Department of Chemistry and Biochemistry, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79968, USA; University of California Centre for Environmental Implications of Nanotechnology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79968, USA.
Environmental Science and Engineering PhD Program, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79968, USA; University of California Centre for Environmental Implications of Nanotechnology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79968, USA.
Sci Total Environ. 2021 Jun 20;774:145699. doi: 10.1016/j.scitotenv.2021.145699. Epub 2021 Feb 6.
Rutile titanium dioxide nanoparticles (nTiO) were weathered in field soil at 0, 100, 200, and 400 mg Ti/kg soil for four months. Two types of nTiO with different surface coatings (hydrophilic and hydrophobic), uncoated nTiO (pristine), and the untreated control were included. Thereafter, carrot seeds (Daucus carota L.) were sown in those soils and grown in a growth chamber for 115 days until full maturity. A comparison was made between this and our previous unaged study, where carrots were treated in the same way in soil with freshly amended nTiO. The responses of plants depended on the nTiO surface coating and concentration. The aged hydrophobic and hydrophilic-coated nTiO induced more positive effects on plant development at 400 and 100 mg Ti/kg soil, respectively, compared with control and pristine treatments. Taproot and leaf fresh biomass and plant height were improved by up to 64%, 40%, and 40% compared with control, respectively. Meanwhile, nutrient elements such as Fe in leaves, Mg in taproots, and Ca, Zn, and K in roots were enhanced by up to 66%, 64%, 41, 143% and 46%, respectively. However, the contents of sugar, starch, and some other metal elements in taproots were negatively affected, which may compromise their nutritional quality. Taken together, the overall growth of carrots was benefited by the aged nTiO depending on coating and concentration. The aging process served as a potential sustainable strategy to alleviate the phytotoxicity of unweathered nanoparticles.
锐钛矿型二氧化钛纳米颗粒（nTiO）在田间土壤中经过 0、100、200 和 400mgTi/kg 土壤的风化处理，历时四个月。本研究包含了两种具有不同表面涂层（亲水和疏水）的 nTiO、未涂层的 nTiO（原始）以及未经处理的对照。此后，将胡萝卜种子（Daucus carota L.）播种到这些土壤中，并在生长室中生长 115 天，直到完全成熟。本研究将其与我们之前未老化的研究进行了比较，即在相同的土壤中用新鲜添加的 nTiO 处理胡萝卜。植物的反应取决于 nTiO 的表面涂层和浓度。与对照和原始处理相比，老化的疏水和亲水涂层 nTiO 分别在 400 和 100mgTi/kg 土壤下对植物发育产生了更积极的影响。主根和叶片的鲜重生物量和株高分别提高了 64%、40%和 40%。同时，叶片中的 Fe、主根中的 Mg 以及根中的 Ca、Zn 和 K 等营养元素分别提高了 66%、64%、41%、143%和 46%。然而，主根中的糖、淀粉和一些其他金属元素的含量受到负面影响，这可能会降低其营养价值。总的来说，取决于涂层和浓度，老化的 nTiO 对胡萝卜的整体生长是有益的。老化过程是一种潜在的可持续策略，可以减轻未风化纳米颗粒的植物毒性。
