What are the limitations of chromatography?

Answer 1

Some drawbacks of gas chromatography include:

1. The samples analysed are limited to those that are volatile or can be made volatile (reaction to form a volatile derivative).
2. The samples must be thermally stable to prevent degradation when heated.
3. Cannot be used to prepare samples for further analysis once separated.
4. Problems can be encountered when injecting the sample:

• It is difficult to measure and inject such small samples (approx 0.3microlitres) accurately without evapouration of the sample, for example.
• The rubber seal through which the sample is injected may leak leading to loss of the sample.
• Small pieces of the rubber septum may be adsorbed onto the column giving 'ghost peaks'.
• The sample may be injected directly into the heated part of the injector so vapourisation may not occur (and the sample is lost).

Answer 2

Difficult to reproduce, spots are often faint and not typically automated

spots are often faint, and TLC is difficult to reproduce. NOT typically automated

more points on liquid chromatography:

• Over-large Spots
• Uneven Advance of Solvent Front
• Streaking
• Spotting

Answer 3

Gas chromatography can only be used in cases where the substances can be vaporized without decomposing and where they can be vaporized at a reasonable temperature (i.e. not so hot that it destroys the column packing).

Answer 4

Advantages of HPLC • Speed (minutes) • High resolution • Sensitivity (ng to fg) • Reproducibility of +/- 1% • Accuracy• Automation Disadvantages of HPLC • Cost • Complexity • Low sensitivity for some compounds • Irreversibly adsorbed compounds not detected • Co-elution difficult to detect Isaac Kiplagat, MSc
High performance liquid chromatography (HPLC) is used to separate and identify compounds based on their polarity. The advantages of HPLC is that produces results within a few minutes. The results are high resolution and easily reproduced and tested.

Answer 5

That mainly depends on what kind of L.C. (Liquid Chromatography) is meant:

• GLC = gas L.C. (Liquid as stationairy phase)
• LLC = counter current liquids chromatography
• SLC = Solid L.C. (Solid as stationairy phase, e.g. TLC = 'Thin layer' L.C. or Paper L.C. )

Answer 6

It's expensive to buy a GC/MS machine. The tubes you use for each sample are expensive. You need a trained operator. If you don't have your own machine you'll have to send the specimen off to be tested. And it's slower than most other ways of analyzing samples.

The other thing about GC/MS is either an advantage or a disadvantage depending on who you are. GC/MS is very, very accurate. If you smoke weed, being tested on an extremely accurate machine is a disadvantage. If you're trying to catch pot smokers, it's definitely an advantage.

Answer 7

the draw backs is that are that they will loos money

Answer 8

Chromatography can not be used in quantitative analyses and it doesn't allow the separation of complex mixtures. These are the limitations of chromatography.

Answer 9

An advantage of column chromatography is that is has both preparative as well as analytical applications. A disadvantage is the technical skill required to properly set up the column.