Doxorubicin (DOX) is a common drug in cancer chemotherapy, and its high DNA-binding affinity can be harnessed in preparing DOX-loaded DNA nanostructures for targeted delivery and therapeutics. Although DOX has been widely studied, the existing literature of DOX-loaded DNA-carriers remains limited and incoherent. Here, based on an in-depth spectroscopic analysis, we characterize and optimize the DOX loading into different 2D and 3D scaffolded DNA origami nanostructures (DONs). In our experimental conditions, all DONs show similar DOX binding capacities (one DOX molecule per two to three base pairs), and the binding equilibrium is reached within seconds, remarkably faster than previously acknowledged. To characterize drug release profiles, DON degradation and DOX release from the complexes upon DNase I digestion was studied. For the employed DONs, the relative doses (DOX molecules released per unit time) may vary by two orders of magnitude depending on the DON superstructure. In addition, we identify DOX aggregation mechanisms and spectral changes linked to pH, magnesium, and DOX concentration. These features have been largely ignored in experimenting with DNA nanostructures, but are probably the major sources of the incoherence of the experimental results so far. Therefore, we believe this work can act as a guide to tailoring the release profiles and developing better drug delivery systems based on DNA-carriers.

中文翻译：

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阐明阿霉素和DNA折纸纳米结构之间的相互作用，以实现可定制的化疗药物释放

阿霉素（DOX）是癌症化疗中的常用药物，可以利用其高的DNA结合亲和力来制备载有DOX的DNA纳米结构，用于靶向递送和治疗。尽管已经对DOX进行了广泛研究，但现有的DOX负载DNA载体文献仍然有限且不连贯。在这里，基于深入的光谱分析，我们表征和优化将DOX装载到不同的2D和3D支架式DNA折纸纳米结构（DONs）中。在我们的实验条件下，所有DON都显示出相似的DOX结合能力（每两到三个碱基对一个DOX分子），并且结合平衡在几秒钟内就达到了，比以前公认的要快得多。为了表征药物释放曲线，研究了DNase I消化后复合物中的DON降解和DOX释放。对于受雇的DON，取决于DON的超结构，相对剂量（每单位时间释放的DOX分子）可能相差两个数量级。此外，我们确定了DOX聚集机制和与pH，镁和DOX浓度相关的光谱变化。这些特征在用DNA纳米结构进行实验中被很大程度上忽略了，但是到目前为止，可能是导致实验结果不一致的主要原因。因此，我们认为这项工作可以作为调整释放曲线和开发基于DNA载体的更好药物递送系统的指南。这些特征在用DNA纳米结构进行实验中被很大程度上忽略了，但是到目前为止，可能是导致实验结果不一致的主要原因。因此，我们相信这项工作可以作为调整释放曲线和开发基于DNA载体的更好药物递送系统的指南。这些特征在用DNA纳米结构进行实验中被很大程度上忽略了，但是到目前为止，可能是导致实验结果不一致的主要原因。因此，我们认为这项工作可以作为调整释放曲线和开发基于DNA载体的更好药物递送系统的指南。