1、Designation: D 6363 98 (Reapproved 2003)e1Standard Test Method forDetermination of Hydrogen Peroxide and Combined OrganicPeroxides in Atmospheric Water Samples by PeroxidaseEnzyme Fluorescence Method1This standard is issued under the fixed designation D 6363; the number immediately following the des
2、ignation 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 (e) indicates an editorial change since the last revision or reapproval.e1NOTEEditorial changes were made throug
3、hout this test method in August 2003.1. Scope1.1 This test method covers the determination of hydroper-oxides, which include hydrogen peroxide (H2O2) and com-bined organic peroxides, in samples of atmospheric water bythe method of horseradish peroxidase derivatization and fluo-rescence analysis of t
4、he derived dimer.2,31.2 The range of applicable hydrogen peroxide concentra-tions was determined to be 0.6 - 176.0 3 106M fromindependent laboratory tests of the test method.1.3 The primary use of the test method is for hydrogenperoxide, but it may also be used to quantitate organichydroperoxides. D
5、eterminations of organic hydroperoxide con-centration levels up to 30 3 106M may be adequatelyobtained by calibration with hydrogen peroxide.2,3Whileorganic hydroperoxides have not been detected at significantconcentration levels in rain or cloud water, their presence maybe tested by operation of th
6、e test method with the addition ofcatalase for destruction of H2O23.1.4 Because of the instability of hydroperoxides in atmo-spheric water samples, proper sample collection, at-collectionderivatization, and stringent quality control are essential as-pects of the analytical process.1.5 This standard
7、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 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM S
8、tandards:4D 1129 Terminology Relating to WaterD 1193 Specification for Reagent WaterD 1356 Terminology Relating to Sampling and Analysis ofAtmospheresD 5012 Guide for Preparation of Materials Used for theCollection and Preservation of Atmospheric Wet Deposi-tionD 5111 Guide for Choosing Locations an
9、d Sampling Meth-ods to Monitor Atmospheric Deposition at Non-UrbanLocationsE 200 Standard Practice for Preparation, Standardization,and Storage of Standard and Reagent Solutions for Chemi-cal Analysis3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminologie
10、s D 1129 and D 1356 and GuideD 5111.3.2 Definitions of Terms Specific to This Standard:3.2.1 atmospheric water, nliquid or solid water sus-pended in the atmosphere or deposited from the atmosphere.Forms of atmospheric water include rain, snow, fog, cloudwater, dew, and frost.3.2.2 derivatization, nf
11、ormation of thep-hydroxyphenylacetic acidic dimer by combination ofp-hydroxyphenylacetic acid, horseradish peroxidase reagent,and hydroperoxide(s). Also the procedure of addition of thederivatizing reagent to samples.3.2.3 hydroperoxides, nhydrogen peroxide and organicperoxides dissolved in water.1T
12、his guide is under the jurisdiction of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.03 on Ambient Atmospheresand Source Emissions.Current edition approved August 10, 2003. Published October 2003. Originallyapproved in 1998. Last previous edition approved in 1
13、998 as D 6363 - 98.2Lazrus, A. L., Kok, G. L., Gitlin, S. N., and Lind, J. A., “AutomatedFluorometric Method for Hydrogen Peroxide in Atmospheric Precipitation,” Anal.Chem., 57, 1985, pp. 917922.3Kok, G. L., Thompson, K., and Lazrus,A. L., “Derivatization Technique for theDetermination of Peroxides
14、in Precipitation,” Anal. Chem., 58, 1986, pp.11921194.4For 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.1Copyri
15、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.4 intrinsic hydroperoxides, nhydroperoxides con-tained in reagent water used for the method.3.2.5 post-derivatization, naddition of the derivatizingreagent to the sample after collection.3
16、.2.6 pre-derivatization, naddition of the derivatizing re-agent to the sample collection container prior to samplecollection.3.2.7 systems blank, na field blank of reagent water that issubjected to a similar or identical environment and derivatiza-tion time as a collected atmospheric water sample.3.
17、2.8 systems standard, na H2O2calibration standardsolution subjected to a similar or identical environment andderivatization time as a collected atmospheric water sample.4. Summary of Test Method4.1 The peroxidase enzyme fluorescence method is based onthe reaction of hydroperoxides, horseradish perox
18、idase, andp-hydroxyphenylacetic (PHOPAA) acid, forming a fluorescentdimer of the latter. This dimer is detected using a fluorometrictechnique, and the hydroperoxides are quantified by calibrationwith hydrogen peroxide. The formation of the dimer (deriva-tization) shall be accomplished soon after sam
19、ple collection tominimize H2O2decay. In addition, strict quality assurancepractices are part of the method, including use of systemsstandards and systems blanks to estimate hydroperoxide lossand to assess derivatizing solution effectiveness.5. Significance and Use5.1 Hydrogen peroxide (formed photoc
20、hemically in theatmosphere) is a primary oxidizer of dissolved sulfur dioxide inatmospheric water. Detection of H2O2in atmospheric water isuseful for inferring gas-phase H2O2concentrations and forassessing the relative importance of various acidifying mecha-nisms under specific atmospheric condition
21、s.5.2 Hydroperoxides in samples to be analyzed are unstablein water and can decay rapidly due to bacterial action orchemical reaction with other constituents. The test methodincludes procedures for sample derivatization and methods forestimating and correcting for hydroperoxide decay.6. Interference
22、s6.1 The derivatizing reagent is formulated to counteract theeffects of the following potentially interfering species.6.2 Hydroxymethane Sulfonate (HMSA)The addition offormaldehyde (HCHO) to the derivatizing reagent will sup-press the negative interference of HMSA. In the absence ofadded HCHO, the P
23、HOPAA dimer in a derivatized simulatedrain sample, containing 1.2 3 105MH2O2and 1.0 3 104MHMSA, displayed a fluorescence signal 5 % lower than thatobserved when HCHO was added to the derivatizing reagent.36.3 Trace Transition Metals and Common Ionic Compo-nents of Atmospheric Water (Sodium, Ammonium
24、, Hydrogen,Sulfate, Nitrate, Chloride, Formate)Potential interference bytransition metals is overcome by the formation of ethylenedi-aminetetraacetic acid (EDTA) complexes. Tests of simulatedrain samples containing transition metals and common ioniccomponents of precipitation have demonstrated both
25、the gen-eral applicability of this test method to samples containingcommon contaminants and the stability of derivatized solutionsstored at 4C for more than five days.37. Apparatus7.1 Flow System, consisting of the following:7.1.1 Automatic sampler or injection valve.7.1.2 Automated wet chemistry (p
26、eristaltic) pump.7.1.3 Reagent manifold.7.1.4 Mixing coil; 5-turn, 2-mm inner diameter.7.1.5 Fluorometer; excitation at 320 nm and measurementof the fluorescence signal at 400 nm; flow-through fluorescencecell.7.1.6 Recorder.7.2 Sample and Standards ContainersAll containers usedfor sample collection
27、 and sample transport, for storage andanalysis of samples and standards, and for reagents should behigh density polyethylene, TFE-fluorocarbon, or borosilicateglass, cleaned in accordance with procedures established foranalyses of common inorganic ions (see Guide D 5012).7.3 Pipettes with Disposable
28、 TipsSolution preparationand sample fixing operations are generally conducted usingautomatic pipettes. Solution volumes delivered by these de-vices should be verified to confirm consistent and accurateperformance.57.4 Reagent BottlesAll containers used for the prepara-tion and storage of derivatizin
29、g and other reagent solutionsshall be dedicated for hydroperoxides. Containers for solutionsof catalase shall not be used for non-catalase solutions.8. Reagents and Materials8.1 Purity of ReagentsUnless otherwise noted, reagentgrade chemicals shall be used.68.2 Purity of WaterUnless otherwise indica
30、ted, referencesto water shall be understood to mean reagent water as definedby Type I of Specification D 1193, with the added stipulationthat the total organic carbon content be less than 20 g/L. AType I water system equipped with an organic extractioncartridge and a 0.2 m filter is an acceptable wa
31、ter source.Water to be used for reagents, standard solutions, and analyti-cal rinsing should be stored in borosilicate glass.8.3 Catalase Enzyme (1.7 3 106units/mL)7The enzymecatalase may be used for the destruction of H2O2in atmo-spheric water samples. Its addition to the sample beforeaddition of t
32、he derivatizing reagent removes H2O2, but organichydroperoxides are preserved. Subsequent addition of thederivatizing reagent results in dimer formation by way ofreaction with peroxides other than H2O2. Results of analyses of5Schwartz, L.M., “Calibration of Pipets: A Statistical View,” Analytical Ch
33、em-istry, Vol. 61, 1989, pp. 10801083.6Reagent 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,
34、U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.7Catalase enzyme, 1.7 3 106units/mL, has been found satisfactory for thispurpose. Available through Sigma Chemical Co., P.O. Box 14508, St. Louis, MO63178.D 6363 98 (2003)e12catal
35、ase-treated samples may be compared with the measure-ment of peroxides in samples without catalase to determineH2O2by difference.8.3.1 Catalase,1+49Dilute 1 mL of catalase enzyme toa final volume of 50 mL with water. Before pipetting theconcentrated solution, ensure that all the solid material iscom
36、pletely suspended by shaking or stirring the bottle ofconcentrate. Allow the dilute solution to stand at least 4 hbefore use. The solution can be stored for up to 48 h at 4C.8.4 Derivatizing Reagent, ConcentratedDissolve 12.11 gof Tris(hydroxymethyl)aminomethane, 0.38 g of EDTA, tetra-sodium salt, 4
37、.57 g of PHOPAA, 300 units of horseradishperoxidase, and 1 mL concentrated hydrochloric acid in water,and dilute to 200 mL in a volumetric flask. The final pH of thissolution should be 9.0. If greater than 9.5 or less than 8.5,remake. Prepare every four days and store at 4C. Measure-ment of peroxide
38、s in aqueous atmospheric samples is based onthe fluorescence of the PHOPAA dimer produced by reactionof hydroperoxides with PHOPAA. The fluorescence of samplesderivatized at the time of collection provides a measure of totalhydroperoxide (organic and H2O2) content of the sample.8.4.1 Derivatizing Re
39、agent,4+96Dilute 4.0 mL of theconcentrated derivatizing reagent to 100 mL with water.Prepare daily as needed, and keep tightly sealed at 4C.NOTE 1The dilute derivatizing reagent is normally added to samplesto be analyzed in the reagent:sample ratio of 1:1. Other concentrations ofdilute derivatizing
40、reagent may be used as long as the final ratio enteringthe analytical system is 1:1. Under special circumstances, other ratios maybe dictated by sampling conditions (see 10.6 and 10.7).8.5 Hydrochloric Acid (HCl), (1 M)Add 8.3 mL concen-trated HCl to water in a volumetric flask and dilute to 100 mL.
41、8.6 Peroxide Solution, Standard Stock (1 %)Dilute com-mercially available (pharmaceutical grade is acceptable) H2O2solution (30 %) approximately1+29with water in a volu-metric flask. Add sodium stannate (Na2SnO3) to a concentra-tion of 10.65 mg/L and store at 4C, and store in a borosilicateglass bot
42、tle. Determine the peroxide concentration by titrationwith standard permanganate solution (see 11.2) approximately24 h after preparation. Update the concentration determinationby titration at one month intervals.8.6.1 Peroxide Solution, 1 + 199Dilute 500 L of thestandard stock (1 %) solution to 100
43、mL with water in avolumetric flask. The approximate H2O2concentration of theresulting solution is 1500 M (50 mg/L). Calibration standardsare prepared immediately before sample analysis by dilutingaliquots of this solution (see 11.3).8.6.2 Peroxide Solution, Systems BlankWater combinedwith dilute der
44、ivatizing reagent to the ratio 1:1. Prepare inperoxide calibration standard vials or in sample collectioncontainers, depending on the derivatization method (see Sec-tion 10).8.6.3 Peroxide Solution, Systems StandardSee 11.3. Pre-pare in vials used for peroxide calibration standards or insample colle
45、ction containers, depending on the derivatizationmethod (see Section 10).8.7 Potassium Permanganate (KMnO4) Solution, Standard(0.01 M)Dissolve 1.58 g KMnO4in 100 mLwater, and dilutethe solution with water to 1 L. Seal tightly, and store in anamber borosilicate glass bottle in the dark. Standardize f
46、ollow-ing the procedure in Practice E 200, Sections 6468; adjustchemical proportions according to 9.1 of that Practice.8.8 Sodium Hydroxide (NaOH) (0.1 M)Dissolve 4.0 g ofsodium hydroxide in water and dilute to 1 L. Prepare weekly.8.9 Sulfuric Acid (H2SO4), 5 % (3.6 M)Add 5 mL con-centrated H2SO4to
47、water in a volumetric flask, and dilute to100 mL.9. Sample Collection9.1 Select sampling locations and sampling methods inaccordance with Guide D 5111. Additional considerations spe-cific to sampling for aqueous-phase hydrogen peroxide areprovided in 9.3 and 9.4.9.2 Methods of preparation of sample
48、containers for collec-tion, transport, and storage shall be those detailed in GuideD 5012 under inorganic ionic species (see 8.1 and 8.2 of GuideD 5012).9.3 Control procedures designed to ensure sample integrityin the field (see Section 10) are difficult to perform adequatelyif buckets or other high
49、 atmospheric-exposure collectors areused. Therefore, sampling for rain should be conducted usingfunnel-and-bottle type, or narrow-necked, collectors.9.4 The requirements for controlled derivatization of hydro-peroxides and timely analysis (see Section 10) dictate thatsampling for wet deposition be conducted on a daily or morefrequent basis.10. Derivatization10.1 The following procedures shall be in addition to thosespecified for preservation of inorganic anions and cations inGuide D 5012 (see Table 1 of Guide D 5012).10.2 Hydroperoxides di
