Optimization of a 3D bioprinting process using ultrashort peptide bioinks

Abstract

The field of three-dimensional (3D) bioprinting is rapidly emerging as an additive manufacturing method for tissue and organ fabrication. The demand for tissues and organ transplants is ever increasing, although donors are not as readily available. Consequently, tissue engineering is gaining much attention to alleviate this problem. The process of achieving well-structured 3D bioprinted constructs using hydrogel bioinks depends on symmetrical precision, regulated flow rates, and viability of cells. Even with the mentioned parameters optimized, the printed structures need additional refining by removing excessive liquids, as peptide hydrogel bioprints encapsulate water. However, it is challenging to eliminate the confined fluids without compromising the printing process. In this paper, we introduced a vacuum system to our 3D bioprinting robotic arm and thus optimized the printing quality for complex and refined 3D scaffolds. Moreover, the proposed vacuum system supports printing with cells. Our results show improved printing resolution which facilitates the printing of higher and more stable structures.

Time-dependent pulsing of microfluidic pumps to enhance 3D bioprinting of peptide bioinks

“…Finally, two Cellix® syringe pumps were loaded with the peptide mixture and 5x PBS solution as a buffer to activate the gelation. The optimal flow rate range of both syringe pumps had been determined in previous studies to ensure that the liquid solutions emerge at a reasonable speed in coordination with the printing speed [12] . The optimized flow rates ranged from 55±5 µl/min for the peptide hydrogel and 20±5 µl/min for phosphate-buffered saline solution (PBS).…”

Engineered Microgels—Their Manufacturing and Biomedical Applications

“…Self-assembling peptides have also been used in 3D bioprinting [ 110 ]. Stable 3D scaffolds were fabricated using ultrashort self-assembling peptides in a vacuum system that utilizes a robotic arm [ 108 ].…”

“…The bioprinted 3D structures have proven biocompatible and maintained cell viability post bioprinting. Both microgels and nanoparticles made from ultrashort self-assembling peptides can be used in bioprinting applications, as mentioned before [ 109 , 110 ]. The flexibility of combining different forms of gels made from ultrashort self-assembling peptides, i.e., bulk peptide hydrogels and peptide microgels as well as peptide nanoparticles, renders this class of self-assembling peptides a very attractive platform system for a variety of biomedical applications and for applications in regenerative and personalized medicine.…”

Enhancing Peptide Biomaterials for Biofabrication

“…This has required the development of novel fabrication setups to enhance gelation. Bioprinting techniques amenable to SAP bioinks include droplet printing [ 98 , 99 , 100 , 101 ], or the generation of droplets which are then extruded [ 100 , 101 ], extrusion printing [ 80 , 81 , 102 , 103 , 104 ], and the customisation of extrusion printing setups, such as coaxial nozzles to mix salt solutions [ 80 , 81 ], printing onto salt-covered substrates [ 82 ], or removing excess fluid with a vacuum print-bed [ 105 ]. This demonstrates that the unique properties of SAP materials can be exploited for bioprinting.…”

“…Synthetic peptide materials give rise to complex biomimetic structures with bioactivity, resulting in controlled cell-scaffold interactions [ 96 , 97 ]. Furthermore, recent reports have demonstrated the translation of synthetic SAP biomaterials into bioinks [ 80 , 81 , 82 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 ]. This demonstrates the potential of synthetic SAP design for biofabrication of organs and tissues, and ultimately clinical translation ( Figure 1 ).…”