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Published on: June 13, 2015
Characterization of metal composition and molecular weight distribution in Shilajit
Elham Kamgar1, Ange Angaïts2, Joanna Zembrzuska1
1Department of General and Analytical Chemistry, Faculty of Chemical Technology, Institute of Chemistry and Technical Electrochemistry, Poznan University of Technology, Berdychowo 4, Poznan 60-965, Poland.
None:
Shilajit is a complex natural exudate widely used in traditional medicine for its therapeutic value, yet its elemental composition and bioavailability remain poorly understood. Twelve Shilajit samples from diverse geographical origins were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), asymmetrical flow field-flow fractionation (AF4-ICP-MS), and size-exclusion chromatography with UV and ICP-MS detection. Total and water-soluble elemental analyses revealed distinct variability in major metals (Ca and Mg), essential elements (Fe, Zn, Mn), toxic elements (e.g., Co, Ni, Pb, Cd, Hg), and rare earth elements (REEs). Calcium, the most abundant element, was found to be present as a Ca-lactic acid complex by electrospray MS/MS. Toxic metals were present below established toxicity thresholds. Hydrodynamic size analysis indicated that most metals were associated with low-molecular-weight complexes (<10 kDa), corresponding to the elution range of humic acid-metal complexes. Rare earth element distributions followed natural geochemical patterns, suggesting environmental uptake rather than contamination.
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