Laser Ablation Inductively Coupled Plasma Mass Spectroscopy: Not Just Rocks

Spots are typically less than 100 um, often 20 um or less in these applications. Note that smaller spots are possible, even down to 1um, but the amount of material removed for analysis is also reduced so you also need to consider how this affects sensitivity on your ICP.

Cell washout time is variable. We can optimize from over 1 second to a full pulse sent through the system in 1ms simply by modifying gas flows and adding a piece or two of glassware on the back of the ICP torch.

If you are interested in elemental concentration in layers of plastic then a laser system can either analyze each layer in turn by gently rastering the surface, or by drilling a hole and removing material with each laser shot. Each individual laser shot would remove only a few nm of material. The success, or otherwise, of this application would depend on what needs to be measured and at what concentrations, but in principle it should be possible.

The short answer is yes, it can. LA ICP MS has been successfully used in the past for the analysis of dried blood, serum, wine, beer, coffee, etc. There’s in fact a paper titled “Radial linescans as representative sampling strategy in dried-droplet laser ablation of liquid samples deposited on pre-cut filter paper disks” which discusses various protocols to be used in order to make sure that the ablation of a dried liquid droplet is representative of the chemical composition of the solution used. Naturally, the initial concentration of the dried solution is essential in establishing the limits of detection and quantification, but since the modern laser ablation systems can quickly ablate large areas, one can fully ablate an entire dried droplet in a matter of seconds to minutes, hence increasing the amount of sample that is delivered to the ICP to be measured. With the appropriate hardware and a well developed analytical method, the LOD can be in the single digit ppm range, and even below that in some cases.

The sample chamber itself measures 100mm x 100mm and allows for the placement of a modular drawer design that can be outfitted to meet your specific sample needs. One of the insert options is an open chamber that allows for the placement of larger samples and measures 100 mm x 2.75” (~69.85mm).

The depth of the ablation craters are ordinarily measured in nanometers as each “shot” of the laser results in nanometers of material being removed. How much material is dependent upon a number of factors such as the ablated matrix and the power with which the laser is operating. On the other end of the spectrum, the crater depth can increase to ~3x the width of the crater. Beyond that depth, the ejected material begins to have trouble escaping the crater and often times hits the wall and falls back to the bottom to be re-ablated. This can have serious ramifications on data quality.

Traditionally, samples have been mounted within an epoxy resin and polished to provide a flat surface but this is largely because laser ablation was a geo-centric tool in its infancy. Other sample mounts are certainly possible including the use of thin section mounts, glass slides for biological sample analysis and even an open chamber that allows for the placement of larger or irregularly shaped samples that the user may not wish to mount or polish (e.g. meteorites or archeological samples). These irregularly shaped samples are sometimes placed within the open sample chamber using a piece of putty or the placement of glass beads/sand in the bottom of the drawer to help with placement and also help eliminate unnecessary dead-volume.

Yes. LA-ICPMS is a fully quantitative technique and, when performing mapping applications, each pixel (in all three directions) contains all of the elemental data acquired by the ICPMS. Of course, it being quantifiable depends upon the quality and matrix-match of the utilized standards but, rest assured, Teledyne’s HDIP software provides an automated solution to perform the quantitation and interrogate the data.

A single laser pulse can remove a few nanometers to tens of nanometers from a sample’s surface, depending on the laser used and how the lasing parameters are selected. This means that LA ICP MS is well suited for the analysis of coatings and thinly deposited films. We have quite a few users around the world who are routinely performing paint analysis on different matrices (metal, glass, ceramics, polymers) as well as various other coatings applied on metals and polymers.

Lithium is the lightest element that can be reliably measured using LA ICP MS techniques. The limit of detection is largely dictated by the ICP MS used in conjunction with the laser, but certainly the laser can provide enough sample for a sensitive ICP MS instrument to be able to measure Li in below ppm range.

The name of the company is myStandards GmbH. They can be found at the following URL:
https://www.my-standards.com/en/.

Technically the answer is yes although only on a micro-scale. As the typical spot used for ablation is 50um, or less, the vast majority of most samples is still available for analysis by other techniques. The exception to this is with biological samples which are ablated from a glass slide and often ablated in their entirety in order to maximize sensitivity.

The short answer is “yes” although there are a number of considerations to be made. The more thorough answer would be that although it’s possible to ablate liquids, LA-ICPMS is seldom the best analytical tool for their analysis and would likely be a costly, and less accurate technique than others available. In the event that you have a sample type that you think would benefit from the technique or you have other reasons for wishing to determine if LA-ICPMS may be a good fit for your analysis, the team at Photon Machines is always happy to discuss and offer advice as to applicability