Abd El-Gawad Walaa M, Abdo Sayeda M
Polymers and Pigments Department, National Research Centre, Dokki, Giza, Egypt.
Water Pollution Research Department, National Research Centre, Dokki, Giza, Egypt.
Sci Rep. 2025 May 2;15(1):15429. doi: 10.1038/s41598-025-97752-3.
This work aims to synthesize economical and eco-friendly naturally sourced nano-pigments with bright colors, antimicrobial activity, and thermal stability from algal cells cultivated in wastewater, which are then harvested, dried, and converted into algal biomass (AB). Algal biomass (AB) was covered by a very thin nano-layer of either zinc ferrite or cerium ferrite, which does not exceed 10%. After the synthesis and characterization, these nanopigments were incorporated into alkyd resin in two proportions (2.5% and 5%). The antimicrobial activity and color of the produced coatings were investigated using the disc diffusion and CIELab methods, respectively. Besides, their thermal stability was examined using scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). The results of antimicrobial activity demonstrate that the effect of all coatings on fungi is greater than their effect on bacteria and that films containing 5% of nano-pigments gave an inhibition zone for microbes greater than those containing 2.5%. Additionally, the thermal stability results of the film containing algal biomass show very high weight loss, reaching 47.5% in group I and 76% in group II. While coatings containing zinc ferrite/AB and cerium ferrite/AB, weight loss doesn't exceed 20%, and films containing 5% are the best.
这项工作旨在从在废水中培养的藻类细胞中合成经济且环保的天然纳米颜料，这些颜料具有鲜艳的颜色、抗菌活性和热稳定性，然后将藻类细胞收获、干燥并转化为藻类生物质（AB）。藻类生物质（AB）被一层不超过10%的非常薄的铁酸锌或铁酸铈纳米层覆盖。在合成和表征之后，这些纳米颜料以两种比例（2.5%和5%）掺入醇酸树脂中。分别使用纸片扩散法和CIELab法研究了所制备涂层的抗菌活性和颜色。此外，使用扫描电子显微镜（SEM）和热重分析（TGA）检查了它们的热稳定性。抗菌活性结果表明，所有涂层对真菌的作用大于对细菌的作用，并且含有5%纳米颜料的薄膜对微生物的抑制圈大于含有2.5%纳米颜料的薄膜。此外，含有藻类生物质的薄膜的热稳定性结果显示出非常高的重量损失，在第一组中达到47.5%，在第二组中达到76%。而含有铁酸锌/AB和铁酸铈/AB的涂层，重量损失不超过20%，含有5%纳米颜料的薄膜是最好的。
