1、Designation: D8018 15Standard Test Method forDetermination of (Tri-n-butyl)-n-tetradecylphosphoniumchloride (TTPC) in Soil by Multiple Reaction MonitoringLiquid Chromatography/Mass Spectrometry (LC/MS/MS)1This standard is issued under the fixed designation D8018; the number immediately following the
2、 designation indicates the year oforiginal adoption 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 procedure covers the
3、 determination of (Tri-n-butyl)-n-tetradecylphosphonium chloride (TTPC) in a soilmatrix by extraction with acetone, filtration, dilution withwater, and analysis by liquid chromatography/tandem massspectrometry. TTPC is a biocide that strongly adsorbs to soils.2The sample extracts are prepared in a s
4、olution of 75 % acetoneand 25 % water because TTPC has an affinity for surfaces andparticles. The reporting range for this method is from 250 to10 000 ng/kg. This analyte is qualitatively and quantitativelydetermine by this method. This method adheres to multiplereaction monitoring (MRM) mass spectr
5、ometry.1.2 The Method Detection Limit (Note 1) (MDL) andReporting Range (Note 2) for the target analyte are listed inTable 1.NOTE 1The MDL is determined following the Code of FederalRegulations, 40 CFR Part 136, Appendix B, as a guide utilizing solventextraction of soil. Two-gram sample of Ottawa Sa
6、nd was utilized. Adetailed process determining the MDL is explained in the reference and isbeyond the scope of this standard to be explained here.NOTE 2Reporting range concentration is calculated from Table 2concentrations assuming a 50 L injection of the Level 1 calibrationstandard forTTPC, and the
7、 highest level calibration standard with a 20 mLfinal extract volume ofa2gsoil sample. Volume variations will changethe reporting limit and ranges.1.2.1 The reporting limit in this test method is the minimumvalue below which data are documented as non-detects. Ana-lyte detections between the method
8、detection limit and thereporting limit are estimated concentrations and are not re-ported following this test method. The reporting limit iscalculated from the concentration of the Level 1 calibrationstandard as shown in Table 2 for TTPC after taking intoaccounta2gsample weight and a final extract v
9、olume of 20mLin 75 % acetone/25 % water. The final extract volume is 20mL because a 15 mL volume of acetone is added to each soilsample and only the liquid layer after extraction is filteredleaving the solid behind followed by the addition of 5 mL ofwater to the acetone extract.1.3 UnitsThe values s
10、tated in SI units are to be regardedas standard. No other units of measurement are included 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
11、and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD5681 Terminology for
12、 Waste and Waste ManagementD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisE2554 Practice for Estimating and Monitoring the Uncer-tainty of Test Results of a Test Method Using ControlChart Techniques2.2 Other Documents:4EPA Publication SW-846 Test
13、 Methods for Evaluating SolidWaste, Physical/Chemical Methods40 CFR Part 136, Appendix B Definition and Procedure forthe Determination of the Method Detection Limit3. Terminology3.1 For determinations of terms used in this standard, referto Terminology D5681.1This test method is under the jurisdicti
14、on of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.01.06 onAnalytical Methods.Current edition approved Nov. 1, 2015. Published November 2015. DOI:10.1520/D8018-15.2More information on TTPC can be found at http:/ Biocide-BE-91.pdf(2014) and http:/iaspub.e
15、pa.gov/sor_internet/registry/substreg/searchandretrieve/advancedsearch/externalSearch.do?p_type=CASNO however, this test method is intended to be performancebased and alternative operating conditions can be used toperform this method provided data quality objectives areattained. Mention of trade nam
16、es or suppliers is not anendorsement of use, it is provided for informational purposesonly. Any apparatus, supply, standard, or reagent may be usedprovided that it is shown to be acceptable to meet theperformance criteria of the method.4.2 ForTTPC analysis, samples are shipped to the lab on iceand a
17、nalyzed within 14 days of collection. A sample (2 g) istransferred to a VOA vial, a TTPC spike solution is added toLaboratory Control and Matrix Spike samples before theaddition of acetone. An isotopically labeled TTPC surrogatecould be added at this point, presently requires a customsynthesis and s
18、hould be incorporated into this method by theuser if requested by the customer.5Then add 15 mL of acetoneand hand shake or vortex for one minute. The samples areallowed to settle, and are then filtered through a Nylonmembrane syringe driven filter unit6leaving the solids behind,5 mLofASTM Type 1 wat
19、er is added to the filtered extract andthen analyzed by LC/MS/MS.All concentrations reported, onlyto the reporting limit, using this method are based upon a dryweight basis.4.3 TTPC is identified by comparing the single reactionmonitoring (SRM) transition and its confirmatory SRM tran-sitions if cor
20、related to the known standard SRM transition(Table 3) and quantitated utilizing an external calibration. Thefinal report issued for each sample lists the concentration ofTTPC, if detected, or RL, if not detected, in ng/kg (Dry WeightBasis) and surrogate recovery, if available.5. Significance and Use
21、5.1 This test method has been developed by the US EPARegion 5 Chicago Regional Laboratory (CRL).5.2 TTPC may be used in various industrial and commercialproducts for use as a biocide. Products containing TTPC havebeen approved for controlling algal, bacterial, and fungalslimes in industrial water sy
22、stems.2TTPC should not bepersistent in water but may be deposited in sediments atconcentrations of concern. Hence, there is a need for quick,easy, and robust method to determine TTPC concentration attrace levels in various soil matrices for understanding thesources and concentration levels in affect
23、ed soils and sedi-ments.5.3 This method has been used to determine TTPC in sand,a commercial top soil and fourASTM reference soils (Table 4).6. Interferences6.1 All glassware is washed in hot water with detergent andrinsed in hot water followed by distilled water. The glasswareis then dried and heat
24、ed in an oven at 250C for 15 to 30minutes. All glassware is subsequently rinsed or sonicated, orboth, with acetone, n-propanol, or acetonitrile, or combinationsthereof.6.2 TTPC should not be a common contaminant found in alaboratory, unless involved in the analysis or matrices that5A custom synthesi
25、zed surrogate, TTPC (D29), may be an inexpensive viablesurrogate.6A Whatman Puradisc 25 NYL Disposable Filter unit (Diameter 25 mm,0.2 m Nylon membrane syringe driven filter unit has been found suitable for usefor this method, any filter unit may be used that meets the performance of thismethod may
26、be used. The use of PTFE, PVDF, and polypropylene filter unitsresulted in poor performance.TABLE 1 Method Detection Limit and Reporting RangeAAnalyte MDL (ng/kg) Reporting Range (ng/kg)TTPC 32.7 25010 000AAcronyms are defined in 3.3.D8018 152contain TTPC. TTPC has been found to continue to adhere to
27、glassware and syringes after routine glassware washing. Rins-ing glassware with acetone, n-propanol, or acetonitrile, or both,or even sonication, may be required to remove TTPC. All ofthe materials and supplies are routinely demonstrated to be freefrom interferences and TTPC by analyzing laboratory
28、blanksunder the same conditions as the samples. If found, measuresshould be taken to remove the contamination or data should bequalified, background subtraction of blank contamination is notallowed.6.3 All reagents and solvents should be pesticide residuepurity or higher to minimize interference pro
29、blems.6.4 Matrix interferences may be caused by contaminants inthe sample. The extent of matrix interferences can varyconsiderably depending on variations in the sample matrices.6.5 Automatic pipettes with polypropylene tips are usedwith this method. The use of glass syringes for standardspreparatio
30、n, spiking and calibrations generated erratic resultsand should be avoided. A thoroughly cleaned 20 mL hypoder-mic glass syringe with a nylon filter is used to filter the 20 mLsample extracts and has been shown to perform well whenfiltering these large volumes. Preparing small volumes ofsamples and
31、standards, like 1 mLcalibration standards, may beaffected by adhesion of TTPC to the syringe barrel or plunger.The use of PTFE, PVDF, and polypropylene filter unitsresulted in poor performance and low recoveries.NOTE 3The use of polypropylene disposable syringes to filter samplesand polypropylene LC
32、 vials with polyethylene caps have been shown toperform in the performance criteria of the method and may be used.7. Apparatus7.1 LC/MS/MS System:7.1.1 Liquid Chromatography System7A complete LCsystem is required in order to analyze samples, this shouldinclude a sample injection system, a solvent pu
33、mping system7A Waters Acquity UPLC H-Class System, or equivalent, has been foundsuitable for use.TABLE 2 Concentrations of Calibration Standards (ng/L)Concentrations(ng/L)LV1 LV2 LV3 LV4 LV5 LV6 LV7 LV8TTPC 25 50 100 200 400 600 800 1000TABLE 3 Retention Times, SRM Ions, and Analyte-Specific Mass Sp
34、ectrometer ParametersChemical Primary/ConfirmatorySRM Transition Cone (V) Collision (eV) Retention Time(minutes)Primary/Confirmatory SRMArea RatioTTPCPrimary(Quantitation)399.5 229.3 40 458.1NAFirst Confirmatory 399.5 75.9 40 46 0.92SecondConfirmatory399.5 343.5 40 40 3.02TABLE 4 Single-Laboratory R
35、ecovery Data in Six Soil TypesSampleOttawa Sand ASTM Frederick Sand ASTM Silt(2500 ng/kg spike) (2500 ng/kg spike) (2500 ng/kg spike)MB 1 RL RL RLMB 2 RL RL RLP Samplecompartment, 15C.11.2.3 Seal WashSolvent: 50 % methanol/50 % water;Time: 5 minutes.11.3 Mass Spectrometer Parameters:11.3.1 To acquir
36、e the maximum number of data points perSRM channel while maintaining adequate sensitivity, the tuneparameters may be optimized according to the instrument used.Each peak requires at least ten scans per peak for adequatequantitation. Variable parameters regarding retention times,SRM transitions, and
37、cone and collision energies are shown inTable 3. Mass spectrometer parameters used in the develop-ment of this test method are listed below:The instrument is set in the Electrospray positive source settingCapillary Voltage: 1 kVCone: Variable depending on analyteExtractor: 2 VoltsSource Temperature:
38、 150CDesolvation Gas Temperature: 500CDesolvation Gas Flow: 900 L/hrCone Gas Flow: 150 L/hrCollision Gas Flow: 0.15 mL/minLow Mass Resolution 1: 3High Mass Resolution 1: 14Ion Energy 1: 1Entrance Energy: 1Collision Energy: Variable depending on analyteExit Energy: 1Low Mass Resolution 2: 2.8High Mas
39、s Resolution 2: 14Ion Energy 2: 1Gain: 1.0Multiplier: 512.82Inter-Scan Delay: 0.003 seconds12. Calibration and Standardization12.1 The mass spectrometer shall be calibrated as permanufacturers specifications before analysis. Analytical val-ues satisfying test method criteria have been achieved using
40、 thefollowing procedures. Prepare all solutions in the lab usingClass A volumetric glassware.12.2 Calibration and StandardizationTo calibrate theinstrument, analyze eight calibration standards of the TTPCcompound prior to sample analysis as shown in Table 2.Calibration stock standard solution is pre
41、pared from the targetspike solution directly to ensure consistency. Stock standardSolution A containing the TTPC is prepared at Level 8concentration and aliquots of that solution are diluted toprepare Levels 1 through 7. The following steps will producestandards with the concentration values shown i
42、n Table 2. Theanalyst is responsible for recording initial component weightscarefully when working with pure materials and correctlycarrying the weights through the dilution calculations. At aminimum, five calibration levels are required when using alinear calibration curve and six calibration level
43、s are requiredwhen using a quadratic calibration curve.An initial eight pointcurve may be used to allow for the dropping of the lower levelcalibration points if the individual laboratorys instrumentcannot achieve low detection limits. This should allow for atleast a five or six point calibration cur
44、ve to be obtained. Noproblems were encountered while using the eight point cali-bration curve in developing this test method.12.2.1 Calibration stock standard SolutionA(Level 8, Table2) is prepared from the target spike solution directly to ensureconsistency. 500 L of TTPC Target Spike Solution (100
45、 g/L,12.7) is added to a 50 mLvolumetric flask and diluted to 50 mLwith 75:25 acetone:water. The preparation of the Level 8standard can be accomplished using appropriate volumes andconcentrations of stock solutions as per a particular laborato-rys standard procedure.12.2.2 Aliquots of Solution A are
46、 then diluted with 75:25acetone:water to prepare the desired calibration levels in 2 mLamber glass LC vials (Table 6). The calibration vials shall beused within 24 hours to ensure optimum results. Calibrationstandards are not filtered.12.2.3 Inject each standard and obtain its chromatogram.Anexterna
47、l calibration technique is used to monitor the primaryand confirmatory SRM transitions of TTPC. Calibration soft-ware is utilized to conduct the quantitation of the target analyteusing the primary SRM transition. The ratios of the primary/confirmatory SRM transitions area counts are given in Table 3
48、and will vary depending on the individual tuning conditions.The primary/confirmatory SRM transitions area ratio shall bewithin 35 % of the individual labs accepted primary/confirmatory SRM transitions area ratio. The primary SRMtransition of TTPC is used for quantitation and the confirma-tory SRM tr
49、ansitions for confirmation. This gives addedconfirmation by isolating the parent ion, forming three productions via fragmentation, and relating it to the retention time inthe calibration standard.12.2.4 Depending on sensitivity and matrix interferenceissues dependent on sample type, a confirmatory SRM transi-tion may be substituted as the primary SRM transition forTABLE 5 Gradient Conditions for Liquid ChromatographyTime (min) Flow (mL/min) Percent 95 % Water: 5 %AcetonitrilePercent
