The bioflavonoid quercetin may prevent magnetoliposomes oxidation, preserving their stability. In this work, the interaction between quercetin and asolectin-based magnetoliposomes was investigated by monitoring the hydration degree, vibrational, rotational and translational mobility parameters of the system as well as its thermodynamic properties. The efficiency of the encapsulation of maghemite magnetic nanoparticles was detected by high resolution-continuum source flame atomic absorption spectrometry (HR-CS FAAS). The magnetic behavior of the system was studied by vibrating sample magnetometry (VSM) technique. The size and surface charge of magnetoliposomes were detected by dynamic light scattering (DLS) and zeta potential (ζ-potential) measurements. The influence of quercetin on the physico-chemical parameters of the magnetoliposomes was evaluated by Fourier transform infrared spectroscopy (FTIR), ³¹P and ¹H nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC) techniques. In vitro antioxidant and antitumoral assays were also performed for the magnetoliposomes. An insertion of quercetin into magnetoliposomes reduced the efficiency of the encapsulation of maghemite nanoparticles by 11%, suggesting a significant interaction between flavonoid and nanoparticles in a specific region of the system. Quercetin discreetly decreased the saturation magnetization of magnetoliposomes, but did not affect the superparamagnetic behavior of the system. ³¹P and ¹H NMR results showed that quercetin did not alter the inverted hexagonal system phase state but decreased lipid polar head mobility. The flavonoid also seems to reorient the choline group above the bilayer phosphate membrane plane, as indicated by ζ-potential system values. FTIR, NMR and DSC responses showed that quercetin disordered the carbonyl and the methylene regions of the magnetoliposomes. Quercetin, as the nanoparticles, seems to be located in the polar head regions of magnetoliposomes, ordering it and diminishing the lipid intermolecular communication in the membrane carbonyl and non-polar regions. The lipid peroxidation of the magnetoliposomes was prevented 8-fold by the presence of quercetin in the system. Also, the flavonoid was responsible for a 45% reduction in the viability of glioma cells. Location and interactions between quercetin and magnetoliposomes components were discussed in order to be correlated with the results of biological activity, contributing to the design of more stable and efficient magnetoliposomes to be applied as contrast and antitumoral agents.

生物类黄酮槲皮素可以防止脂质体氧化，从而保持其稳定性。在这项工作中，通过监测系统的水合度，振动，旋转和平移迁移率参数及其热力学性质，研究了槲皮素与基于促凝素的磁脂质体之间的相互作用。通过高分辨率连续谱源火焰原子吸收光谱法（HR-CS FAAS）检测了磁赤铁矿磁性纳米粒子的封装效率。通过振动样品磁力法（VSM）技术研究了系统的磁性能。磁脂质体的大小和表面电荷通过动态光散射（DLS）和Zeta电位（ζ电位）测量进行检测。³¹ P和¹ H核磁共振（NMR）和差示扫描量热法（DSC）技术。还对磁脂质体进行了体外抗氧化剂和抗肿瘤测定。槲皮素插入磁脂质体中使磁赤铁矿纳米颗粒的封装效率降低了11％，这表明类黄酮和纳米颗粒在系统特定区域之间存在显着的相互作用。槲皮素谨慎地降低了脂质体的饱和磁化强度，但没有影响系统的超顺磁行为。³¹ P和¹1 H NMR结果表明槲皮素不改变倒置的六边形系统相态，但降低了脂质极性头的迁移率。类黄酮似乎还可以将胆碱基团重新定位在双层磷酸酯膜平面上方，如ζ电位系统值所示。FTIR，NMR和DSC响应表明槲皮素使磁脂质体的羰基和亚甲基区域无序。槲皮素作为纳米颗粒，似乎位于磁脂质体的极性头区域，有序排列并减少了膜羰基和非极性区域中的脂质分子间通讯。系统中存在槲皮素可防止磁脂质体的脂质过氧化8倍。同样，类黄酮导致神经胶质瘤细胞活力降低了45％。