Study Set Content:
the most generally applicable and most widely
used detectors. the sample is directed at
an air hydrogen flame after exiting the column.
2. Flame Ionization Detectors (FID)
are highly selective detectors commonly used for
detecting environmental samples as the device
selectively detects organic compounds with
moieties such as halogens, peroxides, quinones
4. Electron-Capture Detectors (ECD)
one the earliest detectors developed for use with
gas chromatography. The TCD works by
measuring the change in carrier gas thermal
conductivity caused by the presence of the
sample, which has a different thermal
conductivity from that of the carrier gas.
3. Thermal Conductivity Detectors (TCD)
one of the newest addition to the gas
chromatographer's arsenal, are element-selective
detectors that utilize plasma, which is a partially
ionized gas, to atomize all of the elements of a
sample and excite their characteristic atomic
emission spectra.
Atomic Emission Detectors (AED)
a process in which both qualitative and
quantitative properties can be determined using
the optical emission from excited chemical
species.
6. Chemiluminescence spectroscopy (CS)
this method is best suited in applications
where traces quantities of chemicals such as
pesticides are to be detected and other
4. Electron-Capture Detectors (ECD)
An extremely powerful alternative that has a
wider applicability due to its based on the
detection of atomic emissions.
5. Atomic Emission Detectors (AED)
which utilizes the properties of
chemiluminescence spectroscopy. Photoionization
detector (PID) is a portable vapor
and gas detector that has selective determination
of aromatic hydrocarbons, organo-heteroatom,
inorganic species and other organic compounds.
7. Photoionization detector
It is very similar to AES, but the difference is that
it utilizes the light emitted from the energized
molecules rather than just excited molecules.
6. Chemiluminescence spectroscopy (CS)
APPLICATIONS:
1. Environmental Analysis
2. Clinical Analysis
3. Forensic Analysis
4. Consumer Products
5. Petrochemical and Chemical Industry
A technique in analytical chemistry used to separate, identify and quantify each component in
a mixture.
HPLC (High Performance Liquid Chromatography)
Is the most versatile and widely used type of elution chromatography.
HPLC (High Performance Liquid Chromatography)
HPLC resembles the other chromatography has a
mobile phase, and stationary phase.
A liquid mobile phase is pumped under pressure through a stainless-steel column containing
particles of stationary phase with a diameter of
3-10 um.
The analyte is loaded onto the () of the column via a () and separation of a
mixture occurs according to the relative() spent by it's components in the
stationary phase.
head, loop valve, lengths of time
Monitoring of the column effluent can be carried out with a variety
detectors
Utilize polar adsorbent surface and non-polar eluent.
Normal Phase HPLC
– most commonly used form of HPLC.
Reversed Phase HPLC
Solvents used in mobile phase:
hexane, heptane, cyclohexane, carbon tetrachloride, benzene,
toluene, diethyl ether, chloroform
Adsorbents used in stationary phase:
Silica gel, alumina, celite, cellulose powder, ion-
exchange, cellulose, starch.
