Art Conservation Research Center, Department of Chemistry, Carnegie Mellon University, 700 Technology Drive, Pittsburgh, PA 15219, USA.
Analyst. 2010 Sep;135(9):2434-44. doi: 10.1039/c0an00155d. Epub 2010 Jul 29.
Minimally invasive desorption electrospray ionization-mass spectrometry (DESI-MS) and laser ablation electrospray ionization-MS (LAESI-MS) were used to look for soluble cellulose degradation products produced by accelerated aging in unsized cotton paper. Soluble extracts from papers aged 144 to 26,856 hours were first analyzed in solution using traditional electrospray ionization-MS (ESI-MS). Results were compared to those from direct analysis of condensed phase degradation products extracted from the absorbent paper substrate using DESI-MS and LAESI-MS. ESI-MS results showed evidence of oligosaccharide degradation products ranging from cellobiose to cellononaose; using DESI-MS and LAESI-MS, products from cellobiose to cellodecaose and glucose to cellooctaose, respectively, were observed. As degradation proceeded, increased quantities of both low and high molecular weight oligosaccharides were observed. The analytical approaches developed in the control study were applied for the detection of degradation products in two naturally-aged books dating from the 19th century, both made from cotton and linen. Oligosaccharides ranging from glucose to cellopentaose were observed.
采用微创解吸电喷雾电离质谱（DESI-MS）和激光烧蚀电喷雾电离质谱（LAESI-MS）来寻找未上浆棉纸加速老化产生的可溶纤维素降解产物。使用传统的电喷雾电离质谱（ESI-MS）对 144 至 26,856 小时老化的纸张的可溶性提取物进行了初步分析。结果与使用 DESI-MS 和 LAESI-MS 从吸收性纸张基质中提取的冷凝相降解产物的直接分析结果进行了比较。ESI-MS 结果表明存在从纤维二糖到纤维九糖的寡糖降解产物的证据；使用 DESI-MS 和 LAESI-MS，分别观察到从纤维二糖到纤维十糖和从葡萄糖到纤维八糖的产物。随着降解的进行，观察到低分子量和高分子量寡糖的数量都增加了。在对照研究中开发的分析方法用于检测来自 19 世纪的两本自然老化书籍的降解产物，这两本书均由棉和亚麻制成。观察到从葡萄糖到纤维五糖的寡糖。
