What are the Differences between GC and HPLC?

Gas chromatography (GC) vs High-Performance Liquid Chromatography (HPLC)

GC stands for Gas chromatography (Refer: Gas Chromatography (GC)) and HPLC stands for High-Performance Liquid Chromatography.
Both are separation techniques that have added massive popularity in industrial laboratories.

HPLC (High-Performance Liquid Chromatography) has applications in pharmaceuticals, foods, life sciences and polymers
Gas Chromatography (GC) has imperative applications in the environmental air monitoring, petroleum and petrochemical industry, & flavours and fragrances.

High-Performances Liquid Chromatography as name suggested liquid used as mobile phase whereas GC (Gas chromatography) operated by gas as the carrier.
Liquids are mostly mixtures of solvents and buffers of compatible polarities. In gas chromatography, the mobile phase is a high purity gas carrier.

Operating temperature of HPLC is mostly carried out at ambient temperatures (around 25°C) while Gas Chromatography separations are operated at elevated temperatures (around 250°C) which can be maintained at a constant value (isothermal) or variable as decided by the temperature program on the requirement of analytical methods.
Newer packings & external column oven have extended temperature limits of HPLC at some point for operation as well.
Temperature programmed gas chromatography (TPGC) is the procedure of cumulative the column temperature during a run in GC.

Gas chromatography separations are mainly carried out on compounds that are volatilities and remain stable at high temperatures that may be up to a few hundred in molecular weights.
HPLC can be used in compounds having higher molecular weights ranging from a few hundred to several million for large polymers and biomolecules. They are mainly operated at room temperature as on elevated temperatures compounds have a tendency to degrade.

HPLC (High Performance Liquid Chromatography) normally uses columns that are shorter with wider diameters in comparison to GC columns.
Because in HPLC Mobile phase having the liquid which have higher viscosity, which leads to creating more back pressure.
In GC columns are much longer and narrower. Enlarged column length advances resolution between closely spaced peaks..
C8 & C18 Column packings used in HPLC.
GC Chromatography uses packed and capillary columns which have a higher permeability of solid supports than liquids.
The retention of analyte HPLC columns mainly depends on polarity differences or molecular sizes.
GC Chromatography separations are built on differences in volatilities of sample.

Type of HPLC Detectors: are UV-Vis, RI, photodiode array detectors (PDA), conductivity and laser detection.
GC Detectors are FID, NPD and FPD.
Mass spectrometry detectors common to both like LCMS and GCMS.

HPLC solvents are more costly in contrast to gases used for GC Chromatography analysis.
Maintenance charge of GC and HPLC depends on use, but due to high use and requirement of solvent to operate HPLC costly than GC.
Tandem techniques like LC-MS-MS and GC-MS-MS have prolonged the limits of detection to new frontiers of detection and automation in machines has also donated to increased laboratory uses.

More Topic: