Liquid Chromatography-Mass Spectrometry (LC-MS)

Liquid Chromatography-Mass Spectrometry (LC-MS) an usefull tool in pharmaceutical industries

1. Liquid Chromatography – Mass Spectrometry (LC-MS): an useful tool in pharmaceutical industries

2. Introduction Liquid chromatography–mass spectrometry ( LC-MS) is an analytical chemistry technique that combines the physical separation capabilities of   liquid chromatography (HPLC ) with the mass analysis capabilities of mass spectrometry  (MS ). LC-MS is a powerful technique that has very high sensitivity and selectivity and so is useful in many applications.   HPLC Mass spectrometry LC-MS

3. Components

4. Non polar stationary phases like C 8 column , C 18 column phenyl-bonded silica (intersil Ph-3). Water, Acetonitrile, methanol etc. Length : 150mm(large column) ; 50mm(short column) Internal diameter : 2mm - 4.6mm 0.05 to 0.2 mL/min HPLC

5. Mass spectrometry

6. Ionization and Interface Atmospheric Pressure Chemical Ionization (APCI) Atmospheric Pressure Photo Ionization(APPI)

7. Electron trap Electrically heated metal coil Ion repeller Ionisation Vaporized sample .……………… ………………. ………………. + + + + Acceleration

8. Atmospheric Pressure Chemical Ionization (APCI)

9. Thermo Spray Ionization (TSI) Atmospheric P ressure Photo Ionization (APPI)

10. Mass analysers Fourier Transform-Ion Cyclotron Resonance analyser (FT-ICR) A mass analyser is the component of the mass spectrometer that takes ionized masses and separates them based on charge to mass ratios and outputs them to the detector where they are detected and later converted to a digital output.

11. + + + + + + + + + + + + + D eflection

12. Time of Flight Analysers Ion trap analyser

13. Fourier Transform-Ion Cyclotron Resonance Analyser

14. Detectors The detector records either the charge induced or the current produced when an ion passes by or hits a surface. In a scanning instrument, the signal produced in the detector during the course of the scan versus where the instrument is in the scan (at what m/z ) will produce a mass spectrum, a record of ions as a function of m/z . Typically, some type of electron multiplier is used, though other detectors including Faraday cups and ion-to-photon detectors are also used. Microchannel plate detectors are commonly used in modern commercial instruments. Because the number of ions leaving the mass analyser at a particular instant is typically quite small, considerable amplification is often necessary to get a signal. A continuous dynode particle multiplier detector

15. Faraday cup Detector

16. Detection

17. Mass spectrum of elements Zirconium Chlorine

18. 4-methyl-3-pentene-2-one N,N - diethylmethylamine Mass spectrum of chemical compounds

19. Molecular weight determination Toxicology Impurity detection Applications Determination of isotopes

20. http ://en.wikipedia.org/wiki/Mass_spectrometry https :// www2.chemistry.msu.edu/faculty/reusch/virttxtjml/Spectrpy/ Mass Spec/masspec1.htm http ://www.chemguide.co.uk/analysis/masspec/howitworks.html http :// www.bris.ac.uk/nerclsmsf/techniques/hplcms.html http :// chemwiki.ucdavis.edu/Analytical_Chemistry/Instrumental_Analysis / Mass_Spectrometry/Mass_Spectrometers_%28Instrumentation%29/Mass_Analyzers_% 28Mass_Spectrometry%29 https:// www.jic.ac.uk/services/metabolomics/topics/lcms/why.htm Reference