Carlesi Serena, Ricci Marilena, Cucci Costanza, La Nasa Jacopo, Lofrumento Cristiana, Picollo Marcello, Becucci Maurizio
Dipartimento di Chimica ''Ugo Schiff,'' Università degli Studi di Firenze, Polo Scientifico e Tecnologico, via della Lastruccia 3, I-50019, Sesto Fiorentino (Firenze), Italy.
Appl Spectrosc. 2015 Jul;69(7):865-76. doi: 10.1366/14-07775. Epub 2015 Jun 1.
This work explores the application of chemometric techniques to the analysis of lipidic paint binders (i.e., drying oils) by means of Raman and near-infrared spectroscopy. These binders have been widely used by artists throughout history, both individually and in mixtures. We prepared various model samples of the pure binders (linseed, poppy seed, and walnut oils) obtained from different manufacturers. These model samples were left to dry and then characterized by Raman and reflectance near-infrared spectroscopy. Multivariate analysis was performed by applying principal component analysis (PCA) on the first derivative of the corresponding Raman spectra (1800-750 cm(-1)), near-infrared spectra (6000-3900 cm(-1)), and their combination to test whether spectral differences could enable samples to be distinguished on the basis of their composition. The vibrational bands we found most useful to discriminate between the different products we studied are the fundamental ν(C=C) stretching and methylenic stretching and bending combination bands. The results of the multivariate analysis demonstrated the potential of chemometric approaches for characterizing and identifying drying oils, and also for gaining a deeper insight into the aging process. Comparison with high-performance liquid chromatography data was conducted to check the PCA results.
这项工作探索了化学计量技术在通过拉曼光谱和近红外光谱分析脂质漆粘合剂（即干性油）中的应用。这些粘合剂在历史上被艺术家广泛使用，既单独使用，也混合使用。我们制备了从不同制造商获得的各种纯粘合剂（亚麻籽油、罂粟籽油和核桃油）的模型样品。将这些模型样品晾干，然后用拉曼光谱和反射近红外光谱进行表征。通过对相应拉曼光谱（1800 - 750 cm(-1)）、近红外光谱（6000 - 3900 cm(-1)）的一阶导数及其组合应用主成分分析（PCA）进行多变量分析，以测试光谱差异是否能够根据样品的成分对其进行区分。我们发现对区分我们研究的不同产品最有用的振动带是基本的ν(C = C)伸缩振动以及亚甲基伸缩和弯曲组合带。多变量分析的结果证明了化学计量方法在表征和识别干性油以及更深入了解老化过程方面的潜力。与高效液相色谱数据进行了比较以检验PCA结果。
