Can You Create Your Own Reference Materials for XRF Calibration?
X-ray fluorescence (XRF) is a widely used analytical technique that offers powerful analysis in many fields, with environmental science, geology, and materials science being key. Calibration is crucial for XRF instruments because it ensures they can be used to take accurate measurements and produce reliable results based on a sample. This calibration is conducted with reference materials, which are highly characterized samples of a known composition used to evaluate processes and product performance.1
The question is often asked whether scientists can create their own reference materials, and the answer is more complex than some would like. Throughout this blog post, we will answer the question of whether you can create your own reference materials for XRF calibration.
Understanding XRF Calibration
XRF calibration is vital for analytical chemistry and is a process that must be completed accurately, but first, let’s take a quick look at what XRF is. X-ray fluorescence is a non-destructive analytical technique used to determine the chemical and elemental composition of a wide range of samples. It does this by exciting a sample with a primary X-ray source and then measuring the fluorescent X-rays emitted. Each sample will contain elements that emit unique fluorescent X-rays, like fingerprints, enabling them to be analyzed.
Accurate and reliable XRF measurements can only be obtained if the instruments used are calibrated correctly, which happens through calibration. XRF instrument calibration requires a relationship to be established between the elemental composition of a sample and the intensity of X-rays the sample emits, and then a calibration curve is produced. The calibration curve is used to identify the elemental concentration of unknown samples.
Developing Your Own Reference Materials
Although many reference materials are commercially available, there can be difficulties in sourcing ones that match the required sample matrix and concentration range. When reference materials are challenging or costly to source, especially for non-standard matrices, the appeal of creating one’s own increases. Scientists can develop their own reference materials, but it isn’t necessarily an easy task as it requires absolute precision and careful documentation throughout the process, as well as being a costly and time-consuming process.
Producing a reference material requires another material to use as a reference standard, as this will ensure traceability and certification for each level. 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
Therefore, if you are developing your own reference materials, you must have access to the appropriate CRMs or national metrology standards. Without the right standards, the reference materials developed may be inaccurate and unreliable, resulting in many problems for your research and reputation. To answer the question, developing your own reference materials is possible. However, the best way to obtain accurate and reliable reference materials is to work with an accredited reference materials manufacturer.
XRF Scientific and Reference Materials
XRF Scientific understands the challenges scientists face in sourcing or developing their reference materials, so we offer customized options to meet your calibration needs. Our reference materials include fused calibration beads and synthetic iron ore and are developed based on years of practical experience in geological chemistry.
Contact a member of XRF Scientific today to learn more about the importance of using the right reference materials for your research applications.
References
- https://www.sciencedirect.com/science/article/abs/pii/S0149639503800089
