Table 2.
Carboxylic acid peaks found in pooled rat urine and identification results.
| Peak | BAMP | HAMP | Identificationb | |||||
|---|---|---|---|---|---|---|---|---|
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| Tr (min) | m/z | Int.a (%) | Tr (min) | m/z | Int.a (%) | Mr | Compound | |
| 1 | 11.81 | 235.19(+1) | 1.11 | 12.7 | 264.21(+1) | 0.78 | 88.21 | U |
| 1 | 11.81 | 320.46(+1) | 0.71 | 12.7 | 348.47(+1) | 0.5 | 173.17 | n-acetylleucine (R) |
| 2 | 13.67 | 299.37(+1) | 0.49 | 14.52 | 327.42(+1) | 0.35 | 152.12 | U |
| 3 | 13.76 | 313.35(+1) | 0.88 | 14.72 | 341.39(+1) | 0.63 | 166.09 | U |
| 4 | 14.99 | 204.78(+3) | 0.88 | 16.5 | 232.79(+3) | 0.63 | 172.47 | U |
| 4 | 14.99 | 254.35(+1) | 0.88 | 16.5 | 282.36(+1) | 0.63 | 107.06 | U |
| 4 | 14.99 | 303.30(+1) | 1.28 | 16.5 | 331.33(+1) | 0.91 | 156.03 | furan-2,5-dicarboxylic acid, mono- (R) |
| 4 | 14.99 | 278.40(+2) | 3.99 | 16.5 | 306.87(+2) | 2.83 | 263.14 | U |
| 5 | 15.08 | 270.33(+1) | 0.88 | 16.8 | 298.33(+1) | 0.63 | 123.03 | Nicotinic acid (S) |
| 6 | 15.2 | 213.37(+2) | 0.8 | 17 | 241.38(+2) | 0.56 | 132.16 | oxaloacetic acid, di- (S) |
| 6 | 15.22 | 211.35(+1) | 0.26 | 17.08 | 239.37(+1) | 0.18 | 64.07 | U |
| 7 | 15.38 | 191.31(+1) | 3.98 | 17.22 | 219.35(+1) | 2.82 | 44.05 | U |
| 7 | 15.38 | 299.37(+1) | 4.86 | 17.23 | 327.32(+1) | 3.45 | 152.02 | U |
| 7 | 15.45 | 274.32(+1) | 1.46 | 17.4 | 302.40(+1) | 1.03 | 127.1 | δ-Piperideine-6-L-carboxylate |
| δ-Piperideine-2-carboxylate (L) | ||||||||
| 8 | 16.25 | 192.36(+2) | 0.32 | 18.08 | 220.40(+2) | 0.66 | 90.2 | oxalic acid (S) |
| 8 | 16.27 | 203.84(+2) | 0.48 | 18.08 | 231.87(+2) | 0.34 | 113.14 | U |
| 9 | 16.68 | 206.36(+2) | 2.37 | 18.48 | 234.37(+2) | 1.68 | 118.14 | succinic aicd,di- (S) |
| 10 | 17.05 | 234.34(+2) | 4.87 | 18.82 | 262.34(+2) | 3.45 | 174.08 | citric acid, di-,-H2O (S) |
| 10 | 17.04 | 214.37(+2 | 0.38 | 18.92 | 242.39(+2) | 0.27 | 134.18 | malic acid, di- (S) |
| 11 | 17.27 | 220.38(+2) | 0.27 | 19.09 | 248.38(+2) | 0.19 | 146.16 | α-ketoglutaric acid, di- (S) |
| 11 | 17.27 | 234.34(+2) | 1.6 | 19.14 | 262.36(+2) | 1.01 | 174.12 | iso-citric acid, di-,-H2O (S) |
| 11 | 17.27 | 225.37(+2) | 1.33 | 19.17 | 253.35(+2) | 0.94 | 156.1 | furan-2,5-dicarboxylic acid, di- (R) |
| 11 | 17.3 | 255.25(+2) | 1.16 | 19.34 | 283.25(+2) | 0.82 | 215.9 | 5-Oxopent-3-ene-1,2,5-tricarboxylate |
| 5-Carboxymethyl-2-hydroxymuconate (L) | ||||||||
| 12 | 17.75 | 269.85(+2) | 0.76 | 19.45 | 297.86(+2) | 0.54 | 245.12 | U |
| 13 | 18.05 | 250.84(+2) | 1.59 | 19.76 | 278.88(+2) | 1.12 | 207.16 | methylcitric acid, di- (S) |
| 13 | 18.07 | 220.57(+2) | 0.44 | 19.8 | 248.38(+2) | 0.31 | 146.16 | adipic acid, di-, (S) |
| 13 | 18.1 | 207.38(+1) | 1.11 | 19.84 | 235.31(+1) | 0.78 | 60.01 | U |
| 13 | 18.1 | 243.33(+2) | 5.13 | 19.92 | 271.32(+2) | 3.64 | 192.08 | citric acid, di-, (S) |
| 14 | 18.28 | 234.33(+2) | 0.8 | 20.23 | 262.36(+2) | 0.57 | 174.12 | suberic acid, di-, (S) |
| 14 | 18.3 | 257.39(+2) | 0.35 | 20.52 | 285.40(+2) | 0.25 | 220.02 | 3-hydroxy-3-(carboxymethyl)-adipic acid, di-, (R) |
| 14 | 18.32 | 243.35(+2) | 0.71 | 20.58 | 271.34(+2) | 0.5 | 192.08 | isocitric acid, di-, (S) |
| 14 | 18.37 | 220.39(+2) | 0.42 | 20.59 | 248.37(+2) | 0.29 | 146.16 | 3-methylglutaric acid, di-, (S) |
| 15 | 18.7 | 193.31(+1) | 5.77 | 20.88 | 221.32(+1) | 4.09 | 46.02 | formic acid, (S) |
| 16 | 19.55 | 208.31(+1) | 4.32 | 21.72 | 236.32(+1) | 3.06 | 61.02 | carbonic acid, (S) |
| 17 | 20.27 | 221.37(+1) | 0.27 | 22.3 | 249.37(+1) | 0.19 | 74.07 | glyoxylic acid, (S) |
| 17 | 20.18 | 207.31(+1) | 4.43 | 22.33 | 235.33(+1) | 3.14 | 60.03 | acetic acid, (S) |
| 18 | 20.45 | 247.32(+1) | 3.07 | 22.83 | 275.33(+1) | 2.17 | artifact c | |
| 19 | 21 | 221.37(+1) | 1.26 | 23.15 | 249.38(+1) | 0.89 | 74.08 | propionic acid, (S) |
| 20 | 21.5 | 261.33(+1) | 0.46 | 23.6 | 289.36(+1) | 0.32 | 114.06 | 2-Hydroxy-2,4-pentadienoate |
| cis-2-Hydroxypenta-2,4-dienoate | ||||||||
| cis-Acetylacrylate, (L) | ||||||||
| 20 | 21.53 | 235.37(+1) | 0.57 | 23.64 | 263.37(+1) | 0.4 | 88.07 | Pyruvic acid, (S) |
| 21 | 21.65 | 236.36(+1) | 0.46 | 23.81 | 264.38(+1) | 0.33 | 89.08 | Oxamic acid, (S) |
| 21 | 21.75 | 235.37(+1) | 1.77 | 23.9 | 263.37(+1) | 1.25 | 88.07 | butyric acid, isobutyric acid, (S) |
| 21 | 21.75 | 237.34(+1) | 2.78 | 23.92 | 265.35(+1) | 1.97 | 90.05 | lactic acid, (S) |
| 22 | 21.98 | 295.30(+1) | 2.18 | 24.17 | 323.34(+1) | 1.54 | 148.04 | o-methylmalic acid, mono-, (R) |
| 22 | 22.1 | 264.33(+1) | 1.22 | 24.26 | 292.36(+1) | 0.86 | 117.06 | 3-Nitroacrylate, (L) |
| 23 | 22.23 | 269.34(+1) | 7.97 | 24.4 | 297.32(+1) | 5.65 | 122.02 | benzoic acid, (S) |
| 23 | 22.55 | 273.36(+1) | 1.14 | 24.47 | 301.36(+1) | 0.81 | 126.06 | 5-methylfuran-2-carboxylic acid, (R) |
| 23 | 22.58 | 287.36(+1) | 1.06 | 24.79 | 315.34(+1) | 0.75 | 140.04 | 2-hydroxy-2-ethylsuccinic acid, mono, (R) |
| 24 | 22.68 | 283.31(+1) | 2.37 | 24.82 | 311.39(+1) | 1.68 | 136.09 | phenylacetic acid, (S) |
| 25 | 22.98 | 263.39(+1) | 0.9 | 25.07 | 291.41(+1) | 0.63 | 116.01 | 3-Methyl-2-oxobutanoic acid |
| Hexylic acid | ||||||||
| 3-Oxopentanoic acid | ||||||||
| 2-Oxopentanoic acid, (L) | ||||||||
| 25 | 22.98 | 297.36(+1) | 1.01 | 25.08 | 325.41(+1) | 0.72 | 150.11 | 3-Phenyl-propionic acid, (S) |
| 26 | 23.48 | 322.35(+1) | 1.34 | 25.6 | 350.39(+1) | 0.95 | 175.09 | 3-indoleacetic acid, (S) |
| 26 | 23.57 | 299.35(+1) | 0.6 | 25.68 | 327.40(+1) | 0.43 | 152.1 | α-hydroxyphenylacetic acid, (S) |
| 27 | 23.67 | 313.35(+1) | 2.89 | 25.78 | 341.38(+1) | 2.04 | 166.08 | 4-hydroxyphenylhydracrylic acid, (R) |
| 28 | 23.88 | 323.36(+1) | 0.73 | 26.1 | 351.38(+1) | 0.52 | 176.08 | 5,6,7,8-Tetrahydro-2-naphthoic acid, (L) |
| 29 | 24.05 | 321.32(+1) | 0.44 | 26.2 | 349.34(+1) | 0.31 | 174.04 | suberic acid, mono-, (S) |
| 30 | 24.19 | 348.36(+1) | 0.53 | 26.31 | 376.38(+1) | 0.37 | 201.08 | U |
| 30 | 24.22 | 326.37(+1) | 0.84 | 26.38 | 354.37(+1) | 0.59 | 179.07 | hippuric acid, (S) |
| 31 | 24.37 | 340.37(+1) | 2.17 | 26.53 | 368.37(+1) | 1.54 | 193.07 | 5,6-Dihydroxyindole-2-carboxylate |
| Phenylacetylglycine | ||||||||
| D-Dopachrome, (L) | ||||||||
| 32 | 24.87 | 379.36(+1) | 1.23 | 27 | 407.38(+1) | 0.87 | 232.08 | Nalidixic acid, (S) |
a
Individual peak intensity was normalized to highest peak intensity of all peaks shown in the table.
b
Molecular weight was calculated from the m/z of a derivative and the mass of the tag. U - unidentified carboxylic acid; L - identification based on molecular mass matching from the LIGAND database; R - compound was also found in the literature; S - identification was confirmed by the standards.
c
This ion was also found in the standard chromatogram and was not represent it any carboxylic acid standards. It was treated as artifact.