1、Designation: D7730 17Standard Test Method forDetermination of Dioctyl Sulfosuccinate in Sea Water byLiquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)1This standard is issued under the fixed designation D7730; the number immediately following the designation indicates the year oforiginal adop
2、tion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of dioctylsulfosuccinate (DOSS
3、) in sea water by direct injection usingliquid chromatography (LC) and detection with tandem massspectrometry (MS/MS). This analyte is qualitatively and quan-titatively determined by this test method. This test methodadheres to selected reaction monitoring (SRM) mass spectrom-etry.1.2 The detection
4、verification level (DVL) and reportingrange for DOSS are listed in Table 1.1.2.1 The DVL is required to be at a concentration at least3 times below the reporting limit (RL) and have a signal/noiseratio greater than 3:1. Fig. 1 and Fig. 2 display the signal/noiseratio of the selected reaction monitor
5、ing (SRM) transition.1.2.2 The reporting limit is the concentration of the Level 1calibration standard as shown in Table 5 for DOSS, taking intoaccount the 50 % sample preparation dilution factor.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are inclu
6、ded in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limi
7、tations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization
8、 TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water2.2 Other Standards:3EPA Publicatio
9、n SW-846 Test Methods for Evaluating SolidWaste, Physical/Chemical Methods3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer toTerminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 detection verification level, DVL, na concentrationthat has
10、 a signal/noise ratio greater than 3:1 and is at least 3times below the reporting limit (RL).3.2.2 reporting limit, RL, nthe concentration of thelowest-level calibration standard used for quantification.3.3 Abbreviations:3.3.1 mMmillimolar,1103moles/L3.3.2 NAno addition3.3.3 NDnon-detect3.3.4 ppbpar
11、ts per billion, g/L4. Summary of Test Method4.1 This is a performance-based method, and modificationsare allowed to improve performance.4.2 For DOSS analysis, samples are shipped to the labbetween 0C and 6C and analyzed within 5 days. In the lab,the entire collected 20-mL sample is spiked with surro
12、gate,1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved Dec. 15, 2017. Published January 2018. Originallyapproved in 2011. Last previous editi
13、on approved in 2011 as D7730 11. DOI:10.1520/D7730-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Availa
14、ble from National Technical Information Service (NTIS), 5301 ShawneeRd., Alexandria, VA 22312, http:/www.ntis.gov.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationa
15、lly recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1ammonium formate buffer solution and brought to a volum
16、e of40 mL with acetonitrile. This prepared sample is then filteredusing a syringe driven filter unit, and analyzed by LC/MS/MS.If visible oil is present, the prepared sample is allowed to settleresulting in an oil layer at the top of the 40-mL solution. Aportion of the aqueous (bottom) layer is filt
17、ered, leaving the oillayer behind, through a syringe driven filter assembly andanalyzed by LC/MS/MS.4.3 DOSS and DOSS surrogate are quantitated by retentiontime and one SRM transition. The final report issued for eachsample lists the concentration of DOSS and the surrogaterecovery.5. Significance an
18、d Use5.1 DOSS is an anionic detergent that is approved by theUnited States Food and Drug Administration (U.S. FDA) andis used widely as a laxative, emulsifying, solubilizing, anddispersing agent, and is used in the cosmetic industry.4DOSSmay also be used as a dispersing agent to treat oil. DOSS mayb
19、e released into the environment at levels that may be harmfulto aquatic life. The U.S. EPAaquatic life benchmark for DOSSis 40 ppb.55.2 This test method has been investigated for use withreagent and sea water.6. Interferences6.1 Method interferences may be caused by contaminants insolvents, reagents
20、, glassware, and other apparatus producingdiscrete artifacts or elevated baselines. All of these materialsare demonstrated to be free from interferences by analyzinglaboratory reagent blanks under the same conditions assamples.6.2 All glassware is washed in hot water with detergent andrinsed in hot
21、water followed by distilled water. The glasswareis then dried and heated in an oven at 250C for 15 to 30minutes. All glassware is subsequently cleaned with methanolor 50 % acetonitrile/50 % water, or both.6.3 System contamination and surface binding are problem-atic as DOSS is a surface active compo
22、und. It is important tothoroughly rinse sample containers with organic solvent toaccurately measure DOSS concentrations. Thorough rinsing ofall lab equipment is necessary to reduce contamination. Care-fully analyze blanks to ensure that the method minimizesDOSS carryover.6.4 All reagents and solvent
23、s should be pesticide residuepurity or higher to minimize interference problems.6.5 Matrix interferences may be caused by contaminants inthe sample. The extent of matrix interferences can varyconsiderably from sample source depending on variations ofthe sample matrix.6.6 Sulfonate filters contribute
24、 significantly to backgroundinterference and should be avoided for this standard. Inaddition to sample filtration, sulfonate filters may be present inwater purification systems.7. Apparatus7.1 LC/MS/MS System:7.1.1 Liquid Chromatography SystemA complete LC sys-tem is needed in order to analyze sampl
25、es.6Any system that iscapable of performing at the flows, pressures, controlledtemperatures, sample volumes, and requirements of the stan-dard may be used.7.1.2 Analytical ColumnWaters Atlantis dC18,72.1 150mm, 3-m particle size was used to develop this test method.Any column that achieves baseline
26、resolution of these analytesmay be used. Baseline resolution simplifies data analysis andcan reduce the chance of ion suppression, leading to higherlimits of detection. The retention times and order of elutionmay change depending on the column used and need to bemonitored.7.1.3 Tandem Mass Spectrome
27、ter SystemA MS/MS sys-tem capable of MRM analysis.8Any system that is capable ofperforming at the requirements in this standard may be used.7.2 Filtration Device:7.2.1 Hypodermic syringeA Lock Tip Glass Syringe ca-pable of holding a Millex HVSyringe Driven Filter Unit PVDF0.22 m,9,10or similar, may
28、be used.7.2.1.1 A Lock Tip Glass Syringe was used in this testmethod.7.2.2 FilterMillex HV Syringe Driven Filter Unit PVDF0.22 m, or similar, may be used.8. Reagents and Materials8.1 Purity of ReagentsHigh Performance Liquid Chroma-tography (HPLC) pesticide residue analysis and spectropho-tometry gr
29、ade chemicals shall be used in all tests. Unlessindicated otherwise, it is intended that all reagents shallconform to the Committee on Analytical Reagents of the4Code of Federal RegulationsTitle 21: Food and Drugs, Part 172, Availablefrom U.S. Government Printing Office, Superintendent of Documents,
30、 732 N.Capitol St., NW, Washington, DC 20401-0001, http:/www.access.gpo.gov.5Additional information about DOSS is available at http:/www.epa.gov/bpspill/dispersant-methods.html (2010)6A Waters ACQUITY UltraPerformance Liquid Chromatography (UPLC)System, a trademark of the Waters Corporation, Milford
31、, MA, was used to developthis test method.All parameters in this test method are based on this system and mayvary depending on your instrument.7The Waters Atlantis dC18 is a trademark of the Waters Corporation, Milford,MA.8A Waters Quattro Premier XE tandem quadrupole mass spectrometer, atrademark o
32、f the Waters Corporation, Milford, MA, was used to develop this testmethod. All parameters in this test method are based on this system and may varydepending on your instrument.9The sole source of supply of the Millex HV Syringe Driven Filter Unit PVDF0.45 m known to the committee at this time is Mi
33、llipore Corporation, Catalog #SLHV033NS. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.10Millex is a trademark of M
34、erck KGAA, Darmstadt, Germany.TABLE 1 Detection Verification Level (DVL) and Reporting RangeAnalyteDVL(g/L)Reporting Range(g/L)DOSS 3 20400D7730 172FIG. 1 Detection Verification Level Signal/Noise RatioFIG. 2 Reporting Level Signal/Noise RatioD7730 173American Chemical Society.11Other reagent grades
35、 may beused provided they are first determined to be of sufficientlyhigh purity to permit their use without affecting the accuracy ofthe measurements.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Type 1 of Specification D1193
36、. It must be demonstrated thatthis water does not contain contaminants at concentrationssufficient to interfere with the analysis.8.3 GasesUltrapure nitrogen and argon.8.4 Acetonitrile (CH3CN, CAS # 75-05-8).8.5 Methanol (CAS # 67-56-1).8.6 Ammonium formate (NH4CO2H, CAS # 540-69-2).8.7 2-Propanol (
37、CAS # 67-63-0).8.8 Dioctyl sulfosuccinate (DOSS) purchased as the sodiumsalt (CAS # 577-11-7).8.9 Dioctyl sulfosuccinate-13C4, (bis(2-ethylhexyl) sulfos-uccinate (Fumaric acid-13C4) sodium salt (Unlabeled CAS #577-11-7), (Optional Surrogate, custom synthesis).8.10 Dioctyl sulfosuccinate-D34(DOSS-D34
38、), bis(2-ethylhexyl-D17) sulfosuccinate sodium salt (Unlabeled CAS #577-11-7).9. Hazards9.1 Normal laboratory safety applies to this test method.Analysts should wear safety glasses, gloves, and lab coatswhen working in the lab. Analysts should review the MaterialSafety Data Sheets (MSDS) for all rea
39、gents used in this testmethod.10. Sampling10.1 Sampling and PreservationGrab samples should becollected in 20-mL pre-cleaned glass vials with TFE-fluorocarbonlined septa caps demonstrated to be free ofinterferences. This test method is based on a 20-mL samplesize per analysis. Each sample should be
40、collected in duplicateand a quadruplicate sample must be included with each samplebatch of 10 for MS/MSD quality control analyses. Storesamples between 0C and 6C from the time of collection untilanalysis. Analyze the sample within five days of collection.10.2 DOSS is surface active. The surface acti
41、vity results inDOSS adhering to many materials. Sampling techniques thatexpose samples to materials other than the sample containermay reduce DOSS concentration in samples. Sampling tech-niques such as peristaltic pumping expose the sample to largesurface areas compared to sample volume. Grab sampli
42、ngtechniques should be used. Transferring of sample from aninitial collection device to sampling vial may result in biasedlow DOSS concentrations and must be avoided.11. Preparation of LC/MS/MS11.1 LC Chromatograph Operating Conditions:611.1.1 Injection volumes of all calibration standards andsample
43、s are made at 50-L volume using a full loop injection.“Full loop” mode is the preferred technique when performingquantitative analyses. Multiple blank samples should be ana-lyzed at the beginning of a run to remove residual DOSS fromthe system. The first sample analyzed after the calibrationcurve is
44、 a blank to ensure there is negligible (less than theDVL) DOSS carry-over. The gradient conditions for the liquidchromatograph are shown in Table 2. Divert the column flowaway from the electrospray source for 0 to 5 minutes afterinjection. Flow diversion to waste may be done using the massspectromet
45、er divert valve, divert tubing configurations varyfrom manual injection. Test the divert valve configuration andoperation prior to analysis. Seawater samples contain nonvola-tile salts; the elution from injection to 5 minutes after injectionis diverted to waste in order to prevent mass spectrometers
46、ource contamination. If there is carry-over from one sample toanother, greater than half the reporting limit, the initial per-centage of acetonitrile should be raised as shown in Table 3 totry and remove the carry-over. This will shorten the elutiontime of DOSS approximately 1 minute; therefore it i
47、s necessaryreduce the flow diversion and adjust the MRM time. Increasingthe initial acetonitrile gradient concentration does not increasethe DVL or reporting limit.11.2 LC Sample Manager Conditions:11.2.1 Wash SolventsWeak wash is 4.0 mL of 50 %water/50 % acetonitrile. Strong wash is 2.0 mL of 60 %a
48、cetonitrile/40 % 2-propanol. The strong wash solvent isneeded to eliminate carry-over between injections of DOSSsamples. The weak wash is used to remove the strong washsolvent. Instrument manufacturer specifications should be fol-lowed in order to eliminate sample carry-over.11.2.2 TemperaturesColum
49、n, 35C; sample compartment,15C.11.2.3 Seal WashSolvent: 50 % acetonitrile/50 % water;time: 2 minutes.11Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 2 Gradient Conditions for DOSS Liquid ChromatographyT
