10 for
compartment, 15°C.
MS/MSD quality control analyses. Store samples between 0°C
11.2.3 Seal Wash—Solvent: 50% acetonitrile/50% water;
and 6°C from the time of collection until analysis.Analyze the
Time: 2 minutes.
sample within 5 days of collection.
11.3 Mass Spectrometer Parameters :
10.2 DOSS is surface active. The surface activity results in
11.3.1 To acquire the maximum number of data points per
DOSS adhering to many materials. Sampling techniques that
SRM channel while maintaining adequate sensitivity, the tune
expose samples to materials other than the sample container
parameters may be optimized according to your instrument.
may reduce DOSS concentration in samples. Sampling tech-
Each peak requires at least 10 scans per peak for adequate
niques such as peristaltic pumping expose the sample to large
quantitation. This procedure will contain one surrogate, which
surface areas compared to sample volume. Grab sampling
is isotopically labeled DOSS, DOSS-quantitation and DOSS-
techniques should be used. Transferring of sample from an
confirmation are in one MRM acquisition function to optimize
initial collection device to sampling vial may result in biased
sensitivity. Variable parameters regarding retention times,
low DOSS concentrations and must be avoided.
SRM transitions, and cone and collision energies are shown in
Table 4. Mass spectrometer parameters used in the develop-
11. Preparation of LC/MS/MS
ment of this method are listed below:
11.1 LC Chromatograph Operating Conditions The instrument is set in the Electrospray negative source
11.1.1 Injection volumes of all calibration standards and setting.
samples are made at 50 µL volume using a full loop injection. Capillary Voltage: 3.5 kV
“Full loop” mode is the preferred technique when performing Cone: Variable depending on analyte (Table 4)
quantitative analyses. Multiple blank samples should be ana- Extractor: 2 Volts
lyzed at the beginning of a run to remove residual DOSS from
RF Lens: 0.3 Volts
the system. The first sample analyzed after the calibration Source Temperature: 120°C
curve is a blank to ensure there is negligible (Less than the Desolvation Temperature: 350°C
DVL) DOSS carry-over. The gradient conditions for the liquid Desolvation Gas Flow: 800 L/hr
chromatograph are shown in Table 2. Divert the column flow Cone Gas Flow: 25 L/hr
away from the electrospray source for 0 to 5 minutes after Low Mass Resolution 1: 14.0
injection. Flow diversion to waste may be done using the mass High Mass Resolution 1: 14.0
spectrometer divert valve, divert tubing configurations vary Ion Energy 1: 0.8
from manual injection. Test the divert valve configuration and Entrance Energy: -1
operation prior to analysis. Seawater samples contain nonvola- Collision Energy: Variable depending on analyte (Table 4)
tile salts; the elution from injection to 5 minutes after injection Exit Energy: 0
is diverted to waste in order to prevent mass spectrometer Low Mass Resolution 2: 14.0
sourcecontamination.Ifthereiscarry-overfromone
...