OSAC 2022-S-0003

Standard Practice for the 

Analysis of Organic Gunshot 

Residue (OGSR) by Liquid

Chromatography-Mass 

Spectrometry (LC-MS)

Ignitable Liquids, Explosive, and Gunshot Residue Subcommittee

Chemistry: Trace Evidence Scientific Area Committee (SAC)

Organization of Scientific Area Committees (OSAC) for Forensic Science
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

2

Draft OSAC Proposed Standard

OSAC 2022-S-0003 Standard Practice 

for the Analysis of Organic Gunshot 

Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry 

(LC-MS)

Prepared by 

Subcommittee for Ignitable Liquids, Explosive, and Gunshot Residue

Version: 1.0 - OSAC Open Comment

October 2021

Disclaimer:

This OSAC Proposed Standard was written by the [insert subcommittee or other unit name] of 

the Organization of Scientific Area Committees (OSAC) for Forensic Science following a 

process that includes an open comment period. This Proposed Standard will be submitted to a 

standards developing organization and is subject to change. 

There may be references in an OSAC Proposed Standard to other publications under 

development by OSAC. The information in the Proposed Standard, and underlying concepts and 

methodologies, may be used by the forensic-science community before the completion of such 

companion publications.

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is not a recommendation or endorsement by the U.S. Government and does not imply that the 

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of proposed revisions of standards previously published by standards developing organizations 
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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(SDOs) to ensure that the published methods that practitioners employ are scientifically valid, 

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OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

1

1 Standard Practice for the Analysis of Organic Gunshot Residue (OGSR) by Liquid

2 Chromatography– Mass Spectrometry (GC-MS)

3

4 1. Scope

5 1.1. This practice covers the analysis of organic gunshot residue (OGSR) by liquid 

6 chromatography-mass spectrometry (LC-MS). This practice does not address the 

7 analysis of inorganic gunshot residue (IGSR) or primer gunshot residue (pGSR). 

8 1.2. This practice is intended for use by competent forensic science practitioners with the 

9 requisite formal education, discipline-specific training (see Practice E2917), and 

10 demonstrated competency to perform forensic casework. 

11 1.3. Units – The values stated in SI units are to be regarded as the standard, unless otherwise 

12 stated.

13 1.4. This practice does not purport to address all of the safety concerns, if any, associated 

14 with its use. It is the responsibility of the user of this standard to establish appropriate 

15 safety and health practices and determine the applicability of regulatory limitations prior 

16 to use.

17

18 2. Referenced Documents

19 2.1. ASTM Standards:

20 E1588 Standard Practice for Gunshot Residue Analysis by Scanning Electron 

21 Microscopy/Energy Dispersive X-ray Spectrometry.

22 E1732 Standard Terminology Relating to Forensic Science.

23 E2917 Standard Practice for Forensic Science Practitioner Training, Continuing Education, 

24 and Professional Development Programs. 

25 E2998 Standard Practice for Characterization and Classification of Smokeless Powders.

26 E2999 Standard Test Method for Analysis of Organic Compounds in Smokeless Powder 

27 by Gas Chromatography-Mass Spectrometry and Fourier Transform Infrared 

28 Spectroscopy

29 E3255 Standard Practice for Quality Assurance of Forensic Science Service Providers 

30 Performing Forensic Chemistry Analyses

31 WK56998 Standard Terminology Relating to the Examination of Explosives

32 WK72856 Standard Practice for the Collection and Preservation of Organic Gunshot 

33 Residue

34

35 3. Terminology

36 3.1. For definitions of terms that can assist in interpreting this practice, refer to Terminology 

37 E1732 and WK 56998.

38 3.2. Definitions of terms specific to this practice:

39 3.2.1. Inorganic GSR (IGSR), n – Gunshot residues from the primer, cartridge case, 

40 projectile (e.g., bullet or shot pellets), or the firearm that are typically identified 

41 using scanning electron microscope (E1588).
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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42 3.2.2. Organic GSR (OGSR), n – Gunshot residues from the propellant and the priming 

43 mixture that are organic (carbon-based).

44 3.2.3. Primer GSR (pGSR), n –Gunshot residues generating from the priming mixture that 

45 could be inorganic or organic.

46 3.2.4. Reference Sample, n – A solution containing known target OGSR compounds.

47

48 4. Significance and Use

49 4.1. Gunshot residue (GSR) examination is typically performed to determine if an individual 

50 was exposed to firearm discharge. GSR analysis has historically relied upon the detection 

51 of IGSR, as described in Practice E1588, which originates primarily from the ammunition 

52 primer (pGSR). OGSR analysis provides information which complements pGSR analysis 

53 [1]. 

54 4.2. OGSR originates from the combustion of the smokeless powder and the priming mixture 

55 following their ignition during the firearm discharge process. After a firearm has been 

56 discharged, the combined residue can be found on exposed surfaces in the vicinity of the 

57 fired weapon (e.g., hands, other exposed skin surfaces, hair, clothing, and other surfaces). 

58 OGSR can also be found in the cartridge case after firing and can be recovered to provide 

59 information about the constituents of the propellant or the priming mixture, or both. 

60 4.3. This practice is intended to be used in conjunction with a laboratory’s validated standard 

61 operating procedures.

62 4.4. This practice does not cover the interpretation or significance of the OGSR results. 

63 Laboratory specific criteria should be established and supported by the data obtained 

64 during method development and validation (E3255). 

65 4.5. Individual laboratory protocol will determine if IGSR/pGSR and OGSR will be analyzed 

66 from the same sample or separate samples [2,3].

67 4.6. The analysis of intact smokeless powder grains is beyond the scope of this standard 

68 practice (refer to Practice E2998 and Test Method E2999).

69

70 5. Apparatus

71 5.1. Liquid chromatograph (LC) - A liquid chromatograph (LC) that uses a reversed phase 

72 column and pump system providing a gradient of at least two solvents (refer to Appendix 

73 Table X1), coupled to a mass spectrometer with electrospray ionization (ESI) or 

74 atmospheric pressure chemical ionization (APCI) ion source working in positive and 

75 negative ion mode.

76 5.2. The use of a guard column is not required but is recommended to protect the analytical 

77 column

78 5.3. Mass Spectrometer (MS) - Mass analyzers with high resolution and mass accuracy, with 

mass measurements to the 4th 79 decimal place, are recommended (e.g., time-of-flight, 

80 quadrupole-time-of-flight, orbitrap, etc.).

81 5.4. Sonicator – For use when extracting OGSR components from sample items collected.

82 5.5. Centrifuge – Recommended for use after sonication of extract and capable to achieve a 

83 minimum of 4000 RPM. Disposable centrifuge tubes that safely fit the centrifuge device 

84 are required. 
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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85

86 6. Materials 

87 6.1. Purity of Solvents – LC-MS grade or higher.

88 6.2. Analytical Solvents – Acetone, acetonitrile, ethanol, isopropanol, methanol, water, or 

89 other appropriate solvents.

90 6.3. OGSR Standard(s) or Reference Materials – Certified reference materials are to be used. 

91 Individual reference materials or standards, or mixture thereof, may be used in place of a 

92 certified reference standard provided that they are verified before use.

93 6.3.1. The concentrations of standards or reference materials used must be above the limit 

94 of detection for the instrument to be used in analyzing samples.

95 6.4. Concentrations of OGSR compounds recovered in forensic samples can be as low as 25

96 ppb [4].

97 6.5. Internal Standard – Use of an internal standard is not required for qualitative identification 

98 of OGSR but can be used to evaluate system sensitivity and reproducibility.

99 6.6. Drying Gas – Nitrogen, air or other inert gas of a purity 99.95% or higher.

100 6.7. Filters – Single use disposable filters of a hydrophobic membrane construction are 

101 recommended for us to filter the extract prior to analysis. A filter membrane porosity of a 

102 0.4 μm or smaller is recommended. 

103

104 7. Procedure

105 7.1. Samples are submitted for OGSR analysis in one or more of the following forms: adhesive 

106 lifts, swabs and vacuum filters; refer to WK72856. 

107 7.2. Additional analyses can be performed on OGSR components that have been described 

108 elsewhere [WK GC-MS] [5, 6]. 

109 7.3. Preparation of OGSR Samples:

110 7.3.1. Extract swabs, vacuum filters, or adhesive lifts using a suitable organic solvent, 

111 such as methanol, acetonitrile, or a 20/80 ethanol:water mixture [7].

112 7.3.1.1. The volume of the solvent used must be sufficient to extract the entire surface 

113 or area of the sample collection item used.

114 7.3.2. Extract the sample by placing the collection item inside a new disposable vial of a 

115 minimum volume required to hold the entire item. Swabs can be folded to fit into 

116 the vial. Add a minimum volume of solvent required to submerge the entire item. 

117 7.3.3. Sonicate the vial with the item submerged in the solvent. Remove the extract and 

118 either filter or centrifuge the item to remove any solid particulates from the solution. 

119 7.3.4. Analyze the filtered or centrifuged extract directly or the extract can be 

120 concentrated if required for analysis. 

121 7.3.4.1. Concentrate the extract by evaporation down to the required volume using 

122 nitrogen gas or another dry gas.

7.3.5. Store extracts at 0 o 123 C or colder to maximize preservation, when the sample is not 

124 being analyzed. 

125 7.4. LC-MS analysis of OGSR extracts:
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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126 7.4.1. Common organic components of OGSR can be identified by LC-MS analysis.

127 7.4.2. The extract may be diluted, if required, to improve chromatography or mass spectral 

128 features.

129 7.4.3. The extract can be reconstituted using a suitable organic solvent to an appropriate 

130 volume if required for analysis (see section 6.2 [8]).

131 7.4.4. Suggested LC-MS parameters are listed in Appendix Table X1.

132 7.4.5. Validate this method on the laboratory’s instrument before using the method in 

133 casework (E3255).

134 NOTE: Modify LC conditions to ensure that each peak of the reference test sample has 

135 baseline resolution. If a peak is not observed in the total ion chromatogram, then view 

136 the extraction ion chromatogram for the base peak ion of the targeted molecule.

137 7.4.6. Prior to analyzing samples, the LC-MS should be tuned and calibrated per 

138 validation protocols or the manufacturers recommendations.

139 7.4.7. Table 1 lists the common target compounds and their key ions used to identify the 

140 presence of OGSR.

141 7.4.7.1. Data analysis is limited to the qualitative identification of the target 

142 compounds listed in Table 1. Parameters used for identification can be 

143 observed retention time(s), ions detected, their ion masses, and associated 

144 fragmentation pattern of the molecule, if any.

145 7.4.7.2. Each specific retention time is measured by analyzing a suitable reference 

146 material using the LC-MS system and method under the same instrumental 

147 conditions [8].

148 7.4.7.3. At this time, there are no satisfactory studies completed to determine the 

149 common background presence of OGSR. Therefore, quantitative analysis of 

150 OGSR by LC-MS is not recommended. 

151 7.4.7.3.1. It is the responsibility of each individual laboratory to verify any 

152 research study completed in their region concerning the background 

153 presence of OGSR [9, 10]. 

154 7.4.7.4. Interpretation of the presence or absence of target compounds in Table 1 is 

155 not covered in this standard practice (see Section 4.4).

156

157 TABLE 1: Typical OGSR related compounds and m/z of target ions found by LC-MS 

158 analysis

Target Compound Ionization Source 

and Mode

Exact Mass 

(m/z)

Commonly 

Observed Ion Ref.

Akardite II (AK II) ESI pos., APCI pos. 226.1106 [M+H]+[11]

2,4- and 2,6-dinitrotoluene

(2,4/2,6-DNT)

ESI neg. 182.0327 [M-H]-[5]

Diphenylamine (DPA) ESI pos., APCI pos. 169.0891 [M+H]+[5]

Ethyl centralite (EC) ESI pos., APCI pos. 268.1575 [M+H]+[5]

Methyl centralite (MC) ESI pos., APCI pos. 240.1262 [M+H]+[5]
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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2 and 4-nitrodiphenylamine 

(2/4-NDPA)

ESI pos,. APCI pos. 214.0742 [M+H]+[5]

Nitroglycerin (NG) ESI neg., APCI neg. 227.0024 [M+adduct]-

dependent upon 

LC conditions

[12]

N-nitrosodiphenylamine 

(N-NODPA)

ESI pos., APCI pos. 198.0793 [M+H]+[11]

Nitrotoluenes (NTs) ESI neg. 137.0476 [M-H]- [13]

2,4,6-trinitrotoluene (TNT) ESI neg. 227.0177 [M-H]-[2]

159

160 8. Identification of OGSR Compounds

161 8.1. The identification of a compound in an unknown sample should be based upon direct 

162 comparison with a known reference standard of the compound.

163 8.2. The unknown samples should be run on the same instrument using the same method as 

164 the known reference standard.

165 8.3. Identification criteria is provided for the liquid chromatography and mass spectrometry:

166 8.3.1. Liquid Chromatography

167 8.3.1.1. The retention time of the compound in the unknown sample should be within 

168 ± 0.1 minute of the reference compound.

169 8.3.2. Mass Spectrometry

170 8.3.2.1. The unknown and reference samples should have the same base peak and the 

171 same molecular ion, if present. The measured m/z value of the molecular ion 

172 should be within the instrument manufacturer’s tolerance (mass accuracy) of 

173 the theoretical value of the target compound.

174 8.3.2.1.1. NOTE: If a collisional induced dissociation is included, then 

175 comparison of the m/z values and relative abundances of fragment ions 

176 between the questioned and reference samples can be used in the 

177 identification of a compound.

178 8.3.2.2. Isotopic ions present in the reference spectrum shall be present in similar 

179 proportions in the unknown sample spectrum; low abundance ions (less than 

180 5% of the total spectral abundance) may be absent without precluding any 

181 identification.

182 8.3.2.3. Background subtraction may be necessary to remove any background 

183 contribution to the sample. 

184 8.3.2.4. There shall be no unexplained extraneous ions that have a significant 

185 abundance.

186

187 9. Quality Control

188 9.1. For minimum quality assurance protocols refer to Practice E3255.

189 9.2. Quality assurance protocols specific to this standard practice:

190 9.2.1. Analyze a quality control sample with questioned extracts.
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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191 9.2.1.1. The quality control sample should be analyzed, at minimum, at the 

192 beginning and the end of the analytical sequence on the instrument.

193 9.2.1.2. Quality control sample contains at least five compounds, as chosen by the 

194 individual laboratory, from the chemicals listed in Table 1.

195 NOTE: An example of a reference mixture is as follows: NG, EC, 2-NDPA, 

196 DPA and 2,4-DNT.

197 9.2.1.3. Establish protocols to ensure stability of the quality control sample.

198 9.2.1.4. Store quality control sample under appropriate conditions (see 7.2.4).

199 9.2.1.5. Replace the quality control sample when degradation is observed from the 

200 previous analysis of the sample. Examples of degradation include: the 

201 absence of peak(s), the presence of new peaks. The laboratory can also 

202 determine an expiration date for the quality control sample with questioned 

203 extracts. 

204 9.2.2. Analyze a method blank with questioned extracts.

205 9.2.2.1. Prepare a method blank using the same items, procedure(s), reagents, and 

206 conditions for analysis as the questioned extracts.

207 NOTE: if using a filter to prepare questioned samples for analysis, then a 

208 negative control of one filter per manufacturer lot should be collected and 

209 analyzed prior to sample preparation to ensure that the filter is not 

210 contaminated.

211 9.2.2.2. Analyze a solvent wash blank between each sample.

212

213 10. Documentation

214 10.1. Document the following, electronically or hard-copied:

215 10.1.1. LC-MS instrument settings and method parameters used for analysis.

216 10.1.2. Calibration and tuning of the instrument used for analysis.

217 10.1.3. Chromatograms of method blank(s), reference material(s), and questioned 

218 samples. Annotate peaks of interest with retention times.

219 10.1.4. Mass spectra of OGSR compounds identified and the associated material(s) used 

220 for comparison.

221 10.1.5. All analytical notes from the analysis including the details of sample preparation 

222 and instrument maintenance. 

223 10.1.6. Maintain reports in accordance with laboratory policy and E3255.

224

225 11. Keywords

226 11.1. OGSR; LC-MS.

227
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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228

229 12. References

230

231 [1] W. Feeney, C. Vander Pyl, S. Bell, T. Trejos. Trends in composition, collection, persistence, 

232 and analysis of IGSR and OGSR: A review. For Chem 19 (2020), 100250. 

233 [2] S. Benito, Z. Abrego, A. Sanchez, N. Unceta, M.A. Goicolea, R.J. Barrio, Characterization 

234 of organic gunshot residues in lead-free ammunition using a new sample collection device 

235 for liquid chromatography-quadrupole time-of-flight mass spectrometry, Forensic Sci Int 

236 246 (2015), 79-85. DOI: 10.1016/j.forsciint.2014.11.002.

237 [3] V. Redoute Minziere, D. Werner, D. Schneider, M. Manganelli, B. Jung, C. Weyermann, 

238 A.L. Gassner, Combined Collection and Analysis of Inorganic and Organic Gunshot 

239 Residues, J Forensic Sci 65 (2020), 1102-1113.

240 [4] W. Feeney, K. Menking-Hoggatt, C. Vander Pyl, C. E., Ott, S. Bell, L. Arroyo, T. Trejos, 

241 Detection of Organic and Inorganic Gunshot Residues from Hands using Complexing 

242 Agents and LC-MS/MS, Anal Methods, 13 (2021), 3024-3039. DOI: 10.1039/d1ay00778e.

243 [5] M. Morelato, A. Beavis, A. Ogle, P. Doble, P. Kirkbride, C. Roux, Screening of gunshot 

244 residues using desorption electrospray ionisation–mass spectrometry (DESI–MS), Forensic 

245 Sci Int 217 (2012), 101-106. DOI: 10.1016/j.forsciint.2011.10.030.

246 [6] E. Bernal Morales, A.L. Revilla Vázquez, Simultaneous determination of inorganic and 

247 organic gunshot residues by capillary electrophoresis, J Chromatogr A 1061 (2004), 225-

248 233. DOI: 10.1016/j.chroma.2004.10.083.

249 [7] A. Zeichner, B. Eldar, A Novel Method for Extraction and Analysis of Gunpowder Residues 

250 on Double-Side Adhesive Coated Stubs, J Forensic Sci 49 (2004), 1194-206.

251 [8] E. Goudsmits, G.P. Sharples, J.W. Birkett, Recent trends in organic gunshot residue 

252 analysis, TrAC Trends Anal Chem 74 (2015), 46-57. DOI: 10.1016/j.trac.2015.05.010.

253 [9] E. Goudsmits, G.P. Sharples, J.W. Birkett, Preliminary classification of characteristic 

254 organic gunshot residue compounds, Sci Justice 56 (2016), 421-425. DOI:

255 10.1016/j.scijus.2016.06.007.

256 [10] M. Manganelli, C. Weyermann, A.L. Gassner, Surveys of organic gunshot residue 

257 prevalence: Comparison between civilian and police populations, Forensic Sci Int 298 

258 (2019), 48-57. DOI: 10.1016/j.forsciint.2019.02.050.

259 [11] D. Laza, B. Nys, J.D. Kinder, A. Kirsch-De Mesmaeker, C. Moucheron, Development of a 

260 quantitative LC-MS/MS method for the analysis of common propellant powder stabilizers in 

261 gunshot residue, J Forensic Sci 52 (2007), 842-50. DOI: 10.1111/j.1556-4029.2007.00490.x.

262 [12] J.L. Thomas, D. Lincoln, B.R. McCord, Separation and detection of smokeless powder 

263 additives by ultra performance liquid chromatography with tandem mass spectrometry 

264 (UPLC/MS/MS), J Forensic Sci 58 (2013), 609-15. DOI: 10.1111/1556-4029.12096.

265 [13] Federal Criminal Police Office of Germany (BKA). Development of analytical methods for 

266 sensitive detection and identification of organic gunshot residues (OGSR) based on liquid 

267 chromatography-mass spectrometry (LC-MS) for routine casework. Project Number: 

268 HOME/2011/ISEC/AG/2504. E2017. Brussels, Belgium: Migration and Home Affairs, 

269 European Commission, 2017.

270
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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271 APPENDIX

272 (Non-mandatory Information)

273

274 X1. Instrumental Operation Parameters

275 X1.1 Suggested LC-MS Parameters 

276 X1.1.1 Examples of LC-MS instrumental methods, from literature, to analyzed OGSR 

277 compounds are provided below as a starting point for the laboratory validation process. 

278 These methods use a quadrupole-time of flight mass spectrometry (qTOFMS) [2,12] or 

279 triple-quadropole - linear iontrap hybrid mass detector (QTRAP) [3]; however, this 

280 method can be modified for any mass spectrometer system. 

281 X1.1.2 It is the responsibility of the individual laboratory to validate the method 

282 parameters prior to analyzing case samples. 

283 X1.1.3 Considering the individuality of each instrument, a gradient system and associated 

284 flow rate should be validated by the individual laboratory prior to analysis of case 

285 samples.

286

287 TABLE X1: Suggested LC-MS conditions from literature [2,3,12]

Parameter Ref. [2] Ref. [3] Ref. [3] Ref. [12]

LC column C18 100 mm x 3 

mm, 2.6 μm

C18 100 mm x 3 

mm, 2.6 μm

C18 100 mm x 3 

mm, 2.6 μm

Polar end-capped 

C18 150 mm x 1 

mm; 3 μm

Column 

Temperature

40 ± 0.8 °C 40 °C 40 °C 35 °C

Eluation 

Gradient

 Solvent A

 Solvent B

Water + 1 mmol 

Ammonium acetate

Methanol

Water + 0.1 % 

(v/v) formic acid

Acetonitrile + 0.1 

% (v/v) formic acid

Water + 2.5 mmol 

ammonium acetate

Methanol + 2.5 

mmol ammonium 

acetate

Water

Methanol

Flow Rate 

(mL/min)

0.1 - 0.3 0.25 0.40 0.05 – 0.15

Injection 

Amount

5 μl 5 μl 2 μl 3 μl

MS Ionization ESI ESI APCI ESI
OSAC 2022-S-0003 Standard Practice for the 

Analysis of Organic Gunshot Residue (OGSR) by Liquid

Chromatography-Mass Spectrometry (GC-MS)

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MS System Agilent 6530 

Accurate Mass 

QTOF with Jet 

Stream ionization 

source

AB Sciex QTRAP 

6500 +

Turbo V ESI 

ionization source

AB Sciex QTRAP 

6500 + 

Turbo V APCI 

ionization source

Bruker compact 

QqTOF

MS Conditions 

according to 

reference

Dry Gas: 10 L/min, 

300 °C

Nebulizer pressure: 

30 psi

Sheath Gas: 

Nitrogen, 11 

L/min, 300°C

Voltage: 5500 V

Desolvation 

temperature: 500°C

Curtain gas: 25 psi 

and a turbo gas of 

50 psi

Source 

temperature: 

137.5°C (NG), 

425°C (DNT)

Curtain gas: 30 psi 

(NG), 27.5 psi 

(DNT)

Ion source gas: 36 

psi (NG), 40 PSI 

(DNT)

End plate offset: 

500 V

Capillary voltage: 

4000 V

Nebulizer pressure: 

2.5 bar

Dry gas flow: 4 

L/min

Dry temperature: 

200°C

Ionization 

Mode

positive and 

negative

positive negative positive and 

negative

MS range 50 - 1000 Not provided Not provided Not provided

Target 

compounds

AK II, 2,4-DNT, 

DPA, N-NODPA, 

2-NDPA, 4-NDPA, 

EC, MC, TNT

AK II, DPA, NNODPA, 2-NDPA, 

4-NDPA, EC

NG, 2,4-DNT AK II, 2,4-DNT, 

2,6 DNT, DPA, NNODPA, 2-NDPA, 

4-NDPA, EC, NG

288