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RESEARCH ARTICLE

CNT-Type Dependent Cellular Adhesion on 3D-Printed

Nanocomposite for Tissue Engineering

Adam A. Mieloch *, Julia A. Semba , Jakub D. Rybka *
1
1,2
1
1 Center for Advanced Technology, Adam Mickiewicz University, Poznan, Poland
2 Faculty of Biology, Adam Mickiewicz University, Poznan, Poland

Abstract: At present, one of the main limitations of three-dimensional (3D) bioprinting in tissue engineering stems from a
scarcity of biomaterials tailored for specific applications. Widely used hydrogels offer an optimal printability and a suitable
environment for cell growth; however, they lack the mechanical strength required for non-soft tissues, for example, cartilage,
tendons, and meniscus. This work investigated the physicochemical, mechanical, and biological characteristics of a 3D-printed
polycaprolactone (PCL) reinforced with multiwalled carbon nanotubes (MWCNT) and “bamboo-like” carbon nanotubes
(BCNT) with the following w/w % concentrations: 0.005%, 0.01%, 0.02%, and 0.2%. The materials were analyzed with
subsequent techniques: Scanning electron microscopy, nanoindentation, parallel plate rheometry, and differential scanning
calorimetry. Biological evaluations were performed with normal human articular chondrocytes by confocal microscopy and
proliferation assay. The study revealed that the carbon nanotubes (CNT) addition improved the rheological properties of
the material by increasing the setting temperature. Moderate enhancement was observed in terms of mechanical properties.
The most significant difference was noted in cell adhesion and proliferation. Pure PCL did not facilitate cell growth and
mainly apoptotic cells were observed on its surface. The addition of 0.01% MWCNT resulted in enhanced adhesion and
proliferation; however, the morphology of the cells remained spherical, signifying a suboptimal surface for proliferation.
Interestingly, PCL reinforced with 0.02% BCNT displayed excellent facilitation of cellular adhesion and proliferation, which
is uncharacteristic of pure PCL. In summary, this study investigated the potential of CNT-reinforced PCL for 3D bioprinting
and tissue engineering, highlighting key physicochemical, mechanical, and biological aspects of this biomaterial.

Keywords: 3D bioprinting; Polycaprolactone; Carbon nanotubes; Tissue engineering nanocomposite

*Correspondence to: Jakub D. Rybka, Center for Advanced Technology, Adam Mickiewicz University, Poznan, Poland; jrybka@amu.edu.pl;
Adam A. Mieloch, Center for Advanced Technology, Adam Mickiewicz University, Poznan, Poland; amieloch@amu.edu.pl

Received: December 7, 2021; Accepted: January 15, 2022; Published Online: March 29, 2022
Citation: Mieloch AA, Semba JA, Rybka JD, 2022, CNT-Type Dependent Cellular Adhesion on 3D-Printed Nanocomposite
for Tissue Engineering. Int J Bioprint, 8(2):548. http://doi.org/10.18063/ijb.v8i2.548

1. Introduction are an excellent additive candidate, supplementing
both inadequacies of the PCL. Structurally, CNT can
Polycaprolactone (PCL) is a semicrystalline biodegradable be viewed as sheets of graphene rolled into cylinders.
polyester with a melting temperature of ~60°C. It is There are several morphologically distinct forms of
FDA-approved for use in surgical implants and drug CNT, resulting in varying physicochemical properties.
delivery devices and is widely studied for applications in Nonetheless, CNT are one of the strongest materials in
tissue engineering and regenerative medicine . Due to nature with Young’s modulus on the order of 270 – 950
[1]
its low melting temperature and proven biocompatibility, GPa and tensile strength of 11 – 63 GPa . In terms of
[6]
it is the most commonly used thermoplastic polymer for biocompatibility, they have been extensively studied for
three-dimensional (3D) bioprinting [2-5] . However, its tailored biomaterial engineering of tissues such as cardiac
mechanical and bioadhesive properties are suboptimal tissue, neural tissue, bone, and cartilage [7-10] . In addition,
for non-soft tissue engineering and can be improved on a significant body of work regarding CNT-reinforced
by implementing additives. Carbon nanotubes (CNT) nanocomposites and their characteristics can be found in

© 2022 Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution License, permitting distribution and
reproduction in any medium, provided the original work is properly cited.
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