X-ray diffraction (XRD) is a non-destructive laboratory technique that assesses the lattice spacing of crystalline solids . Lattice spacings and distortions can be used to identify elastic properties, residual stresses, and the identities of unknown materials in a sample . XRD can help characterize critical material properties for information on how a material might interact with biological tissue upon implantation. XRD collects lattice spacing by shooting an X-ray into a crystalline solid at a known wavelength, λ, and a known angle, θ, and then gathering the intensity of the collected refracted X-ray . When shooting the X-ray at the crystal, part of the beam will pass through the atomic plane, and part will hit a lattice and refract back into the diffractometer, which measures the intensity of the refracted beam . The angle that the X-rays are fired into the sample, with a range of angles from 0 – 90° . The X-ray beam is rotated so that different atomic planes can be activated; firing at 20° may not hit an atomic plane and the entire beam might pass through, whereas firing at 65° may hit the lattices on the atomic plane and refract the beam towards the diffractometer . XRD has many advantages when being used for the characterization of a biomaterial, as XRD is typically non-destructive and does not require a vacuum to function.
The powdered technique of XRD involves the irradiation of a powdered crystalline material to identify different (hkl) miller indices from different lattice spacings throughout the sample . The intensity readings correspond uniquely to a specific element; the powdered technique allows the identification of elements present in the sample by identifying the miller indices and atomic spacings of the element present, which are unique to that element . If a sample contains more than one material, there will be multiple intensity readings that can be used to identify the present elements . This technique can prove especially useful with material intended for medical use, as biomaterials are typically some sort of composite involving a mixture of elemental compositions which can all be identified with XRD. XRD is not only time-effective, but it is often cost-effective as well when considering the costs of electron microscopy, which can provide similar information. XRD is a convenient and effective solution for characterizing materials for use in medical devices, biomaterials, drug delivery solutions, and more.
Are you struggling to get your device or drug FDA approved? Give EMMA International a call today at 248-997-4497 or email firstname.lastname@example.org to learn which regulatory pathway is right for your product. We specialize in full-circle consulting to help get your product approved and out to market in the best way possible.
 – Wang, A.N., Chuang, C.P., Yu, G.P., & Huang, J.H. (2014). Determination of average X-ray strain (AXS) on TiN hard coatings using cos2αsin2ψ X-ray diffraction method. Surface & Coatings Technology 262, 2015 (40-47). http://dx.doi.org/10.1016/j.surfcoat.2014.12.009
 – Kasap, S.O. (2006). Principles of Electronic Materials and Devices 3rd ed. p.(848-852). ISBN 0-07-295791-3