19C: Investigate chromatographic techniques to identify components and determine the amounts
present in samples.
Chromatography
Introduction:
Introduce what the assignment is about. Use the vocational context.
You are a junior technician working for an international pharmaceutical company. Based in the
company’s UK research site, you use Gas Chromatography (GC) and High-Performance Liquid
Chromatography (HPLC) techniques to routinely identify compounds made by the research chemists
in order that they are able to monitor their progress towards their research goals. Each year your
department gives a two week work experience placement for a sixth form student. To prepare for
this, you will create an instructional handbook to give to the students an overview of the work they
will be carrying out whilst on placement
What is chromatography? Why is it important.
Chromatography is a method used to separate and quantify the component of mixture. it is based on
the principle that mobile phase will interact differently to different component of the compound
when being passed though the stationary phase, causing the separation of the component based on
either their chemical or physical properties. The stationary phase can ither be solid or liquid while
the mobile phase can either be solid or gas.
Chromatograph is important it allow scientist to analyse complex samples, detect trace amount in a
compound and find out the chemical composition of a substance. It can be used in scientific research
for quality control or the development of new compound. there are used in variety of industries such
as pharmaceutical, food and beverage forensic, etc
Task 1: The function of Capillary GC and HPLC.
What is capillary GC?
capillary GC, also referred to as Gas chromatography (GC), is a technique used to separate the
component of a mixture which won’t break down when vaporises . the capillary GC is a very narrow
tube with the stationary phase coating the interior surface. The narrow sillica tube in the capillary GC
allows for high resolution separation because it provides a large surface area for the sample and
stationary phase to interreact with. This can result in a better resolution of the peaks and higher
efficiency when separating. Capillary GC can use small sample volumes and can allows for faster
analysis .
, Discuss briefly of how it works.
The process beings with the sample, usually a liquid or gas, is introduced to the GC system. Once
inside, it will undergo vaporisation and is carried by the carrier gas which is an inert gas. the inert gas
will facilitate movement of the sample into the capillary column where separation will take place.
In the capillary column, the sample interact with the stationary phase which is a thin coating in the
inner lining of the capillary. The interaction is affected by many factors such as volatility, size, polarity
and the type of stationary phase used. As the component travel though the capillary, the component
will start to separate based on there affinity. Component with higher affinity will take longer to
separate than those with weaker affinity. After separation, the component will leave the capillary at
different times. When the component leaves the capillary is directed to a detector for analysis. The
detector used are usually flame ionization detector ( FID) or mass spectrometer. The detector will
generate a signal to produce a chromatogram
What is HPLC?
HPLC which is a abbreviated term for High-performance liquid chromatography is an analytical
technique used to separate and quantify each component of a mixture. This technique uses a
pressurised mobile phase that will be passed though columns that is packed with the stationary
phase
HPLC offers several advantages over other chromatographic techniques. It provides high-resolution
separations, allowing for the analysis of complex samples and the detection of trace-level analytes.
HPLC is versatile, as different types of columns and stationary phases can be used for specific
separation needs. It can also handle a wide range of sample types, including polar and non-polar
compounds.
Discuss briefly of how it works.
The sample mixture will be dissolved in suitable solvent and then introduced into the HPLC system
using an autosampler. The mobile phase is then pumped at a constant rate through the columns. The
columns are packed with the stationary phase which are usually small particles or bead that are
made up of silica, polymer, or other modified substance. These beads are coated with a specific
substance based on the separation requirements. The interaction of the sample with the stationary
phase is dependent of variety of factors such as polarity, charge, size, chemical properties, etc. . As
the component travel though the component, the component will start to separate based on their
affinity. Component with higher affinity will take longer to separate than those with weaker affinity.
After separation, the component will leave the capillary at different times. When the component
leaves, the column is directed to a detector for analysis. The detectors used are usually as UV
absorbance, refractive index, fluorescence, or mass spectrometry. The detector will generate a signal
to produce a chromatogram.