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LA-ICP-MS

LASER ABLATION- INDUCTIVELY COUPLED

PLASMA- MASS SPECTOMETRY

Inductively Coupled Plasma Mass Spectrom-

Ms.Lorraine Tissan etry (ICP-MS) is an analytical technique used
to detect and measure elements present in

trace quantities from biological fluids, down to a detection limit of sub-parts
per million (ppm). This technique was discovered in 1980 and was first in-

troduced in the market in the year 1983. In the past decade, there has been
a gradually increasing shift in laboratories towards using ICP-MS instead

of older technologies like ICP AES (Inductively Coupled Plasma-Atomic
Emission Spectroscopy) and flame atomic absorption. The biggest advan-

tage ICP-MS has over the other technologies is its multi-element capabili-
ty, which allows the measurement of multiple elements in a single analysis.

Combined with its short analysis time and simple sample preparation, it is
highly unlikely that the steady shift of technologies would cease.

However, ICP-MS can only be performed on fluids after it undergoes sam-

ple preparation. Therefore, variants of this technology have emerged that
support the spectroscopic analysis of solid samples directly. Laser Ablation

ICP-MS is the most powerful of these variants.

Laser ablation is a process by which layers are removed from a solid sur-
face using a laser beam for ultimate precision. When a continuous wave

or pulsed laser light is focused onto a material, its electronic subsystem
and molecular lattice begin to absorb the energy, causing atoms to disso-

ciate from one another. These atoms subsequently ablate, either evaporat-
ing, sublimating, or converting directly into the plasma. These particles are

then transported to the plasma torch. The plasma in the ICP ionizes these
particles, generating ions, which are then extracted through the interface

region and into a set of electrostatic lenses called ion optics. The ion optics
focus and guide the ion beam into the quadrupole mass analyser. The mass

analyser separates ions according to their mass-charge ratio, and these ions
are measured at the detector. Laser Ablation ICP-MS can provide element

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