ABSTRACT The ability to reproducibly produce and effectively collect electrosprayed polymeric microspheres with controlled morphology and size in bulk form is challenging. In this study, microparticles were produced by electrospraying polycaprolactone (PCL) of various molecular weights and solution concentrations in chloroform, and by collecting materials on different substrates. The resultant PCL microparticles were characterized by optical and electron microscopy to investigate the effect of molecular weight, solution concentration, applied voltage, working distance, and flow rate on their morphology and size. The work demonstrates the key role of a moderate molecular weight and/or solution concentration in the formation of spherical PCL particles via an electrospraying process. Increasing the applied voltage was found to produce smaller and more uniform PCL microparticles. There was a relatively low increase in the particle average size with an increase in the working distance and flow rate. Four types of substrates were adopted to collect electrosprayed PCL particles: a glass slide, aluminium foil, liquid bath, and copper wire. Unlike 2D bulk structures collected on the other substrates, a 3D tubular structure of microspheres was formed on the copper wire which could find application in the construction of 3D tumor mimics.

中文翻译：

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电喷雾聚己内酯微球的制备及表征


摘要 以散装形式可重复地生产和有效收集具有受控形态和尺寸的电喷雾聚合物微球的能力具有挑战性。在这项研究中，通过在氯仿中电喷射不同分子量和溶液浓度的聚己内酯（PCL）并收集不同基质上的材料来产生微粒。通过光学和电子显微镜对所得 PCL 微粒进行表征，研究分子量、溶液浓度、施加电压、工作距离和流速对其形态和尺寸的影响。这项工作证明了中等分子量和/或溶液浓度在通过电喷雾过程形成球形 PCL 颗粒中的关键作用。发现增加施加的电压可以产生更小且更均匀的 PCL 微粒。随着工作距离和流速的增加，颗粒平均尺寸的增加相对较低。采用四种类型的基底来收集电喷雾 PCL 颗粒：载玻片、铝箔、液浴和铜线。与收集在其他基底上的 2D 块状结构不同，在铜线上形成微球的 3D 管状结构，可用于构建 3D 肿瘤模拟物。