The fabrication of microfluidic devices through fused deposition modeling (FDM) 3D printing has faced several challenges, mainly regarding obtaining microchannels with suitable transparency and sizes. Thus, the use of this printing system to fabricate microdevices for analytical and bioanalytical applications is commonly limited when compared to other printing technologies. However, for the first time, this work shows a systematic study to improve the potential of FDM 3D printers for the fabrication of transparent microfluidic devices. Several parameters and printing characteristics were addressed in both theoretical and experimental ways. It was found that the geometry of the printer nozzle plays a significant role in the thermal radiation effect that limits the 3D printing resolution. This drawback was minimized by adapting an airbrush tip (0.2 mm orifice diameter) to a conventional printer nozzle. The influence of the height and width of the extruded layer on the resolution and transparency in 3D-printed microfluidic devices was also addressed. Following the adjustments proposed, microchannels were obtained with an average width of around 70 μm ± 11 μm and approximately 80% visible light transmission (for 640 μm thickness). Therefore, the reproducibility and resolution of FDM 3D printing could be improved, and this achievement can expand the capability of this printing technology for the development of microfluidic devices, particularly for analytical applications.

中文翻译：

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了解和改进 FDM 3D 打印以制造高分辨率和光学透明的微流体设备

通过熔融沉积建模 (FDM) 3D 打印制造微流体装置面临着几个挑战，主要是关于获得具有合适透明度和尺寸的微通道。因此，与其他打印技术相比，使用这种打印系统来制造用于分析和生物分析应用的微型设备通常受到限制。然而，这项工作首次展示了一项系统研究，以提高 FDM 3D 打印机制造透明微流体设备的潜力。以理论和实验方式解决了几个参数和印刷特性。结果表明，打印机喷嘴的几何形状在限制 3D 打印分辨率的热辐射效应中起着重要作用。通过调整喷枪尖端 (0. 2 毫米孔口直径）到传统打印机喷嘴。还解决了挤压层的高度和宽度对 3D 打印微流体设备的分辨率和透明度的影响。根据提议的调整，获得了平均宽度约为 70 μm ± 11 μm 和大约 80% 可见光透射率（640 μm 厚度）的微通道。因此，FDM 3D 打印的再现性和分辨率可以得到提高，这一成果可以扩展这种打印技术在微流体设备开发中的能力，特别是在分析应用中。根据提议的调整，获得了平均宽度约为 70 μm ± 11 μm 和大约 80% 可见光透射率（640 μm 厚度）的微通道。因此，FDM 3D 打印的再现性和分辨率可以得到提高，这一成果可以扩展这种打印技术在微流体设备开发中的能力，特别是在分析应用中。根据提议的调整，获得了平均宽度约为 70 μm ± 11 μm 和大约 80% 可见光透射率（640 μm 厚度）的微通道。因此，FDM 3D 打印的再现性和分辨率可以得到提高，这一成果可以扩展这种打印技术在微流体设备开发中的能力，特别是在分析应用中。