Instituto de Química Física de Materiales, Ambiente y Energía (INQUIMAE) Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Pabellón II, C1428EGA, Buenos Aires, Argentina.
Appl Spectrosc. 2013 Aug;67(8):884-91. doi: 10.1366/12-06981.
The interaction of 4-hydroxy-3-methoxybenzaldehyde (vanillin) and Hylon VII due to the formation of an inclusion complex is studied using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and circular dichroism (CD). The results confirm the close interaction among the different functional groups of vanillin and its host. In addition, a second case study was carried out with an amylose from a different source (100% amylose [APT III]). As a result, remarkable differences were found in the vanillin complexation capability of this amylose, which is only shown in solution by circular dichroism spectroscopy studies through a clear Cotton effect. This finding confirms the value of using CD studies, which shows that, depending on the amylose source, inclusion complexes can be found in solution, or both in solution and the coexisting precipitates, as shown using other techniques, such as X-ray diffraction (XRD) or differential scanning calorimetry (DSC). Moreover, solubility assays and complexation of both starches with iodine and subsequent absorption spectroscopy studies gives more information regarding the possible source of the starch encapsulation capability. Thus, Hylon VII shows higher capacity as vanillin encapsulant than APT III, showing the formation of inclusion complexes both in solution and solid phase, whereas APT III complexes are only perceivable in solution.
利用傅里叶变换红外光谱(FT-IR)、差示扫描量热法(DSC)和圆二色性(CD)研究了 4-羟基-3-甲氧基苯甲醛(香草醛)与 Hylon VII 之间因形成包合物而产生的相互作用。结果证实了香草醛及其主体的不同官能团之间的密切相互作用。此外,还对另一种来源的直链淀粉(100%直链淀粉[APT III])进行了第二次案例研究。结果发现,这种直链淀粉的香草醛络合能力存在显著差异,这仅通过圆二色性光谱研究在溶液中通过明显的Cotton 效应显示出来。这一发现证实了使用 CD 研究的价值,表明根据直链淀粉的来源,包合物可以在溶液中找到,也可以在溶液中和共存的沉淀物中找到,这可以通过 X 射线衍射(XRD)或差示扫描量热法(DSC)等其他技术来证明。此外,对两种淀粉与碘的络合及其随后的吸收光谱研究提供了更多关于淀粉包封能力可能来源的信息。因此,Hylon VII 作为香草醛包封剂的能力高于 APT III,在溶液和固相中均形成包合物,而 APT III 复合物仅在溶液中可察觉。