Department of Physics and Chemistry - Emilio Segrè, University of Palermo, viale delle Scienze, Palermo 90128, Italy.
Department of Biological, Chemical and Pharmaceutical Sciences (STeBiCeF), University of Palermo, viale delle Scienze, Palermo 90128, Italy.
Int J Biol Macromol. 2024 Mar;260(Pt 2):129452. doi: 10.1016/j.ijbiomac.2024.129452. Epub 2024 Jan 14.
Ageing of paper is a complex process of great relevance for application purposes because of its widespread use as support for information storage in books and documents, and as common low-cost and green packaging material, to name a few. A key factor in paper ageing is the oxidation of cellulose, a macromolecule of natural origin that constitutes the main chemical component of paper. Such a complex process results in changes in the cellulose polymeric chains in chemical and structural properties. The scope of this work is to explore the effects of oxidation of cellulose as one of the principal mechanisms of ageing of paper using a fluorescence-based approach. To this aim, fluorescence-lifetime imaging microscopy (FLIM) measurements on pure cellulose samples stained using Carbotrace 680 dye were performed, and data were analyzed by phasor approach. The comparison with results from conventional techniques allowed to map paper microstructure as a function of the sample oxidation degree correlating the fluorescence-lifetime changes to cellulose oxidation. A two-step oxidation kinetics that produced specific modification in paper organization was highlighted indicating that FLIM measurements using Carbotrace 680 dye may provide a simple tool to obtain information on the oxidation process also adding spatial information at sub-micrometric scale.
纸张老化是一个复杂的过程，与应用密切相关，因为它被广泛用作书籍和文件信息存储的支撑物，以及常见的低成本和绿色包装材料等。纸张老化的一个关键因素是纤维素的氧化，纤维素是一种天然来源的高分子，构成纸张的主要化学成分。这个复杂的过程导致纤维素聚合链在化学和结构性质上发生变化。这项工作的目的是探索使用基于荧光的方法，将纤维素氧化作为纸张老化的主要机制之一的影响。为此，对用 Carbotrace 680 染料染色的纯纤维素样品进行了荧光寿命成像显微镜 (FLIM)测量，并通过相子方法对数据进行了分析。与传统技术的结果进行比较，能够根据样品氧化程度绘制纸张微观结构的图谱，将荧光寿命的变化与纤维素氧化相关联。突出显示了两步氧化动力学，该动力学导致纸张组织的特定修饰，表明使用 Carbotrace 680 染料的 FLIM 测量可以提供一种简单的工具来获取有关氧化过程的信息，还可以在亚微米尺度上添加空间信息。
