Interaction between polydeoxyadenylic acid and β-glucan from Lentinus edodes

• Published in: European polymer journal 2012-07, Vol.48 (7), p.1329-1338
• Main Authors: Liu, Qingye, Xu, Xiaojuan, Zhang, Lina, Yu, Junping
• Format: Article
• Language: English
• Subjects: Applied sciences; Atomic force microscopy; Dynamics; Exact sciences and technology; Helical; Interaction; Lentinan; Nanocomposites; Nanomaterials; Nanostructure; Natural polymers; Physicochemistry of polymers; Polydeoxyadenylic acid; Spectra; Starch and polysaccharides; β-Glucan
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2012.04.004

[Display omitted] The interaction between polydeoxyadenylic acid (poly(dA)) and single chains of Lentinan (s-LNT) was investigated by circular dichroism spectra (CD), UV–Vis spectra, nano-differential scanning calorimetry (nano-DSC), dynamic light scattering (DLS), and atomic force microscopy (AFM). All the experimental results indicated that poly(dA) really interacted with s-LNT having molecular weight of 5.3×105 to form a novel composite with stiff conformation through hydrogen bonding, whereas the triple helical Lentinan (t-LNT) could not, implying that it was the single chain but not the triple helical chain interacted with poly(dA). Meanwhile, the interaction strongly depended on the concentration of s-LNT and pH. When the poly(dA) concentration was fixed at 5.3μg/ml, the interaction between poly(dA) and s-LNT increased with an increase in s-LNT concentration, then reached the maximum at ∼60μg/ml, finally decreased with further increase of s-LNT concentration. This was due to self-renaturation of s-LNT into triple helix or incomplete species confirmed by nano-DSC. The poly(dA)/s-LNT complex could exist in solutions with pH 5.5–11.5, and pH 7–10 was the optimal condition for the complex, showing higher stability against pH than the positive control of poly(dA)/s-SPG. The dynamic behaviors of the complex demonstrated that the interaction between s-LNT and poly(dA) occurred rapidly, and reached stable within 3–7h. Moreover, the thermal stability of poly(dA) was enhanced by complexation with s-LNT. The topograph of the poly(dA)/s-LNT complex was shown as rod-like stiff architecture. This work enlarges the application of LNT in the biomedical field.