2 show that only under a collision-induced voltage of -20 eV can fluid glutamate --prospective parent ion
146.1, be broken down for Sub ion and detected by an ion trap mass spectrometer.
A precursor ion scan of each individual di- and tripeptide was carried out to identify the m/z (mass-to-charge ratio) for each standard molecule to be used as parent ion
for the multiple-reaction monitoring (MRM) experiments (see below).
The Q1 scan was performed to select the parent ion
. The declustering potential (DP), entrance potential (EP) voltage values were further optimized to get highest intensity for parent ion
The parent ion
at m/z 182 was selected as the precursor ion for MS/MS analysis and m/z 82 as product ion.
It can be seen that both ionization methods result in a single parent ion
[[desomorphine + H].sup.+] at m/z 272 (Figures 1(a) and 1(c)), as well as characteristic fragments at m/z 215 and m/z 197, corresponding to proposed losses of [C.sub.3][H.sub.7]N and [C.sub.3][H.sub.7]N[H.sub.2]O (as seen in Figures 1(b) and 1(d)).
In addition, we obtained fragment ions at m/z 421 [[M-H-[C.sub.6][H.sub.10][O.sub.5]].sup.-] that displayed a loss of 162 Da [[C.sub.6][H.sub.10][O.sub.5]] based on the parent ion
. We also obtained fragment ions at m/z 331 [[M-H- [C.sub.6][H.sub.10][O.sub.5]-[C.sub.3][H.sub.6][O.sub.3]].sup.-] and 301 [[M-H-[C.sub.6][H.sub.10][O.sub.5]-[C.sub.4][H.sub.8][O.sub.4]].sup.-], which corroborated with the rules of C-glycoside loss of 90 ([C.sub.3][H.sub.6][O.sub.3]) and 120 Da ([C.sub.4][H.sub.8][O.sub.4]) from sugar molecules through [sup.0,3]X/[sup.0,2]X cleavage.
[t.sub.r] (min) [[M-H].sup.-] 260.7 2.2 180.0 2.1 145.9 4.5 Parent ion
Formula [[M-H].sup.-] 260.7 [C.sub.16][H.sub.10][N.sub.2][O.sub.2] 180.0 [C.sub.8][H.sub.7]N[O.sub.4] 145.9 [C.sub.8][H.sub.5]N[O.sub.2] Parent ion
Major mass fragmentation value (m/z) [[M-H].sup.-] 260.7 ES/: 247.1/242.8/221.6/214.7/200.7/176.8/146.7/118.7 180.0 ES-: 152.0/135.9/124.1/1073 145.9 ES-: 128.3/118.2 Parent ion
Compounds [[M-H].sup.-] 260.7 Indigo 180.0 4-(3-Hydroxy-1H-pyrrol-2-yl)-2-oxo-but-3-enoic acid 145.9 Isatin
With collision-induced dissociation of the parent ion
, all of the 3[beta]-hydroxy-[[DELTA].sup.5]-bile acid sulfates yielded a common intense base peak at m/z 96.6 resulting from loss of the sulfate group.
The ionizing voltage was -4200 V in the negative ion mode, the ion pair of the parent ion
(Q1)/daughter ion (Q3) was set up as the unit of discernment, and the dwell time of each ion pair was 150 ms.
It is found that the hybrid ion exchange resins have better removal capacity as compared to the parent ion
The parent ion
, daughter ion, cone voltage (V), and collision energy (eV) for bezafibrate detection were 360.22 > 274.12, 22, and 15.