微纳电子技术

微流控芯片技术在疾病模型、药物筛选和个性化医疗领域显示出巨大的应用潜力。针对传统二维微流控芯片在模拟复杂生物环境方面存在局限性的问题，开发了一种新型的适用于挤出式3D打印的高分子共混材料，该混合材料由聚L-丙交酯-己内酯(PLCL)和聚乙二醇(PEG)组成。测试了PLCL和PEG质量比分别为7∶3、6∶4、5∶5的三种混合材料的流变性能，筛选最佳配比材料，优化打印工艺参数，实现了复杂三维结构的高精度打印，并且打印件具备明显的抗塌陷能力和飞线断丝的可控性。提出了一种创新的微流控芯片分区设计与打印方法，将芯片结构分为4个区域并单独优化打印轨迹，有效减少了悬空结构产生的塌陷。实验结果显示，PLCL和PEG质量比为7∶3的混合材料具有良好的可打印性能，在3 mm/s的打印速度、20 mm/s的飞线速度下，成功实现了无需溶芯材料的三维微流控芯片的打印，微通道截面显示了良好的形状。细胞实验显示，PLCL/PEG材料支架对人脐静脉内皮细胞(HUVEC)具有良好的细胞相容性，并且具有调节巨噬细胞极化、促进M2型表型形成的能力，显示了其在抗炎和免疫调节方面的功能。研究结果为微流控芯片的制造提供了新的材料和制备技术，拓展了3D打印在生物医学领域的应用范围，并为未来器官芯片技术的临床转化提供了实验基础。

Microfluidic chip technology has demonstrated significant application potential in disease modeling, drug screening, and personalized medicine. However, traditional 2D microfluidic chips have limitations in simulating complex biological environments. To address the issue, a novel polymer blends suitable for extrusion 3D printing was developed, which composed of polyl-lactide-caprolactone(PLCL) and polyethylene glycol(PEG). The rheological properties of three blend materials with mass ratios of PLCL and PEG of 7∶3, 6∶4, and 5∶5 were examined, and the optimal matching materials were selected, while the printing process parameters were optimized to achieve the high-precision printing of complex three-dimensional structures. It also possesses remarkable anti-collapse ability and controllability of filament breakage. An innovative microfluidic chip partition design and printing method were proposed, dividing the chip structure into four regions with individually optimized printing trajectories, effectively reducing collapses in suspended structures. The experimental results indicate that the blend material with a PLCL/PEG mass ratio of 7∶3 exhibits excellent printable performance, and the 3D microfluidic chip without core material is successfully printed with high precision at a printing speed of 3 mm/s and a filament travel speed of 20 mm/s, and the cross-section of the microchannel presents a favorable shape. Cell experiments reveal that the PLCL/PEG scaffold displays good cytocompatibility with human umbilical vein endothelial cells(HUVECs), and is capable of regulating the polarization of macrophages and promoting the formation of the M2-type phenotype, signifying its anti-inflammatory and immunomodulatory functions. The research results provides new materials and manufacturing techniques for microfluidic chip fabrication, expanding the applications of 3D printing in the biomedical field and laying an experimental foundation for the clinical translation of organ-on-a-chip technology in the future.