# Centrifugal Fiber-Spinning Device Using Two Pairs of Counter-Facing Syringes for Fabricating Composite Micro/Nanofibers and Three-Dimensional Cell Culture

## TL;DR

A new device creates composite micro/nanofiber scaffolds for tissue engineering, supporting cell growth and mimicking natural structures.

## Contribution

A novel fiber-spinning device using counter-facing syringes to produce integrated micro- and nanofibers in a single structure.

## Key findings

- The device creates 3D scaffolds with homogeneously integrated micro- and nanofibers.
- C2C12 myoblasts adhered well, remained viable, and formed multinucleated cells on the scaffolds.
- Fiber diameter was controllable via polymer concentration and nozzle diameter.

## Abstract

Biomimetic scaffolds are required in tissue engineering to provide structural support as well as promote cell adhesion, proliferation, and differentiation. Fibrous scaffolds composed of micro- and nanofibers replicate the architecture of the native extracellular matrix. Electrospinning is widely used for fabricating nanofibers; however, constructing fibrous scaffolds that integrate multiple fiber scales into a single structure is difficult. We addressed this issue by developing a fiber-spinning device using two pairs of counter-facing syringes that simultaneously produce micro- and nanofibers under different processing conditions. Poly(ε-caprolactone) solutions are ejected through needle-type nozzles via centrifugal force, and fiber diameter is controlled by adjusting the polymer concentration and nozzle diameter. We fabricated scaffolds with the proposed device, which exhibited a random three-dimensional fibrous network in which microfibers and nanofibers were homogeneously integrated. C2C12 myoblasts cultured on the composite scaffolds strongly adhered to the fibrous network, remained viable, and extended along the fibers to form multinucleated cells within the structure. The developed system produced composite micro/nanofiber scaffolds with tunable morphology and biocompatibility, providing a platform for fibrous tissue engineering applications.