The applicability of the chip suppressor has been demonstrated with an isocratic baseline separation of a mixture of seven inorganic ions, yielding plate numbers between 5300 and 10,600 and with a gradient separation of a complex ion mixture.
The RPC total ion current (TIC) chromatogram obtained for HIC fraction 2 clearly shows baseline separation of a number of proteins, demonstrating the power of the two-dimensional separation.
Fig. 9c shows the nearly baseline separation of a standard mixture of levulinic acid, 2,5-hexanedione, 5-HMF, 2,5-dimethyltetrahydrofuran, furfural, methylfuran, 5-methylfurfural and 2,5-dimethylfuran, eluting within only 4 min.
A baseline separation of all the 12 aliphatic aldehydes (except formaldehyde and acetaldehyde) is achieved in 20 min with acetonitrile tetrahydrofuran (THF water as mobile phase.
A baseline separation of all the six derivatives is achieved by isocratic elution on reversed-phase column within 20 min with detection wavelengths of 500 and 510 nm for the excitation and emission, respectively, and the limits of detection (signal-to-noise ratio = 3) are from 1.8 fmol (CoA) to 14.0 fmol (HCys), respectively, per 20 μL injection.
The superior specificity of MS allows the simplification of sample preparation, and the application of fast gradient methods, where a baseline separation of all components is not required.
Baseline separation of all the components was achieved in time less than 1 min.
The inspection of the response surface indicated an optimum electrolyte composition as 10 mmol L−1 STB (pH 9.3) containing 40 mmol L−1 SDS and 1% MeOH promoting baseline separation of all isoflavones in less than 7.5 min.
The baseline separation of all arsines that are quickly released from the CT, typically within 50 s, is also crucial.
Through using such a 140 min gradient, regeneration, and re-equilibration program, it was possible to achieve sufficiently stable retention times over 72 h of constant operation, such that baseline separation of all isobaric UDP-sugar pairs was given in all measurements and also their elution order remained unchanged, which facilitated the unequivocal identification of the separated UDP-sugars.
