Electrospining Machine: Synergistic effects of 3D printing and electrospinning technology in bone scaffold fabrication

Background

Bone, as a load-bearing tissue, is the second most commonly transplanted tissue, with more than 2 million bone grafts performed annually. Minor fractures and injuries can be repaired by its regenerative capacity, whereas significant defects require a complete regenerative process. Although autografts and allografts have been used clinically for bone reconstruction for a long time, each has its limitations. Donor site complications and side effects associated with autografts result in long waiting times and at least 20 deaths per day.

The main point of this paper

Advantages of flexible sensors:

Compatible with movable parts or curved surfaces to detect physiological and environmental indicators in real time.

Flexible Sensor Design:

Combines rigid conductive inorganic materials with soft substrates that are stretchable.

Properties of an Ideal Flexible Sensor:

Excellent flexibility, stretchability, and sensitivity to detect a wide range of strains and discriminate human motion.

Importance of micro/nanostructures:

Special structures such as microcracks, serpentine structures, etc., modulate sensor performance.

Nanofiber-based smart sensors:

Same sensing and wearable properties as regular textiles.

Nanofiber Manufacturing Technologies:

Thermal stretching techniques, template synthesis, hydrothermal and electrospinning.

Advantages of electrospinning technology:

Versatile, easy to operate, adjustable and suitable for mass production.

Combining electrospinning and 3D printing: advancing personalized scaffold manufacturing in bone tissue engineering

The importance of tissue engineering:

Tissue engineering combines multidisciplinary experts with the aim of creating functional replacements for damaged tissue by combining engineering principles with life science principles.

Challenges of bone tissue engineering:

Challenges of bone tissue engineering include the repair and functional reconstruction of large bone defects, especially when there is a shortage of donor bone

Selection of scaffold materials:

Commonly used materials for manufacturing customized scaffolds for hard tissues include biopolymers, bioceramics, and composites, which have important roles in cell viability and function.

Combination of natural and synthetic polymers:

The combination of natural and synthetic polymers, which can integrate the characteristics and eliminate the limitations of both, is expected to be a candidate material for BTE clinical applications.

Advantages of electrospinning technology:

Electrospinning technology shows great potential for large-scale industrial production due to its versatility, ease of operation, and flexibility to adjust to produce continuous and specific nanofibers

Combined electrospinning/3D printing technology:

Studies have shown that the combination of electrospinning and 3D printing technologies can effectively promote bone regeneration and prepare scaffolds with hierarchical structures with appropriate features

Summarize

Scaffolds serve as artificial three-dimensional structures designed to support cell growth, adhesion, migration, proliferation and differentiation. Cell behavior includes cell-cell interactions, while cell-biomaterial interactions depend on the designed scaffold properties. Robotic casting, an extrusion-based automated molding technique, has been used as an efficient method of scaffold fabrication, capable of producing complex external geometries as well as controlled internal structures with microstructures and pores. In addition, ES is a continuous process capable of depositing neatly or randomly arranged micro/nanofibers on the substrate surface, providing ideal morphology for cell attachment, growth and differentiation, and enhancing the mechanical properties of the prepared scaffolds.

It has been shown that combining these two techniques can both capitalize on the advantages and compensate for the shortcomings of both approaches. However, the selection of appropriate materials based on the desired biological and engineering properties is crucial for printing or electrospinning applications. Scaffolds prepared through this hybrid approach are expected to be ideal bone substitutes for TE applications.