Universidad de Alcalá, Facultad de Ciencias, Departamento de Química Analítica, Química Física e Ingeniería Química, Ctra. Madrid-Barcelona Km. 33.6, 28805 Alcalá de Henares, Madrid, Spain.
Universidad de Alcalá, Facultad de Ciencias, Departamento de Química Analítica, Química Física e Ingeniería Química, Ctra. Madrid-Barcelona Km. 33.6, 28805 Alcalá de Henares, Madrid, Spain; Universidad de Alcalá, Instituto de Investigación Química Andrés M. del Río (IQAR), Ctra. Madrid-Barcelona Km. 33.6, 28805 Alcalá de Henares, Madrid, Spain.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Oct 5;278:121302. doi: 10.1016/j.saa.2022.121302. Epub 2022 Apr 28.
Graphene oxide (GO) is acquiring a great interest in biomedicine, biotechnology and biochemistry due to its unique properties. However, GO layers are boundbyvan der Waals forces, which results in aggregation. An efficient dispersion of the aggregated nanostructures is crucial from an application viewpoint, hence eco-friendly procedures are pursued. In this work, the potential of tannic acid (TA) as a GO dispersant in water has been investigated for the first time. Transmission electronic microscopy (TEM) was used to visualize the degree of GO exfoliation in the dispersions. To further assess TA dispersant capability, a fluorescent biomolecule, riboflavin, has been selected. GO and TA cause a quenching effect on riboflavin fluorescence, which depends on the GO and TA concentration, the GO/TA weight ratio and the final centrifugation step that was found to be crucial. Multiple regression analysis has been used to determine the quenching constants for TA and GO simultaneously. The GO-riboflavin interaction weakens upon centrifugation. This step, traditionally used to remove the nanomaterial aggregates, should be avoided to obtain a high GO concentration in the dispersions. This study paves the way towards the use of environmentally friendly dispersant agents instead of conventional organic solvents or synthetic surfactants to attain high-quality dispersions of carbon nanomaterials in water.
氧化石墨烯（GO）由于其独特的性质，在生物医学、生物技术和生物化学领域引起了极大的兴趣。然而，GO 层之间通过范德华力结合，导致其聚集。从应用的角度来看，高效分散聚集的纳米结构至关重要，因此人们正在寻求环保的方法。在这项工作中，首次研究了单宁酸（TA）作为 GO 在水中的分散剂的潜力。透射电子显微镜（TEM）用于观察分散体中 GO 剥离的程度。为了进一步评估 TA 分散剂的能力，选择了一种荧光生物分子——核黄素。GO 和 TA 对核黄素荧光有猝灭作用，这取决于 GO 和 TA 的浓度、GO/TA 的重量比以及最终的离心步骤，发现后者至关重要。多元回归分析被用于同时确定 TA 和 GO 的猝灭常数。GO-核黄素相互作用在离心后减弱。通常，这个步骤用于去除纳米材料的聚集物，但为了在分散体中获得高浓度的 GO，应该避免这个步骤。这项研究为使用环保的分散剂代替传统的有机溶剂或合成表面活性剂来获得高质量的碳纳米材料在水中的分散体铺平了道路。
