Stimuli-responsive behaviors and controlled release in liposomes are pivotal in nanomedicine. To this end, we present an approach using a photoresponsive azobenzene nanocluster (AzDmpNC), prepared from azobenzene compounds through melting and aggregation. When integrated with liposomes, they form photoresponsive vesicles. The morphology and association with liposomes were investigated by using transmission electron microscopy. Liposomes loaded with calcein exhibited a 9.58% increased release after UV exposure. To gain insights into the underlying processes and elucidate the mechanisms involved. The molecular dynamic simulations based on the reactive force field and all-atom force field were employed to analyze the aggregation of isomers into nanoclusters and their impacts on phospholipid membranes, respectively. The results indicate that the nanoclusters primarily aggregate through π–π and T-stacking forces. The force density inside the cis-isomer of AzDmpNC formed after photoisomerization is lower, leading to its easier dispersion, rapid diffusion, and penetration into the membrane, disrupting the densification.

中文翻译：

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光响应偶氮苯纳米簇修饰脂质体：实验与模拟相结合的机理分析

脂质体的刺激响应行为和控释在纳米医学中至关重要。为此，我们提出了一种使用光响应偶氮苯纳米簇（AzDmpNC）的方法，该纳米簇由偶氮苯化合物通过熔化和聚集制备而成。当与脂质体结合时，它们形成光响应囊泡。通过使用透射电子显微镜研究形态和与脂质体的关联。负载钙黄绿素的脂质体在紫外线照射后释放量增加了 9.58%。深入了解底层过程并阐明所涉及的机制。基于反作用力场和全原子力场的分子动力学模拟分别分析了异构体聚集成纳米团簇及其对磷脂膜的影响。结果表明，纳米团簇主要通过 π-π 和 T 堆积力聚集。光异构化后形成的AzDmpNC顺式异构体内部的力密度较低，导致其更容易分散、快速扩散和渗透到膜中，破坏致密化。