The inkjet technique has the capability of generating droplets in the picoliter volume range, firing thousands of times in a few seconds and printing in the noncontact manner. Since its emergence, inkjet technology has been widely utilized in the publishing industry for printing of text and pictures. As the technology developed, its applications have been expanded from two-dimensional (2D) to three-dimensional (3D) and even used to fabricate components of electronic devices. At the end of the twentieth century, researchers were aware of the potential value of this technology in life sciences and tissue engineering because its picoliter-level printing unit is suitable for depositing biological components. Currently inkjet technology has been becoming a practical tool in modern medicine serving for drug development, scaffold building, and cell depositing. In this article, we first review the history, principles and different methods of developing this technology. Next, we focus on the recent achievements of inkjet printing in the biological field. Inkjet bioprinting of generic biomaterials, biomacromolecules, DNAs, and cells and their major applications are introduced in order of increasing complexity. The current limitations/challenges and corresponding solutions of this technology are also discussed. A new concept, biopixels, is put forward with a combination of the key characteristics of inkjet printing and basic biological units to bring a comprehensive view on inkjet-based bioprinting. Finally, a roadmap of the entire 3D bioprinting is depicted at the end of this review article, clearly demonstrating the past, present, and future of 3D bioprinting and our current progress in this field.

中文翻译：

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生物材料的喷墨生物打印。

喷墨技术能够在皮升体积范围内产生液滴，在几秒钟内喷射数千次并以非接触方式打印。喷墨技术自出现以来，就被广泛应用于出版行业，用于文字和图片的印刷。随着技术的发展，其应用已从二维（2D）扩展到三维（3D），甚至用于制造电子设备的组件。二十世纪末，研究人员意识到这项技术在生命科学和组织工程中的潜在价值，因为其皮升级打印单元适用于沉积生物成分。目前喷墨技术已成为现代医学中的实用工具，用于药物开发、支架建设、和细胞沉积。在本文中，我们首先回顾了开发这项技术的历史、原理和不同的方法。接下来，我们重点介绍喷墨打印在生物领域的最新成果。通用生物材料、生物大分子、DNA 和细胞的喷墨生物打印及其主要应用按复杂性递增的顺序介绍。还讨论了该技术当前的限制/挑战和相应的解决方案。结合喷墨打印的关键特性和基本生物单元，提出了一个新概念，即生物像素，为基于喷墨的生物打印带来了全面的视角。最后，在这篇评论文章的末尾描绘了整个 3D 生物打印的路线图，清楚地展示了过去、现在、