Rapid stoichiometric analysis of calcium‑phosphorus ratio on hydroxyapatite targets by one-point calibration laser-induced breakdown spectroscopy

• Published in: Spectrochimica acta. Part B: Atomic spectroscopy Vol. 184; p. 106250
• Main Authors: Gomes, G.C., Borges, F.O., Borghi, F.F., Cavalcanti, G.H., Martins, C.M.S., Palleschi, V., Mello, A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.10.2021; Elsevier BV
• Subjects: Absorption spectroscopy; Analytical methods; Atomic absorption spectroscopy; Automation; Bioceramics; Biocompatible material; Biomedical materials; Bone composition; Calcium; Calcium phosphates; Calibration; Deposition; Fluorescence; Hydroxyapatite; Laser induced breakdown spectroscopy; Lasers; Metals; One-point calibration LIBS; Phosphates; Phosphorus; Prostheses; Prosthetics; Quantitative analysis; Sample preparation; Spectral analysis; Spectrum analysis; Stoichiometry; X-ray fluorescence; Laser-induced breakdown spectroscopy; One-point calibration LIBS; Quantitative analysis; Biocompatible material
• ISSN: 0584-8547; 1873-3565
• DOI: 10.1016/j.sab.2021.106250

The calcium‑phosphorus ratio (Ca/P) has an important role in calcium phosphate applications, as a slight change in this ratio results in substantial modifications of their characteristics. Hydroxyapatite is a bioactive ceramic of the calcium phosphate family, and its composition and crystalline structure are similar to the human bone. For this reason, it is widely used to promote bone integration in prosthetics and scaffolds. Prosthetics are usually made of metal and coated with bioceramics and the some techniques used to make these coatings depositions conserve the stoichiometry from the target during deposition. Therefore, studying the target Ca/P is a way to guaranteeing the final deposition stoichiometry. In this study, we investigated the One Point Calibration – Laser Induced Breakdown Spectroscopy (OPC-LIBS) method for the measurement of the Ca/P of hydroxyapatite targets. This method is quantitative, based on the determination of correction parameters via analysis of a standard sample with known stoichiometry. Results were compared to well-established techniques of X-ray Fluorescence (XRF) and Atomic Absorption Spectroscopy (AAS) and showed that the deviation in the difference is less than 5%, proposing a substitute for elemental analysis. Moreover, this method has technical advantages such as rapid measurements, no need for sample preparation or destruction and easy automation. [Display omitted] •OPC-LIBS method applied to bioactive ceramic quantitative elemental analysis.•Validation of the OPC-LIBS method as a fast and reliable quantitative analytical technique.•One standard of known composition is needed for the quantitative analysis.•The Ca/P ratio amounts have been used to determine the ceramic samples stoichiometry.•The great advantages of the method are fast measurements, no need for sample preparation or destruction and easy automation.