Here, we propose a novel and simple method to efficiently capture the diffusion of fluorescein isothiocyanate (FITC)-dextran from a biocompatible substance and load the drug only to the tip of DNA microneedles. A dispensing and suction method was chosen to fabricate the designed microneedles with efficient amounts of FITC as the drug model. Importantly, the vacuum process, which could influence the capturing of FITC diffusion from the tip, was evaluated during the manufacturing process. In addition, the simulations were consistent with the experimental results and showed apparent diffusion. Moreover, dextrans of different molecular weights labeled with FITC were chosen to fabricate the tip of microneedles for demonstrating their applicability. Finally, a micro-jetting system with a micro-nozzle (diameter: 80 μm) was developed to achieve the accurate and rapid loading of small amounts of FITC using the anti-diffusion and micro-jetting methods. Our method not only uses a simple and fast manufacturing process, but also fabricates the tips of microneedles more efficiently with FITC compared with the existing methods. We believe that the proposed method is essential for the clinical applications of the microneedle drug delivery platform.

中文翻译：

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仅将药物装载到DNA微针尖端的有效分配方法

在这里，我们提出了一种新颖而简单的方法，可以有效捕获生物相容性物质中的异硫氰酸荧光素（FITC）-葡聚糖的扩散，并将药物仅加载到DNA微针的尖端。选择一种分配和抽吸方法，以有效量的FITC作为药物模型来制造设计的微针。重要的是，在制造过程中评估了可能影响从尖端捕获FITC扩散的真空过程。此外，模拟结果与实验结果一致，并显示出明显的扩散。此外，选择了用FITC标记的不同分子量的右旋糖酐来制造微针头，以证明其适用性。最后，是带有微喷嘴（直径：开发80μm）以使用反扩散和微喷射方法实现少量FITC的准确快速加载。我们的方法不仅使用简单且快速的制造过程，而且与现有方法相比，使用FITC可以更有效地制造微针头。我们认为，所提出的方法对于微针给药平台的临床应用至关重要。