Characterization of Zinc Carbonate Basic as a Source of Zinc in a Rodent Study Investigating the Effects of Dietary Deficiency or Excess
Keith E. Levine, Bradley J. Collins, Matthew D. Stout, Michael Wyde, Scott E. Afton, Amal S. Essader, Todd J. Ennis, Kelly E. Amato, Andrea C. McWilliams, Brenda L. Fletcher, Reshan A. Fernando, James M. Harrington, Natasha Catlin, Veronica G. Robinson & Suramya Waidyanatha.
Analytical Letters (2017) DOI: https://doi.org/10.1080/00032719.2017.1293073 PMID: Currently Not Available
Zinc deficiency and excess can result in adverse health outcomes. There is conflicting evidence regarding whether excess or deficient zinc in the diet can contribute to carcinogenicity. The objective of this study was to characterize zinc carbonate basic for use as a source of dietary zinc in a rodent toxicity and carcinogenicity study investigating the effects of zinc deficiency and excess. Because of the complex chemistries of zinc carbonate basic compounds, inconsistent nomenclature, and literature and reference spectra gaps, it was necessary to use multiple analytical techniques, including Karl Fischer titration, combustion analysis, inductively coupled plasma–optical emission spectrometry, X-ray diffraction, infrared spectroscopy, X-ray fluorescence spectrometry, and thermogravimetric analysis to characterize the test article. Based on the collective evidence and through the process of elimination, the test article was found to be composed mainly of zinc carbonate basic with zinc oxide as a minor component. The zinc content was determined to be 56.6% (w/w) with heavy metals such as arsenic, cadmium, mercury, and lead below the limit of quantitation of less than or equal to 0.01%. The test material was stable at ambient temperature. Based on the work described in this manuscript, the test article was suitable for use as a source of zinc in studies of deficiency and excess in the diet.
Figure 1. X-ray diffraction pattern.
X-ray diffraction pattern from (a) zinc carbonate basic test article, (b) zinc carbonate basic test article (gray) and zinc carbonate hydroxide (black), and (c) zinc carbonate basic test article, zinc carbonate hydroxide, and zinc oxide. Peaks where the test article and zinc carbonate hydroxide differ correspond to zinc oxide peaks.
- Figure 1 (59 KB)
Figure 2. Infrared spectra.
Infrared spectra from the (a) zinc carbonate basic test article, (b) zinc carbonate hydroxide, and (c) zinc oxide.
- Figure 2 (50 KB)
Figure 3. TGA weight percentage and rate of weight loss curves.
TGA weight percentage and rate of weight loss curves from the zinc carbonate basic test article. The average weight loss was 23.3%.
- Figure 3 (50 KB)
Figure 4. XRF spectrum.
Figure 4. (a) XRF spectrum for the zinc carbonate basic test article analyzed with cellulose filter. (b) XRF spectrum for zinc carbonate basic test article analyzed with no filter. The large Rh peaks are artifacts of the X-ray source.
- Figure 4 (49 KB)
Figure 5. Equivalent XRD patterns and Equivalent infrared spectra.
(a) Equivalent XRD patterns from multiple aliquots (n = 3) of the zinc carbonate basic test article stored at ambient temperature and stored frozen as a reference (n = 2).
(b) Equivalent infrared spectra from multiple aliquots (n = 3) of the zinc carbonate basic test article stored at ambient temperature and stored frozen as a reference (n = 2).
- Figure 5 (80 KB)
Table 1. Comparison of zinc carbonate basic test article and reference.
Comparison of zinc carbonate basic test article and reference card X-ray diffraction patterns.
- Table 1 (254 KB)
Table 2. Infrared spectra of zinc carbonate basic test article and zinc compounds.
- Table 2 (146 KB)
Table 3. ICP-OES analyses of zinc carbonate basic test article for zinc and selected metals.
- Table 3 (156 KB)