The advent of Inductively Coupled Plasma Mass Spectrometry, or ICP-MS, changed the world of element analysis forever. It quickly became a major analytical technique in industrial laboratories. There is a reason why many labs are still using this method. It offers great precision, making it the best choice for many types of analysis.
Here’s everything you need to know.
ICP-MS Defined
ICP-MS stands for Inductively Coupled Plasma Mass Spectrometry and is a method of analysis of organic and inorganic compounds which involves passing a beam of ions through a controlled gas, usually helium, in a closed, evacuated chamber. It is an ionizing detector that can separate molecules into different components through a plasma.
The ICP-MS apparatus consists of two major parts: the sample introduction unit or SIU and the mass spectrometer. It was popularized by R.S. Houk in the year 1980 and was launched into the market in 1983. Its ability to provide information on the precise chemical compounds in a sample makes it an essential tool for various research projects.
Fundamentals of ICP-MS
Listed below are the six fundamentals of ICP-MS and how it works.
1. Sample introduction system
2. Interface
3. Ion Optics
4. Inductively coupled plasma (ICP)
5. Mass Analyser
6. Detector
First, the fluid is atomized into the introduction system sample. A good aerosol is then created and transmitted to an argon plasma. Then, the liquid sample atomized by the plasma is extracted into electrostatic lenses or ion optics, guiding the beam of ions to the quadrupole mass analyser. The ions are then separated based on mass-charge ratio and measured using the detector.
Where To Use ICP-MS?
ICP-MS rapidly and reliably measures a wide range of elements in many samples. It can also measure elements generally present at very low levels in a sample and have relatively large detection limits.
Speciation Analysis
Speciation analysis is the process of separating and quantifying the chemical forms of an element. During this process, varying ion mixtures are separated into different chemical forms using techniques such as chromatography. The ICP-MS detects each chemical form as normal but identifies different chemical forms according to how much energy it needs to separate ions.
Gas Analysis
ICP-MS gas analysis can monitor the composition of volatile organometallic compounds in natural gas. The technology also provides an alternative method for determining terpene content.
Solid Sample Analysis
The LA-ICP-MS direct solids analysis method is a promising, low-cost method for analyzing fresh and frozen samples. Connecting a laser ablation device to an ICP-MS allows you to perform direct samples with less sample preparation, allowing analyses without further chemical extraction or filtration.
Liquid Sample Analysis
In liquid calibration and preliminary analyses, liquid samples are introduced into the instrument using a filtered sample introduction nozzle. This is the most common way to introduce ICP-MS samples for all precision techniques except for HF or HF/IF.
How To Perform ICP-MS?
- The hardware configuration and accessories you choose should match the sample type and analysis required.
- You must check your instrument is in good working order before starting the analysis by ICP-MS. Your instrument may need maintenance, or it may be out of calibration.
- Be sure to prepare the samples using methods appropriate to the element and its chemical stability. For instance, if you’re working with a water sample, acidification may be required to stabilize the sample.
- Find ways to optimize the instrument and check whether it works well.
- The first step in the analysis of a preparation solution is to set up the method. This includes choosing the appropriate internal standard, preparing the filter solutions, calculating the correct amount of sample mass to be measured in your reaction cell, and determining the flow rate and other setup parameters required to meet your experiment goal and requirements.
- For every measurement, you should verify that the setup and run order are correct and that the vial positions are correct.
- Before reporting the results, check the QC results through the ICP -MS software or a laboratory information management system (LIMS).
Conclusion
ICP-MS is a highly versatile technique used in a wide range of applications and is an important tool for analyzing elements. Its continued development will continue to allow it to grow and adapt, providing a robust and reliable method for many years.
