Epa-method-6020a Inductively Coupled Plasma-mass Spectrometry
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Laser Ablation Inductively Coupled Plasma Mass Spectroscopy-A Review
*Dr. Bhavyasri. Khagga1, Dhana Lakshmi.Chinta2, Swetha sri. R3
1Department of pharmaceutical analysis, Associate Professor, RBVRR women’s college of
pharmacy, Barkatpura, Hyderabad, Telangana, India.
2Department of pharmaceutical analysis, Research Student, RBVRR women’s college of
pharmacy, Barkatpura, Hyderabad, Telangana, India.
3Department of pharmaceutical analysis, Assistant Professor, RBVRR women’s college of
Pharmacy, Barkatpura, Hyderabad, Telangana, India.
Corresponding Author Email:[email protected],
Abstract:
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has received
significant attention over the last 10 years and has been widely used for analysis of biological
samples. The technique allows elements and isotopes determination in biological tissues and related
materials with a spatial resolution typically ranging from 10-100 µm. When compared to other
techniques usually employed to obtain bio images, the greater advantage of LA-ICP-MS is its
higher sensitivity. Applications of isotope ratio (IR), including trace experiments, and isotope
dilution (ID) are reviewed for biological samples (briefly for proteins, only in order to show the
utility of LA-ICP-MS). Bio imaging methods, studies and applications to animal and plants tissues
are emphasized, demonstrating the importance bio images of metals and metalloids in biomedical
research, bioaccumulation and bioavailability studies for ecological and toxicological risk
assessment in humans, animals and plants.
Key words: LA-ICP-MS, Plasma, Photons, Energy, Elements, Isotopes, Atomizing, Ionizing.
1. Introduction:
LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometry) is a powerful
analytical technology that enables highly sensitive elemental and isotopic analysis to be performed
directly on solid samples. LA-ICP-MS begins with a laser beam focused on the sample surface to
generate fine particles – a process known as Laser Ablation. The ablated particles are then
transported to the secondary excitation source of the ICP-MS instrument for digestion and
ionization of the sampled mass. The excited ions in the plasma torch are subsequently introduced to
a mass spectrometer detector for both elemental and isotopic analysis [1].
1.1. Benefits of LA-ICP-MS:
LA-ICP-MS is one of the most exciting analytical technologies available because it can
perform ultra-highly sensitive chemical analysis down to ppb (parts per billion) level —
without any sample preparation.
Samples can be both conducting or non-conducting, and the analysis can be performed
in the air without the need for a complex vacuum system. Results are available within
seconds; therefore, LA-ICP-MS delivers that fastest analysis speed of all analytical
techniques with the limit of detection approaching ppb level.
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The sample mass size required for LA-ICP-MS analysis is sub-microscale —
picograms to femtograms. Traditional liquid nebulization approaches for ICP-MS
require the removal of milligrams of sample mass in order to be effective [2].
When applied with optimized laser ablation conditions and ICP-MS data acquisition
protocols, LA-ICP-MS allows versatile solid sampling schemes that include:
Bulk analysis
Local inclusion and defect analysis
Depth profiling
Elemental/isotope mapping
The two most commonly used laser-based methods are bulk analysis with a typical laser
spot size of 100 ~ 350μm and microanalysis with the laser spot size as small as a few
microns.
2. Principle:
Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. As a
consequence of its light-amplifying property, a laser produces spatially narrow and extremely
intense beams of radiation having identical frequency, phase, direction and polarisation properties.
According to the resonance condition (∆E = hv) and to the rules of quantum mechanics, an atom
can change its energy level, which leads to the absorption or emission of a photon. Stimulated
emission is the basis of laser behaviour. Stimulated emission leads to the emission of a coherent
radiation with the incoming radiation. In order to have light amplification in a laser it is necessary
that the number of photon produced by stimulated emission exceed the number of photons lost by
absorption. This light amplification is only achieved when a population inversion from the normal
distribution of energy state exists. This population inversion (activation of a laser material) is
created by an external pumping source, so that a few photons of proper energy will trigger the
formation of a cascade of photons of the same energy. This cascade of photons is focussed on a
sample. Interaction between the laser beam allows the conversion of photon energy into thermal
energy, which is responsible for the vaporisation of most of the exposed solid surface. The material
ablated is swept away with an argon stream to an Inductively Coupled Plasma Mass Spectrometer
(ICP-MS) and analysed [3].
3. Instrumentation:
Figure 1. Block diagram of LA-ICP-MS.
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The LA-ICP-MS instrument consists of
Laser ablation chamber
Inductively coupled plasma(ICP)
Mass spectroscopy(MS)
These parts are discussed in detail in the following:
Figure 2. Instrumentation of LA-ICP-MS.
3.1. Concept of LA-ICP-MS:
Laser Energy
↓
Solid sample
↓
Solid vaporization
↓
Dissociation
↓
Atomization
↓ in ICP-MS
Ionization/Excitation of elements
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3.2. What Is Laser Ablation?
Laser ablation or photoablation is the process of removing material from a solid (or occasionally
liquid) surface by irradiating it with a laser beam. At low laser flux, the material is heated by the
absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically
converted to a plasma. Usually, laser ablation refers to removing material with a pulsed laser, but it
is possible to ablate material with a continuous wave laser beam if the laser intensity is high
enough. Excimer lasers of deep ultra-violet light are mainly used in photoablation; the wavelength
of laser used in photoablation is approximately 200 nm. Lasers are such as the frequency-
quadrupled Nd: YAG (Neodymium-doped yttrium aluminium garnet) in which the atoms that emit
light are fixed within a crystal or a glassy material. Lasers are characterised mainly by their
wavelength (1064 nm for a Nd: YAG), output power and pulse length fixed by the design of the
laser (nanosecond or picosecond) [4-5].
Figure 3. Laser ablation chamber.
3.3. What Is ICP-MS?
It is an inorganic (elemental) analysis technique.
ICP-Inductively Coupled Plasma.
High temperature ion source.
Decomposes, atomizes and ionizes the sample.
MS - Mass Spectrometer.
Featuring quadrupole mass analyser.
Mass range - 7 to 260 amu (Li to U...).
Separates all elements in rapid sequential scan.
Ions measured using dual mode detector.
Ppt to ppm levels.
Isotopic information available.
3.3.1. Inductively coupled plasma:
An inductively coupled plasma is a plasma that is energized (ionized) by inductively heating the gas
with an electromagnetic coil and contains a sufficient concentration of ions and electrons to make
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the gas electrically conductive. The plasmas used in spectrochemical analysis are essentially
electrically neutral, with each positive charge on an ion balanced by a free electron. The plasma
used in an ICP-MS is made by partially ionizing argon gas (Ar → Ar+ + e−). The energy required
for this reaction is obtained by pulsing an alternating electric current in wires that surround the
argon gas. The Sample first atomizes then ionize and detected. Icp for spectrometry is sustained in a
torch [6-8].
3.3.2. Basic functional components-ICPMS:
3.3.3. Instrumentation:
Sample introduction system.
Icp torch.
Interface.
Vacuum system.
Collision/ reaction cell.
Ion optics.
Mass spectrometer.
Detector.
Figure 4. ICP-MS instrument.
a) Sample introduction system:
Composed of a nebulizer and spray chamber. Liquid sample introduced to nebulizer by
peristaltic pump. Aerosol formation. Fine droplets are passed through spray chamber.
Argon gas is used.
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b) ICP torch:
Argon plasma @10000K. Copper coil connected to RF generator. Collisions of electron
with argon atoms. Ionization of Ar. Oscillation of ions and electrons. Ion transfer from
atmospheric pressure to vacuum.
c) Interface:
Allow the plasma and ion lens to coexist. Allows ions generated by plasma to pass through
ion lens. It consists of 2-3 cones. Downstream focusing of ion is done by charged ion
lenses. If 3 cones are used, then there is no need for ion lens.
Interface serves to direct the ions toward the mass spectroscopy.
Interface area consists of two conical metal (usually nickel) called sampler cone and
skimmer cone, each with small holes to allow ions to pass through to the ion optics.
Figure 5. Interface.
d) Collision\reaction cell:
Interferences caused when ions carry a mass-to-charge ratio identical to analyte ion. Passing
both through a cloud of inert gas molecules. Kinetic energy discrimination. Collision cell
can be a reaction cell. Inert gas is used. No-gas mode - no gas in the cell - the instrument
performs like a standard ICP-MS. High sensitivity is achieved for all elements. This mode
is typically used for uninterfered elements such as Be, Hg, Pb Helium (Collision) mode -
used for all analytes that suffer matrix-based Interferences are removed based on their
physical size (Reaction) mode - used only for the very few situations where He collision
mode is not efficient enough.
Figure 6. Reaction mode.
e) Ion optics:
Delivers ions toward the quadrupole. Stop or hinder the electrons, protons and neutrons to
the detector analyser[9-14].
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Fig-7: Ion Optics.
3.4. Mass Spectroscopy:
Principle: In this technique the compounds under investigation are bombarded with a beam of
electrons which produce an ionic molecule. The resulting assortment of charged particles is then
separated according to their masses.
1/2mv²=eV. (1)
m=Mass of particle.
v=velocity of particles.
e=charge on electron.
V=accelerating voltage.
3.4.1. Mass Analysers:
After ions are formed in the source region they are accelerated into mass analysers by electric field.
They deflect ions down a curved tube in a magnetic fields based on their kinetic energy determined
by the mass, charge and velocity [15-17].
The magnetic field is scanned to measure different ions.
Types of mass analyser:
(1) Quadrapole mass filter.
(2) Magnetic sectors.
(3) Time of flight.
(4) Ion trap.
1) Quadrapole mass analyser:
In 1955 introduced by W. Paul. A Quadrupole mass filter consists of four parallel metal
rods with different charges. Two opposite rods have an applied + potential and the other two
rods have a – potential. The applied voltages affect the trajectory of ions traveling down the
flight path. For given DC and AC voltages, only ions of a certain mass-to-charge ratio pass
through the quadrupole filter and all other ions are thrown out of their original path.
Potential of 5-10 V applied. High scan rates [18].
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Fig-8: Quadrapole mass analyser.
2) Magnetic sectors:
Designed by mattauch and herzog. Electrostatic field applied. Selection of ions of certain
velocity or K.E. High resolution. Used for determination of precise molecular weight.
Figure 9. Magnetic sector.
3) Time of flight(TOF):
TOF Analysers separate ions by time without the use of an electric or magnetic field. In a
crude sense, TOF is similar to chromatography, except there is no stationary/ mobile phase,
instead the separation is based on the kinetic energy and velocity of the ions.
4) Ion trap:
TOF Analysers separate ions by time without the use of an electric or magnetic field. In a
crude sense, TOF is similar to chromatography, except there is no stationary/ mobile phase,
instead the separation is based on the kinetic energy and velocity of the ions [19-20].
3.4.2. Detector system:
As ions hit the surface they are converted to electrons. They ensure high sensitivity and low
background noise. They are expensive. Light sensitive. Depending on usage last for 6-18
months. Once the ions are separated by the mass analyser, they reach the ion detector,
which generates a current signal from the incident ions [21-23].
The most commonly used detectors in MS are as follows:
Faraday cup.
Electron multiplier.
Photomultiplier dynode.
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1. Faraday cup:
TOF Analysers separate ions by time without the use of an electric or magnetic field. In
a crude sense, TOF is similar to chromatography, except there is no stationary/ mobile
phase, instead the separation is based on the kinetic energy and velocity of the ions [24].
Figure 10. Faraday cup.
2. Electron multiplier:
It is the most common means of detecting ions. It is made up of a series (1 to 24) of
aluminium oxide (Al2O3) dynodes maintained at ever increasing potentials. Ions strike
the first dynode surface causing an emission of electrons. These electrons are then
attracted to the next dynode held at a higher potential and therefore more secondary
electrons are generated. Ultimately, as numerous dynodes are involved, a cascade of
electrons is formed that results in an overall current gain on the order of one million or
higher. The high energy dynode (HED) uses an accelerating electrostatic field to increase
the velocity of the ions and serves to increase signal intensity and therefore sensitivity [25].
Figure 11. Electron multiplier.
3. Photomultiplier dynode:
The photomultiplier conversion dynode detector is not commonly used. It is similar to
electron multiplier in design where the secondary electrons strike a phosphorus screen
instead of a dynode. The phosphorus screen releases photons which are detected by the
photomultiplier and are then amplified using the cascading principle. One advantage of
the conversion dynode is that the photomultiplier tube is sealed in a vacuum, unexposed
to the environment of the mass spectrometer and thus the possibility of contamination is
removed [26].
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Figure 12. Photomultiplier dynode
4. Sample Preparation of LA-ICP-MS:
In general sample preparation is straightforward. Polishing is usually necessary if the electron
microprobe is to be used before loading the sample into the sample cell.
Because the laser sample cell is not under vacuum, outgazing of the support material is not a
problem [27].
Powdered samples should be treated in a similar way to XRF (X-Ray Fluorescence) analysis and
stabilised either by
(a) Compacting the sample into a pellet with or without a binding agent, [Fig:(a)].
(or)
(b) Fusing the sample to a borate glass or using a strip heater. [Fig :(b)]
Figure (a). Pellet Preparation. Figure (b). Fusing of sample.
5. Applications:
Laser ablation has been applied to the determinations of the trace element concentration in a wide
range of materials in many different studies, including volcanology, petrology, mineralogy, ore
deposits, materials and forensic studies, cultural heritage and environmental sciences. In the
environmental science, LA-ICPMS analyses is applied to a variety of biological structures, such as
tree rings, mollusc shells, otoliths, fin ray and fish scales. This is a consequence of two important
factors:
Analyses of solids by laser requires little (or) no sample preparation;
The determination of trace elements content (or) isotopic composition in almost all types of
materials is achieved at high spatial resolution [28]
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1) Analysis of trace elements in lipsticks:
Each lipstick was analysed by LA-ICP-MS to determine the trace element composition.
Four to five smears of lipstick, around 2.4 cm x 5 mm, were applied to clean Teflon squares
(2.5 x 2.5 cm) for laser ablation. Teflon contains minimal trace metal background and thus
was chosen as the substrate for the lipstick smears. The Teflon squares were soaked in 12%
nitric acid with 18 MΩ·cm Millipore water for a minimum of 48 hours before use. The
nitric acid was prepared by in-house sub-boiling distillation. The lipstick smears were
ablated with a femtosecond laser, the laser in a single line scan pattern. Argon was used as
the carrier gas through the ablation cell. The nominal spot size was ~70 µm. e.g.: 7Li+, 25Mg+,
26Mg+, 27Al+. Etc.
2) Imaging of brain tissues:
Images of C, Cu, and Zn measured on a thin section of rat brain tissue by LA-ICP-MS
obtained in the routine mode are summarized. The shape and structure of these LA-ICP-MS
images are in good agreement with the photograph of the tissue from a similar rat brain
stained with Cresyl violet. The LA-ICP-MS images demonstrate that the distribution of the
two metals and one abundant non-metal is quite different. The 13C+ and 64Zn+ images also
clearly demonstrate the localization of the hippocampus in the rat brain. An interesting
multi-layered structure of the cortex is especially visible in the 63Cu+ image.
Figure 13. Imaging of brain tissues.
3) Analysis of soil:
Reference materials: Five Certified Reference Materials: two soils, two lake sediments, and
one stream sediment, were used to determine the best sample preparation method for LA-
ICP-MS of soil samples.
Pellet preparation:
• Pellets without binder: Well homogenized samples were pressed into a pellet of 1.2 cm
diameter and 2 mm height.
• Pellets with boric acid: Pellets with boric acid were prepared as described. This approach
has been developed for ED-XRF analysis of soils. The samples (0.1 g) were mixed with
H3BO3 ratio 1:5, well homogenised and pressed into pellets. Blank pellets, containing only
boric acid were prepared in the same way.
• Pellets with organic solvents: To a soil sample (0.6 g) placed in an agate mortar, 1 ml of
hexane is added. The mixture is stirred for 10 min and dried in a heater block at 50oC.
Afterwards, 1 ml of dichloromethane is added, stirred for 10 min and dried in a heater block
at 50oC. Soil pellets are prepared as described above.
Determined isotopes:7Li, 23Na (0.013), 24Mg (0.013), 27Al (0.015), 28Si (0.017), 31P (0.012), 39K (0.016), 42Ca (0.013), 47,49,50Ti (0.012), 51V,52,53Cr.
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4) Ornithology:
The elemental (Cd, Cu, Pb, Pd, Pt, Rh and Zn) profiles along feather shafts of various bird
species in Sweden, namely, peregrine falcon (Falco peregrinus), sparrowhawk (Accipiter
nisus), willow grouse (Lagopus lagopus) and house sparrow (Passer domesticus) were
investigated by LA-ICP-MS. For analysis, the feathers were cut to lengths of 3–4 cm and
fixed on sticky tape without additional preparation. A line was ablated along shaft sections
using a spot size of 50–100 mm using a laser energy of 0.7–0.8 mJ, a repetition rate of 20
Hz, and a translation rate of 20 mms. Internal standardisation using the Ca signal intensity
was employed. Ablation of feathers revealed that Pb, Cu and Cd levels were highest in
urban habitats. The profile of Pt, Pd and Rh showed that contamination of feathers consists
almost exclusively of externally attached particles. The highest total metal concentrations
were found to be in the feathers of sparrowhawk and house sparrow because of their urban
habitats.
5) Marine studies:
Elemental analysis of marine samples is still a major area of research utilising LA-ICP-MS,
primarily for providing a chemical archive of environmental changes by the analysis of
shells, coral and fish otoliths.
Coral samples were cut into 45×25 mm sections and cleaned with pure water. The outer
tissue surface was then cleaned with ultrasonic agitation in a 30% hydrogen peroxide
solution and again in water, and dried at 41oC.
The samples were preablated at a repetition rate of 50 Hz and a laser energy of 100 mJ
using pulses from a 193-nm ArF excimer laser. A VG Elemental PG2+ICP-MS was used
for the analyses.
To obtain representative sampling over the structural elements of the coral a mask of 100
mm parallel to the growth axis by 500 mm (perpendicular to the growth axis) was found to
be essential.
For analysis, the laser was pulsed at 10 Hz at 100 mJ. Rare earth elements (La, Ce, Pr, Nd,
Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using the same laser system
at a repetition frequency of 20 Hz but with an Agilent 7500s mass spectrometer. [29-30]
6. Conclusion:
LA-ICPMS is a fast and effective characterization technique for trace element analysis of solid
samples. Although the laser-material interaction is complex, it was observed that an increase in the
fluence, repetition rate and spot size can increase the signal intensity for an element at the ICP-MS.
Impurity concentrations were measured at the grain boundary and grains for high-performance
multi-Si wafers and it was found that ablated grain boundaries contain higher concentrations of
metals, which could have resulted from preferential segregation of impurities at grain boundaries
during crystal growth. Lifetime samples fabricated from standard p-type multi-Si show spatially
non-uniform degradation characteristics during LID. Spatial trace element analysis was performed
on two regions that differed in their response to light induced degradation.
7. Acknowledgement:
I would like to thankful to our college “RBVRR Women’s college of pharmacy” for giving me this
great opportunity.
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8. References:
[1]. R. Idegawa et al., M. Ohata et al., N. Furata et al., and K. Satake et al., Bunseki Kagaku et al.,
2001, 50 vol (6), pp. 441–446.
[2]. D. Lugo et al., Y. Cai et al., M. J. Lynn et al., K. Downum et al., and P. Blackwelder et al.,
Abstr. Pap. Am. Chem. Soc., 2002, pp. 223-226
[3]. S. F. Boulyga et al., M. Tibi et al., and K. G. Heumann et al., Anal. Bioanal. Chem., 2004, 378,
pp. 342–347.
[4]. M. D. Seltzer et al., Appl. Spectrosc., 2003, 57 vol (9), pp. 1173–1177.
[5]. Y. L. Lee et al., C. C. Chang et al., and S. J. Jiang et al., Spectrochim. Acta, Part B, 2003, 58
vol (3), pp. 523–530.
[6]. S. F. Boulyga et al., D. Desideri et al, M. A. Meli et al, C. Testa et al., and J. S. Becker et al.,
Int. J. Mass Spectrom., 2003, 226 vol (3), pp. 329–339.
[7]. T. Okuda et al., J. Kato et al., J. Mori et al., M. Tenmoku et al., Y. Suda et al., S. Tanaka et al.,
K. B. He, Y. L. Ma, F. Yang, X. C. Yu, F. K. Duan and Y. Lei et al, Sci. Total Environ., 2004, 330
vol (1–3), pp. 145–158.
[8]. Taylor et al., Blaney et al., D.L et al., and Cardell et al., 2000. Elemental fractionation in
ultraviolet laser ablation sampling of igneous silicate minerals relevant to Mars. Applied Surface
Science, 165 pp. 166-177.
[9]. M.F. Thirlwall et al., and A.J. Walder et al., (1995) In situ hafnium isotope ratio analysis of
zircon by inductively coupled plasma multiple collector mass spectrometry, Chemical Geology,
122: pp. 241-247.
[10]. Russo, R.E. et al., X. Mao et al., and O.V. Borisov et al., (1998) Laser ablation sampling.
Trends in Analytical Chemistry 17, pp. 461-469.
[11]. R.E. Russo et al., (1995) Laser Ablation, Applied Spectroscopy, 49 pp. 14-28.
[12]. R.E. Russo et al., X. Mao et al., M. Caetano et al., and M.A. Shannon et al., (1996)
Fundamental characteristics of laser-material interactions (ablation) in noble gases at atmospheric
pressure using inductively coupled plasma-atomic emission spectroscopy, Applied Surface Science,
96, pp. 144-148.
[13]. Russo, R.E. et al., Mao, X.L. et al., Liu, H.C. et al., Yoo, J.H. et al., and Mao, S.S. et al., 1999.
Time-resolved plasma diagnostics and mass removal during single-pulse laser ablation. Appl.
Phys., A69 pp. 887-894.
[14]. H. Scholze et al., E. Hoffmann et al., C. Ludke et al., and A. Platalla et al., (1996) Analysis of
leaves by using the laser ICP-MS with isotope dissolution method, Fresinius Journal of Analytical
Chemistry, 355: pp. 892-894.
[15]. H. Scholze et al., H. Stephanowitz et al., E. Hoffmann et al., and J. Skole et al., (1994)
Element analysis of inhomogeneous samples by laser ablation, Fresinius Journal of Analytical
Chemistry, 350, pp. 247-252.
Journal of Information and Computational Science
Volume 9 Issue 12 - 2019
ISSN: 1548-7741
www.joics.org460
[16]. Scott, D.J. et al., (1999) U-Pb geochronology of the eastern Hall Peninsula, southern Baffin
Island, Canada: a northern link between the Archean of West Greenland and the Paleoproterozoic
Torngat Orogen of northern Labrador. Precambrian Research 93, pp. 5-26.c
[17]. Shaohai, C., et al. (1998) Trace element characteristics in the diopsides of peridotite
xenoliths; a laser ablation-inductively coupled plasma-mass spectrometry study. Chinese Science
Bulletin 43, pp. 579-583.
[18]. T.J. Sheppherd et al., and S.R. Chenery et al., (1995) Laser ablation ICP-MS elemental
analysis of individual fluid inclusions: An evaluation study, Geochimica Cosmochimica Acta, 59,
pp. 3997-4007.
[19]. Shibata, Y. et al., Yoshinaga, J. et al., and Morita, M. et al., 1993. Micro-laser ablation system
combined with inductively coupled plasma mass spectrometry for the determination of elemental
composition in the micron range. Analytical Sciences, vol-(9), pp. 129-131.
[20]. Shibuya, E.K., et al. (1998) Determination of platinum group elements and gold in geological
materials using an ultraviolet laser ablation high-resolution inductively coupled plasma mass
spectrometric technique. Journal of Analytical Atomic Spectrometry 13, pp. 941-944.
[21]. Shuttleworth, S. et al., and D.T. Kremser et al., (1998) Assessment of laser ablation and
sector field inductively coupled plasma mass spectrometry for elemental analysis of solid samples.
Journal of Analytical Atomic Spectrometry 13, pp. 697-699.
[22]. Siddaiah, N.S. et al., and A. Masuda et al., (1997) Preconcentration of noble metals in
geological and environmental samples: a nickel sulfide Mini-bead technique. Proceedings of the
Japan Academy Series B-Physical & Biological Sciences 73 B, pp. 13-18.
[23]. Sie, S.H. et al., (1997) Nuclear microprobe in geological applications - where do we go from
here. Nuclear instrument and methods in Physics Research 130B, pp. 592-607.
[24]. D.J. Sinclair et al., and M.T. McCulloch et al., (1997) The coral record of terrestrial fluxes
into the Great Barrier Reef: Analysis of trace elements in inshore corals by laser-ablation ICP-MS,
RSES Annual report, pp. 138-139.
[25]. D.J. Sinclair et al., L.P.J. Kinsley et al., and M.T. Mcculloch et al., (1998) High resolution
analysis of trace elements in corals by laser ablation ICP-MS. Geochimica et Cosmochimica Acta
62, pp. 1889-1901.
[26]. R. Stalder et al., S.F. Foley et al., G.P. Brey et al., L.M. Forsythe et al., and I. Horn et al.,
(1997) First results from a new experimental technique to determine fluid/solid trace element
partition coefficients using diamond aggregate extraction traps, N Jb Miner Abh, 172: pp. 117-132.
[27]. A.A. Van Heuzen et al., and J.B.W. Morsink et al., (1991) Analysis of solids by laser ablation -
inductively coupled plasma - mass spectrometry (LA-ICP-MS) - II. Matching with a pressed pellet,
Spectrochimica Acta, 46B, pp. 1819-1928.
[28]. Stix et al., G. Gauthier et al., and J. Ludden et al., (1995) A critical look at quantitative-laser-
ablation ICPMS analysis of natural and synthetic glasses. Canadian Mineralogist 33, pp. 435-444.
[29]. S.J. Stotesbury et al., J.M. Pickering et al., and M.A. Grifferty et al., (1989) Analysis of
lithium and Boron by inductively coupled plasma mass spectrometry, Journal of Analytical Atomic
Spectrometry, vol-(4) pp. 457-460.
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[30]. P. Sylvester et al., and M. Ghaderi et al., (1997) Trace element analysis of scheelite by laser
ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) using a synthetic silicate
glass standard, Chemical Geology, 141, pp. 49-65.
Journal of Information and Computational Science
Volume 9 Issue 12 - 2019
ISSN: 1548-7741
www.joics.org462