3D Bioplotter Research Papers

Excellent electrical performance of assemblies of 1D silver nanowires (AgNWs) has been demonstrated in the past years. Up to now, however, there are limited approaches to realize simultaneously deterministic assembly with dense arrangement of AgNWs and desired functional layouts. Herein, an assembly strategy from compressed air-modulated alignment of AgNWs to heterogeneous integration of stretchable sensing devices through printing transfer is proposed. In this process, a convective flow induced by compressed air brings the AgNWs to the air–droplet interface, where the AgNWs are assembled with excellent alignment and packing due to the surface flow, van der Waals, and capillary interactions. Compared…

Controlled release of drugs from medical implants is an effective approach to reducing foreign body reactions and infections. We report here on a one-step 3D printing strategy to create drug-eluting polymer devices with a drug-loaded bulk and a drug-free coating. The spontaneously formed drug-free coating dramatically reduces the surface roughness of the implantable devices and serves as a protective layer to suppress the burst release of drugs. A high viscosity liquid silicone that can be extruded based on its shear-thinning property and quickly vulcanize upon exposure to ambient moisture is used as the ink for 3D printing. S-Nitrosothiol type nitric…

Emulsion gels have a wide range of applications. We report on a facile and versatile method to produce stable emulsion gels with tunable rheological properties. Gel formation is triggered by subjecting a mixture containing aqueous colloidal particle (CP) suspensions and water-immiscible liquids to intense turbulence, generated by low frequency (20 kHz) ultrasound or high-pressure homogenization. Through systematic investigations, requisite gel formation criteria are established with respect to both formulation and processing, including ratio/type of liquid pairs, CP properties, and turbulence conditions. Based on the emulsion microstructure and rheological properties, inter-droplet bridging and CP void-filling are proposed as universal stabilization mechanisms.…

The potential translation of bio-inert polymer scaffolds as bone substitutes is limited by the lack of neovascularization upon implantation and subsequently diminished ingrowth of host bone, most likely resulted from the inability to replicate appropriate endogenous crosstalk between cells. Human umbilical vein endothelial cell-derived decellularized extracellular matrix (HdECM), which contains a collection of angiocrine biomolecules, has recently been demonstrated to mediate endothelial cells(ECs) – osteoprogenitors(OPs) crosstalk. We employed the HdECM to create a PCL (polycaprolactone)/fibrin/HdECM (PFE) hybrid scaffold. We hypothesized PFE scaffold could reconstitute a bio-instructive microenvironment that reintroduces the crosstalk, resulting in vascularized bone regeneration. Following implantation in a…

The main aim of this paper is to achieve the suitable SA-GEL (sodium alginate and gelatin) porous cartilage scaffold by 3D printing technology with optimal prediction parameters. Firstly, the characteristics of SA-GEL were analyzed, the influence of calcium chloride on the gel was explored, and the optimal cross-linking concentration and gelation temperature were determined. Secondly, a prediction model of the extrusion line width of SA-GEL was established, in which the printing pressure, the moving speed of the needle and the fiber interval were the important parameters affecting the printing performance of the SA-GEL composite material. Thirdly, the SA-GEL composite scaffolds…

This study investigates if the application of bone marrow-derived mesenchymal stem cells (BM-MSCs) loaded 3D-printed scaffolds could improve rotator cuff repair. The polylactic-co-glycolic acid (PLGA) scaffolds were fabricated by 3D print technology. Rabbit BM-MSCs were transfected with a recombinant adenovirus encoding bone morphogenic protein 12 (BMP-12). The effect of BM-MSCs loaded PLGA scaffolds on tendon-bone healing was assessed by biomechanical testing and histological analysis in a rabbit rotator cuff repair model. We found that the PLGA scaffolds had good biocompatible and biodegradable property. Overexpression of BMP-12 increased the mRNA and protein expression of tenogenic genes in BM-MSCs cultured with DMEM…

Vascularization is a fundamental prerequisite for large bone construct development and remains one of the main challenges of bone tissue engineering. Our current study presents the combination of 3D printing technique with a hydrogel-based prevascularization strategy to generate prevascularized bone constructs. Human adipose derived mesenchymal stem cells (ADMSC) and human umbilical vein endothelial cells (HUVEC) were encapsulated within our bioactive hydrogels, and the effects of culture conditions on in vitro vascularization were determined. We further generated composite constructs by forming 3D printed polycaprolactone/hydroxyapatite scaffolds coated with cell-laden hydrogels and determined how the co-culture affected vascularization and osteogenesis. It was demonstrated…