Mineralogical, Spectroscopic and Microstructural Characterization of Nigerian Bentonite Before and After Aflatoxin Detoxification of Stored Maize

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@article{1722486,
      author = {Ahmadu Umaru, M. Muhammad, S. Yahuza, P. G. Shiaka, B. S. Mienda},
      title = {Mineralogical, Spectroscopic and Microstructural Characterization of Nigerian Bentonite Before and After Aflatoxin Detoxification of Stored Maize},
      journal = {Iconic Research And Engineering Journals},
      year = {2026},
      volume = {10},
      number = {2},
      pages = {2811-2822},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1722486.pdf},
      abstract = {Aflatoxin B₁ (AFB₁) contamination of maize poses a significant food-safety concern in Nigeria, creating a need for effective, affordable and locally available mitigation materials. This study characterized Nigerian bentonite before and after its application to AFB₁-contaminated stored maize using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS). FTIR analysis showed that the principal aluminosilicate framework was retained after treatment, with characteristic Si–O stretching and hydroxyl-related bands remaining evident, although changes occurred in water-associated absorption bands. XRD analysis identified montmorillonite as the dominant clay mineral, with minor quartz and feldspathic phases, and demonstrated persistence of the principal smectitic structure following application. SEM revealed irregular, flaky and aggregated particles, with observable differences in surface texture and aggregation after treatment. EDS confirmed silicon, iron and aluminium as the major elements, with relatively minor variations in elemental proportions between raw and post-treatment bentonite. Overall, the findings demonstrate that the Nigerian bentonite retained its fundamental mineralogical and aluminosilicate structure while undergoing measurable hydration- and surface-related changes following interaction with stored maize. These characteristics provide a favourable physicochemical basis for further investigation of the material as a locally sourced adsorbent for AFB₁ mitigation. However, quantitative adsorption, desorption, kinetic and toxicological studies are required to establish its detoxification efficiency, binding mechanisms and practical safety.},
      keywords = {Bentonite; Aflatoxin B₁; Montmorillonite; FTIR; XRD; SEM–EDS; Stored maize; Clay adsorbent},
      month = {August},
      doi = {https://doi.org/10.64388/IREV10I2-1722486}
  }