Synthesis and characterization of hybrid gold-coated cereal particles from sorghum bran flour and wheatbran flour

Authors: NORTON, AMIE - Kansas State University; KIM, MIN JUNG - Bayer Corporation; Peiris, Kamaranga; COX, SARAH - Kansas Department Of Agriculture; Tilley, Michael; Smolensky, Dmitriy; Bean, Scott

Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/29/2024
Publication Date: 10/16/2024
Citation: Norton, A., Kim, M., Peiris, K.H., Cox, S., Tilley, M., Smolensky, D., Bean, S.R. 2024. Synthesis and characterization of hybrid gold-coated cereal particles from sorghum bran flour and wheatbran flour. Cereal Chemistry. 102(1):23-33. https://doi.org/10.1002/cche.10840.
DOI: https://doi.org/10.1002/cche.10840

Interpretive Summary: Nanotechnology potential has been demonstrated to produce value-added materials from cereal biopolymers. Conventionally, nanoparticles (NPs) have been prepared using carbon-based materials, inorganic metals such as gold and silver, organic matter, or composite-base materials. Nanoparticles have been utilized in many applications, such as drug delivery, tissue engineering, biological labeling, pigments and dyes, and processing aids. The various applications for NPs have led to rising demand for NPs fabricated from eco-friendly biomolecules. Phenolics are promising candidates for mitigating many diseases, such as cardiovascular and cancer. These features have led phenolics to be used in novel ways, for example, as the building blocks for developing new nanomedicine for cancer treatment. As phenolics are known to be concentrated in bran from cereal grains, using bran to form NPs complexed with metals such as gold could further demonstrate the potential for bran-based NPs. This project describes an approach to synthesize NPs from isolated bran from sorghum and wheat. Bran from two different sorghum lines was selected, one from a tannin-containing sorghum and one from a non-tannin type, for differences in phenolic composition and content, and bran from wheat was used as a control due to comparatively low phenolic content. In addition, NPs made from bran and gold were produced and compared to NPs made without gold added.

Technical Abstract: This study investigated the effect of using different phenolic-containing grain brans on nanoparticle properties. This study successfully synthesized nanoparticles from bran flour isolated from three different sources: sorghum (Sumac and Burgundy) and hard red winter wheat (cv. 1863). The phenolic contents of the three brans were measured as 33.40, 4.98, and 1.59 mg GAE/g, respectively. NPs synthesized from the bran flour had phenolic content measuring 6.41 (sorghum-Sumac bran), 5.31 (sorghum-Burgundy bran), and 1.15'mg GAE/g (wheat bran). Adding gold to the NPs decreased phenolic content in all three cases: 2.50 (sorghum-Sumac bran), 1.80 (sorghum-Burgundy bran), and 0.30 (wheat-bran) mg GAE/g. Thus, the synthesis had an impact on the phenolic content. The sizes of the particles were measured using dynamic light scattering: 159 (sorghum-Sumac), 78 (sorghum-Burgundy), and 117 (wheat) nm, respectively. After gold was added, the sizes of the particles changed to 113 (sorghum-Sumac), 115 (sorghum-Burgundy), and 94 (wheat) nm, respectively. Cereal bran is an eco-friendly source of biopolymers for producing nanoparticles. With its high phenolic content, sorghum bran is ideal for making nanoparticles with various applications. Wheat and sorghum bran is a mill by-product that can be used to synthesize nanoparticles, increasing the value of these agricultural products. A method was established to develop gold nanoparticles from grain bran. These methods can be used to develop value-added products across many different applications.