This video explains the principle of Inductively coupled plasmaAtomic emission spectrometry or Inductively coupled plasmaAtomic emission spectroscopy. It also explains the instrumentation and working of Inductively coupled plasmaAtomic emission spectrometry (ICPAES). It also explains the applications of ICPAES.
You will be able to
elucidate the principle of inductively coupled plasmaatomic emission spectroscopy (ICPAES).
explain the instrumentation and working of ICPAES.
list out the applications of ICPAES.
Principle of Inductively coupled plasmaAtomic emission spectrometry ICPAES :
Excitation of atomised metal with inductively coupled plasma, followed by emission of light of its own characteristic wavelength and the correlation of the emitted light with the concentration of the metal is Inductively coupled plasmaAtomic emission spectrometry (ICPAES).
Used to detect trace metals in ppm
Nebuliser converts liquid solution to fine particles of aerosol/mist
Solvent gets vapourised leaving behind the solid residue.
The solid residue gets vapourised to gaseous form due to high temperature of the plasma and the molecules dissociate to atoms.
The metal atoms get excited to higher energy level .
The excited metal atoms emit light of its own characteristic wavelength by returning back to the ground state. (Ni 393nm, Cu 325nm Na 589nm, Li 670nm, Ca 622 nm, Ba554nm).
Instrumentation & Working of Inductively coupled plasmaAtomic emission spectrometry ICPAES.
Source – Plasma is an electrically neutral conducting gaseous mixture (cations and electrons). It is heated inductively by coupling with an oscillating magnetic field (radio frequency). The temperature of the plasma may be of the order of 5,000 to 10,000 K – eg. plasma torch.
RF generator Radio frequency generator creates the RF signal and intense electromagnetic field is created in the induction coil when the torch is switched on. A plasma at temperatures up to 10,000 K is created due to an ignition of a spark from a Tesla coil (the seed electrons from the Tesla coil oscillate in an angular path and periodically collide with argon gas atoms and ionize them, releasing more electrons. Due to their kinetic energy and collisions with other atoms a large amount of heat is generated, enough to generate and sustain a plasma).
Nebuliser and spray chamber – Converts the liquid sample to mist and sprays the fine particles along with argon gas into the plasma.
Atomiser – Converts the analyte molecules to gaseous atoms, which gets excited and returns back to the ground state by emitting light of its characteristic wavelength.
Monochromator – Polychromatic light is dispersed into individual wavelengths e.g. diffraction grating , Rowland circle, etc.
Detector – The intensity of light with different wavelengths is measured using (i) a set of photomultiplier tubes (generates current proportional to the intensity of the light) or (ii) fall on the array of semiconductor detectors such as charge coupled devices (CCD’s), photodiode arrays etc.
Data processor and display Data from these detectors are processed and multiple wavelengths are measured at the same time (higher the concentration higher is the intensity of emitted light ).
Applications of Inductively coupled plasmaAtomic emission spectrometry ICPAES
Agriculture: : Analysis of agricultural products, food and soil samples
Biomedical : Determination of Al in blood, Cu in brain, Se in liver, Na in breast milk.
Geology : Presence of lanthanides and other elements in rock samples.
Forensic : Crime scene food samples, blood samples, soil analysis etc.
Metallurgy : Analysis of trace elements in metals and alloys.
Environmental science : Waste water analysis, metals in soil water etc.
Petroleum industries : Presence of metals like Cu, Fe, Ni, and Si in lubricating oils or gasoline at tracer concentration.
Beverages : Traces of metals like Ca, Cu, Fe, Mn, Mg, P, K and Zn in beverages.
Miscellaneous : Determination of trace elements in polymers, catalysts etc.
Agriculture: : Analysis of agricultural products, food and soil samples
Biomedical : Determination of Al in blood, Cu in brain, Se in liver, Na in breast milk.
Geology : Presence of lanthanides and other elements in rock samples.
Forensic : Crime scene food samples, blood samples, soil analysis etc.
Metallurgy : Analysis of trace elements in metals and alloys.
Environmental science : Waste water analysis, metals in soil water etc.
Petroleum industries : Presence of metals like Cu, Fe, Ni, and Si in lubricating oils or gasoline at tracer concentration.
Beverages : Traces of metals like Ca, Cu, Fe, Mn, Mg, P, K and Zn in beverages.
Miscellaneous : Determination of trace elements in polymers, catalysts etc.