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2. Liquid chromatography–mass spectrometry - Wikipedia

   en.wikipedia.org/wiki/Liquid_chromatography...

   Liquid chromatography–mass spectrometry (LC–MS) is an analytical chemistry technique that combines the physical separation capabilities of liquid chromatography (or HPLC) with the mass analysis capabilities of mass spectrometry (MS). Coupled chromatography – MS systems are popular in chemical analysis because the individual capabilities ...

3. High-performance liquid chromatography - Wikipedia

   en.wikipedia.org/wiki/High-performance_liquid...

   A modern self-contained HPLC Schematic representation of an HPLC unit (1) solvent reservoirs, (2) solvent degasser, (3) gradient valve, (4) mixing vessel for delivery of the mobile phase, (5) high-pressure pump, (6) switching valve in "inject position", (6') switching valve in "load position", (7) sample injection loop, (8) pre-column (guard column), (9) analytical column, (10) detector (i.e ...

4. Reversed-phase chromatography - Wikipedia

   en.wikipedia.org/wiki/Reversed-phase_chromatography

   A mobile phase in reversed-phase chromatograpy consists of mixtures of water or aqueous buffers, to which organic solvents are added, to elute analytes from a reversed-phase column in a selective manner. [7] [27] The added organic solvents must be miscible with water, and the two most common organic solvents used are acetonitrile and methanol.

5. Chromatography - Wikipedia

   en.wikipedia.org/wiki/Chromatography

   The mobile phase consists of the sample being separated/analyzed and the solvent that moves the sample through the column. In the case of HPLC the mobile phase consists of a non-polar solvent(s) such as hexane in normal phase or a polar solvent such as methanol in reverse phase chromatography and the sample being separated. The mobile phase ...

6. Monolithic HPLC column - Wikipedia

   en.wikipedia.org/wiki/Monolithic_HPLC_column

   The basic methods of separation in HPLC rely on a mobile phase (water, organic solvents, etc.) being passed through a stationary phase (particulate silica packings, monoliths, etc.) in a closed environment (column); the differences in reactivity among the solvent of interest and the mobile and stationary phases distinguish compounds from one ...

7. Atmospheric-pressure chemical ionization - Wikipedia

   en.wikipedia.org/wiki/Atmospheric-pressure...

   Atmospheric pressure chemical ionization chamber cross section. Atmospheric pressure chemical ionization (APCI) is an ionization method used in mass spectrometry which utilizes gas-phase ion-molecule reactions at atmospheric pressure (10 5 Pa), [1] [2] commonly coupled with high-performance liquid chromatography (HPLC). [3]

8. Two-dimensional chromatography - Wikipedia

   en.wikipedia.org/wiki/Two-dimensional_chromatography

   The sample is first subjected to analysis by HPLC and then is subjected to mass analysis. Different types of mass analyzers, ToF, qudrupole, etc., can be used in the MS. [5] Common solvents used in normal or reversed phase LC such as water, acetonitrile, and methanol are all compatible with ESI, yet a LC grade solvent may not be suitable for MS.

9. Direct electron ionization liquid chromatography–mass ...

   en.wikipedia.org/wiki/Direct_electron_ionization...

   However, the possibility to record an EI spectrum from an HPLC application remained a challenge for a long time. The first Direct-EI prototype was first presented in 2002 [5] and proposed an innovative approach that improved interfacing performance compared to that of particle beam and opened new opportunities for LC-MS applications.