ULaval News
Donate
Faculty portal
monPortail
Contact us
Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICPMS) Agilent 8900 Triple Quadrupole
In situ analysis of trace elements and sulfur isotopes
LA-ICP-MS enables in situ analysis of trace elements in minerals and other solid materials, as well as the analysis of sulfur isotopes in sulfides . Analyses can be performed as spot analyses, profiles, or maps to characterize the spatial distribution of elements. Thanks to the Agilent 8900 Triple Quadrupole Spectrometer, its collision-reaction cell, and the RESOlution laser system, spectral interferences are better controlled and resolved, improving the selectivity and reliability of the results. The instrument offers a spatial resolution of 2 to 100 µm and detection limits that can be below 1 ppm.
4
Availability and contact
3
User Fees
2
Sample types
1
Technique and applications
LA-ICP-MS combines a laser ablation system, an inductively coupled plasma source and a mass spectrometer. The laser removes a microscopic amount of material directly from the surface of a solid; the resulting aerosol is transported to the plasma, converted into ions, separated according to their mass-to-charge ratio and then measured by the detector. This analytical chain provides localized elemental or isotopic information, with a spatial resolution generally ranging from a few micrometres to a few tens of micrometres, depending on the method.
1 | Laser Ablation and Aerosol Formation
The sample is placed in a closed cell and viewed by camera in order to select a mineral, an inclusion, a zone or a microstructure. A pulsed laser is focused through lenses and mirrors. When the fluence exceeds the ablation threshold, each pulse causes ultrafast heating, local melting or vaporization, and the ejection of particles and vapour. The ablated material forms an aerosol that is carried by a flow of helium, sometimes mixed with argon, to the ICP torch. A small beam improves spatial resolution but reduces the mass ablated and the signal; a larger beam increases sensitivity at the cost of a larger analyzed volume.
Technique and applications
Sample types
The laser ablation system is equipped with several sample holders allowing the analysis of substrates of different sizes and shapes. The sample surface should preferably be flat; light polishing is generally required.
Solid samples
Solid, compact and massive materials, such as rocks, metals, concrete, etc., are prepared in the form of thin sections (standard size of 46x27mm) or polished sections (diameter and height up to 30mm).
Non-cohesive materials
Soils, powders, ashes, mineral concentrates and other non-cohesive materials can be analyzed after encapsulation in a compatible resin followed by polishing to obtain a flat surface.
Samples with unusual dimensions
A sample holder allows for the placement of large or irregularly shaped solid fragments. The target area must be accessible to the beam, sufficiently flat, and compatible with the ablation cell. Sample compatibility and the feasibility of the analyses must be validated by the MicroLab team.
Impact of sample preparation on quality and repeatability
A flat surface facilitates laser focusing and maintains a consistent geometry. A rough, inclined, porous, or unstable surface can alter the effective crater diameter, the ablated mass, and aerosol transport. Slight variations in these parameters generally result in signal changes that do not reflect the sample's chemical composition. Uniform and proper preparation ensures the repeatability of measurements on both samples and reference materials. If conductive coatings have been previously applied for preliminary electron microprobe (EPMA) or scanning electron microscopy (SEM) analyses, these must be removed from the ablated area to prevent signal contamination.
COMPATIBLE SAMPLES
Sample types
Click an image to enlarge it
User Fees
MicroLab rates are set according to the type of user, the instrument usage mode and, depending on the service, the analysis time or the number of samples. Some services, particularly sample preparation, may be billed per sample, while instrument use and data processing are generally billed on an hourly or daily basis.
User Categories
Université Laval
This category includes users whose projects are funded, in whole or in part, by Université Laval, regardless of their faculty or affiliated unit. In particular, it includes undergraduate, master’s and doctoral students carrying out work as part of a research project supervised by a Université Laval professor or researcher.
Research / Public Funding
This category includes students, professors, researchers and professionals from other Canadian universities, CEGEPs or research centres, when the work is carried out as part of projects funded primarily by public funds. These funds may come, for example, from government or para-governmental organizations, federal or provincial research programs, or other public funding sources.
Industry
This category applies to private companies and to work carried out in an industrial or commercial context.
Usage Modes
When several usage modes are offered for an instrument, rates distinguish between assisted and unassisted use.
Assisted
The instrument is operated by the lead operator or the technical manager, who is responsible for starting the analysis, changing samples when necessary and assisting the user through the various stages of the measurement. This mode is particularly suited to analyses requiring specific instrumental expertise and to occasional users.
Unassisted
After completing appropriate training, users can carry out their own analyses and, when necessary, change samples themselves. Use nevertheless remains under the supervision of the instrument manager. Initial training is billed according to the time required and includes both staff time and instrument use.
Unassisted use is restricted to Université Laval users and depends on the instrument, the type of analysis and the user's level of experience. For the conditions of access to this mode, please contact the manager of the relevant instrument.
Pricing Based on Analysis Duration
For services with hourly and daily rates, billing is based on the total instrument usage time, including the time required to prepare and configure the instrument for the analysis.
For periods under 6 hours, the hourly rate applies. From 6 hours up to 24 hours, a daily flat rate applies. Beyond 24 hours, billing continues in daily increments at the applicable daily rate.
The daily flat rate is particularly advantageous for long analyses: its cost generally corresponds to that of six hours of use, while allowing the instrument to be used for up to 24 hours. For example, an analysis lasting 12, 18 or 24 hours is billed at the same daily flat rate rather than as the sum of the individual hours.
Services listed “per sample” are billed according to the number of samples processed, regardless of this hourly/daily structure.