Samsung RT34M Manual do Utilizador descarregar pdf (Página 37)

Dushyant Patel LC-MS/MS Method

S.K.P.C.P.E.R., Kherva 25 M .Pharm. Thesis

Figure 4.3 APCI process in the positive ion polarity mode

Scan modes:

¾ The mass spectrometer can be operated in a variety of scan modes. The most commonly

used scan modes can be divided into two categories: single mass spectrometer scan

modes and MS/MS scan modes. The scan modes in each category are as follows:

• Mass spectrometer scan modes: Q1MS and Q3MS

• MS/MS scan modes: Product, Parent, Neutral Loss

• Data dependent scan mode

¾ The scan modes that can be employed depend on the number and type of rod assemblies

and the voltages applied to the rod assemblies. The mass analyzer has three rod

assemblies. The first and third rod assemblies, Q1 and Q3, are Hyper Quads (hyperbolic-

profile quadrupoles), and the second rod assembly, Q2, is a square-profile quadrupole.

¾ Rod assemblies can be operated in either of two capacities:

• Ion transmission devices

• Mass analyzers

¾ If only RF voltage is applied, a rod assembly serves as an ion transmission device that

passes all ions within a large range of mass-to-charge ratios (i.e., virtually all ions

present).

¾ When both RF and DC voltages are applied to a rod assembly, the separation of ions of

different mass-to-charge ratios occurs. This separation allows the rod assembly to serve

as a mass analyzer.

1 2 ... 32 33 34 35 36 37 38 39 40 41 42 ... 92 93

Sem comentários

Samsung RT34M Manual do Utilizador Página 37