The objective of this study is to fabricate customized dosage forms using extrusion‐based 3D printing for the sustained delivery of theophylline. The therapeutic paste was prepared by combining various doses of theophylline (0, 75, 100, and 125 mg) with different concentrations of methylcellulose (MC) A4M (8, 10, and 12%). The paste was then 3D printed into semisolid tablets under optimized printing conditions. The rheological properties of printing pastes were related to the 3D printability. Our results indicated that to be 3D printed using the current platform, the storage modulus (G′) of the printing paste should be higher than the loss modulus (G″) during the frequency sweep (0.1–600 rad/s), and the tan δ should fall in the range of 0.25–0.27 at 0.63 rad/s. The printed tablets formulated with 10% MC showed the highest overall quality, considering the aspects of resolution, texture, and shape retention regardless of the dosage. The scanning electron microscopy images indicated that the cross‐linked structure of MC A4M formed the microscale porous microstructure, which has the potential to embed the theophylline, thus delayed the release through the barrier effect. The in vitro dissolution test revealed that the 3D printed tablets exhibited a sustained release during the first 12 hr. The findings in this study will support the development of customized, personalized medicine with improved efficacy.

中文翻译：

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在药物输送系统中通过半固体挤出增材制造开发基于甲基纤维素的缓释剂。

本研究的目的是使用基于挤出的 3D 打印制造定制剂型，以持续输送茶碱。通过将不同剂量的茶碱（0、75、100 和 125 毫克）与不同浓度的甲基纤维素 (MC) A4M（8、10 和 12%）混合来制备治疗性糊剂。然后在优化的打印条件下将糊状物 3D 打印成半固体片剂。印刷浆料的流变特性与 3D 可印刷性有关。我们的结果表明，要使用当前平台进行 3D 打印，打印浆料的储能模量 (G') 应高于频率扫描 (0.1-600 rad/s) 期间的损耗模量 (G")，并且tanδ  _在 0.63 rad/s 时应在 0.25–0.27 的范围内。无论剂量如何，考虑到分辨率、质地和保形性方面，用 10% MC 配制的印刷片剂的整体质量最高。扫描电镜图像表明，MC A4M的交联结构形成了微尺度的多孔微结构，具有包埋茶碱的潜力，从而通过屏障效应延迟释放。体外溶出度测试显示，3D 打印片剂在前 12 小时内呈现持续释放。本研究的结果将支持开发具有更高疗效的定制化、个性化药物。