Evaluation of the quantitative performance of different spectroscopic techniques for multielemental analysis of nail and hair samples: A comparative study

Background

The accurate detection and quantification of elemental content in skin appendages, such as, hair and nails are pivotal in biomedical research, including disease diagnostics, environmental exposure monitoring, and forensic investigations.

Methods

This study evaluates and compares the suitability of different sample treatments and four spectroscopic techniques—Energy Dispersive X-ray Fluorescence (EDXRF), Total Reflection X-ray Fluorescence (TXRF), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) for multielemental analysis of these biological tissues. Making use of different Certified Reference Materials (CRMs), the performance of the developed methods was assessed based on their sensitivity, precision, range of detectable elements, and the extent of sample preparation required.

Results

EDXRF method is suited for rapid and non-destructive determination of light elements present at relatively high concentrations – Sulfur (S), Chlorine (Cl), Potassium (K) and Calcium (Ca) – in hair and nail samples. TXRF provides information of most of the elements present in the target samples, including Bromine (Br), but the determination of light element (i.e, Phosphorus (P), S, Cl) is not feasible. Finally, the proposed ICP-OES/ICP-MS method is useful for the determination of major, minor and trace elements, except chlorine.

Conclusion

This comparative study reveals the distinct strengths, range of elements and suitable applications of each technique, providing a valuable framework for selecting appropriate methods based on specific analytical needs.