1. Gas Chromatography Compiled by : Imanuelle Orchidea 3325102413

2. Definition A chromatographic technique in which the mobile phase is a gas Gas Liquid Solid Gas –Liquid/ Gas-Solid Chromatography

3. perekam Tabung gas Rangkaian penghubung & penguat

4. Mobile phase Inert gas ( He, Ar, N 2 ) Carry the sample Flow rates determined with a flow meter placed at a column outlet Column typeFlow rate Packed column25-150 mL/min Capillary column1-25 mL/min

5. Packed columns Capillary columns

6. Packed Columns – Glass/stainless steel/copper/aluminum – 2-6 m in length, internal Ø 2-4mm – Particle Ø ranging from 37-44 µ m to 250-354 µ m – diatomaceous earth, glass beads, fluorocarbons polymers – Handle larger samples – Pressure needed to move mobile phase limits it’s length

7. Capillary Columns Open tubular column – Wall-coated – Support-coated Fused silica coated with protective polymer Up to 100 m in length Internal Ø 150-300 µ m, megabore up to 530 µ m Handle smaller samples ( < 10 -2 µL)

8. Photo of capillary column, taken from Harvey, David.T. Modern Analytical Chemistry

9. Stationary phase Choice of stat. phase  selectivity Criteria : – CHEMICALLY INERT – THERMALLY STABLE – LOW VOLATILITY – APPROPRIATE POLARITY R – SiR 2 – O - (SiR 2 – O) n – SiR 3 HO – CH2 – CH2 – (O – CH2 – CH2)n – OH

10. STAT.PHASEPOLARITYTRADE NAME(T)LIMITAPPLICATIONS SqualaneNon-polarSqualane150Low boiling aliphatic hydrocarbons Apezion LNon-polarApezion L300Amides Fatty acid methyl esters High boiling aliphatic HC Terpenoids Polydimethyl siloxane SlightlySE-30300-350Alkaloids* Amino acid derivatives ** Drugs # pesticides ## Phenols & steroids 50% methyl- 50%phenyl polysiloxane ModerateOV-17375*, #, ##, Polyaromatic hydrocarbons Polychlorinated biphenyls 50%TFP- 50%MPSO ModerateOV-210275*,**, #, halogenated compounds, ketones, phenols 50% CYP-50% phe-me-PSO PolarOV-225275Nitriles, pesticides, steroids PEGPolarCarbowax 20M 225Aldehydes, esters, ethers, phenols

11. Introduction of samples 1.All constituents must be volatile 2.Appropriate concentration 3.Must not degrade the separation Volatile analyte from Non volatile matrix: 1.Liquid-liquid extraction 2.Solid phase extraction  SPME 3.Headspace sampling 4.Cryogenic focusing

12. Injecting the sample Split injection Splitless injection On-column injection Schematic diagram of an injector for packed column GC

13. Detectors in GC Thermal Conductivity

14. Another detectors Flame photometric detector Thermionic detector FT-IR (GC-FT-IR) MS (GC-MS)

15. Quantitative applications Environmental analysis Clinical analysis/forensic may include Consumer goods Petroleum industry