A handheld bioprinter for multi-material printing of complex constructs

Abstract

In situ bioprinting, also known as the process of depositing bioinks at the defect site, has emerged as a promising strategy for the repair and restoration of large tissues. This technology accomplishes these goals through the site-specific delivery of pro-healing structures. However, realising the full potential of this technology requires the ability to print multiple materials for simultaneous or sequential dispensing of a variety of drugs and cells for better tissue biomimicry. In this article, we describe a portable and modular bioprinter that is capable of depositing a variety of bioinks while allowing for precise control over their physicochemical properties. Using stereolithography (SLA) 3D printing, we construct microfluidic printheads with complex fluid circuitries that allow for the deposition of multi-component fibers with sophisticated cross-sectional geometries and material compositions. In addition, the modular design of this platform makes it possible to print a wide variety of bioinks, such as those that can be chemically or photo-crosslinked, as well as nano-composite inks with shear-thinning and self-healing properties. The versatility of this technology for biomedical applications is demonstrated by printing constructs for co-delivery of various drugs or cells at the same time, as well as generating implanted biosensors. Overall, this method not only has a significant potential for site-specific and in situ tissue printing, but it also has the potential to have applications in traditional ex vivo bioprinting for automated and high throughput tissue engineering.

Sheet-based extrusion bioprinting: a new multi-material paradigm providing mid-extrusion micropatterning control for microvascular applications

“…Chaotic printing reaches the higher resolutions found in lightassisted bioprinting modalities without the aforementioned toxicity concerns of UV light and photoinitiator hydrogel components. Chaotic printing has been demonstrated as a viable strategy for inducing cell alignment, providing vacant channels for pre-vascularization and rapid cell expansion in high surface-area-to-volume bioreactor systems [24][25][26][27][28][29][30][31][32][33][34][35][36]. Chaotic printing has also recently been explored for producing radial and axial micropatterns with up to 8 inks at once [37].…”

“…In addition to achieving high resolutions, bioprinting must also incorporate multiple materials and cell types to replicate the highly structured spatial patterning of different cell types found in native, functional tissues [ 25 ]. In microvascular tissues, for example, vessel walls are primarily comprised of ECs surrounded by a basement membrane interspersed with pericytes (PCs) as vessels branch from arterioles into capillaries and post-capillary venules.…”

In Situ Bioprinting: Process, Bioinks, and Applications

“…However, hand-held bioprinters are portable and can be used regardless of the object size. It offers increased surgical flexibility and real-time design modifications as it is brought directly to the subject . It does not need medical imaging and CAD wound modeling, thus reducing the preparation time and cost.…”

“…The gel used for printing gradually degrades naturally and is replaced by newly formed tissues, facilitating area repair. Recently, an economical hand-held bioprinter was designed for enhanced convenience, featuring switches to control the extrusion process, UV light, and battery operation …”

“…The integration of immune cell-laden collagen matrices further adds to its versatility, enabling the observation of interactions between immune cells and tumoroids, as well as simulated immunotherapy treatments . Moreover, the year 2023 witnessed the introduction of a modular hand-held bioprinter combining stereolithography 3D printing and microfluidic technologies . This bioprinter not only boasts affordability and user-friendliness but also allows for precise control of the physical and chemical properties of bioinks .…”