Can You Create Your Own Reference Materials For ICP Calibration?
Calibration is an essential part of analytical chemistry because it enables scientists to check equipment is functioning correctly and produces accurate results. With regard to inductively coupled plasma (ICP) spectroscopy, this analytical method is used to identify major compounds and trace elements in chemical samples by ionising them. Once ionised, ions are separated according to their mass-to-charge ratios, and the concentration of each element can be determined. Without calibrating ICP spectrometers, analysis results could be inaccurate or contaminated, leading to further problems such as unsafe laboratory equipment and unreproducible data.
For ICP calibration to be successful, reference materials are required and serve as a benchmark for accurate results. Without these materials, it would be difficult to know whether the ICP calibration is completed accurately, thus impacting the spectrometer and analyses it is used in. Reference materials for ICP calibration can be challenging to source, which leads us to the question: can you create your own materials for ICP calibration? Throughout this blog post, we will explore the possibilities and provide an answer to this question.
Understanding ICP Calibration
Before we look at DIY reference materials in more detail, let’s briefly examine how ICP calibration works. When analysing samples with ICP spectroscopy, the concentration of an element is measured by a detector that counts how many ions pass through per second. This detector is used again in ICP calibration. Firstly, a calibration curve is constructed using reference standards. Secondly, the signal measured by the ICP detector is converted into a concentration value by the calibration curve. The curve is produced using known concentrations of elements, which can then be used to calculate the concentration of analytes in unknown samples.
Learn more about ICP spectroscopy here
Challenges in Obtaining Reference Materials
Although commercial reference materials are the standard choice for ICP calibration, some scientists consider creating their own a reasonable option due to their challenges in obtaining suitable materials. The key problems you may encounter include the availability, cost, and quality of reference materials for ICP calibration. Availability can be problematic for several reasons, including stock levels, specific applications, and global influences, which can also have a knock-on effect on price. The quality of reference materials is critical in any application because calibration will only be conducted correctly if they are reliable and reproducible. Finally, reference materials can be expensive. Individually or in combination, these challenges often lead to the question, ‘Can I create my own reference materials?’.
In short, the answer is yes, you can. However, creating your own reference materials can be costly, time-consuming, and challenging.
Creating Your Own Reference Materials
With careful planning and the right resources, you can consider a DIY approach to reference materials. However, any errors made during the process can have severe consequences for calibration and future experiments. Before we briefly look at methods of producing your own reference materials, it is important to mention the additional reference standards you will need to use to ensure traceability for each material you produce.
The hierarchy of reference materials is as follows:
- National Metrology and other primary standards
- Certified Reference Materials (CRMs)
- Reference Materials (RMs)
- Analytical Standards
- Research Chemicals
So, if you decide to create your own reference materials, you must obtain CRMs or national metrology standards that suit your applications. Traceability and certification are crucial for reference materials, ensuring accuracy, reliability, and reproducibility.
There are several methods of developing your own reference materials, including mixing and dilution techniques. Regardless of the process used, there are some key considerations. To start with, consider what validated methods are available, the materials required, and identify relevant analytes. Additionally, the amount of material and method of preparation is also crucial.1
Where Can I Find the Reference Materials I Need?
XRF Scientific develops reference materials for a range of analytical chemistry applications, including XRF and ICP spectroscopy. Purchase from us to ensure your reference materials are suitable for calibrating your ICP instruments, as well as saving yourself from the complex process of producing them yourself.
Contact XRF Scientific today for a quote or more details about our ICP calibration reference materials.
References and Further Reading
- https://www-pub.iaea.org/MTCD/publications/PDF/te_1350_web.pdf
