# Biomimetic Porous Inorganic Materials for Bone Engineering Using a Natural Yam Stalk Template

## TL;DR

This study uses yam stalks to create porous inorganic materials that mimic bone structure for tissue engineering, offering sustainable and functional alternatives.

## Contribution

The novel use of yam stalks as a biotemplate to fabricate biomimetic bone scaffolds with interconnected pores and osteogenic potential.

## Key findings

- Silica and titania scaffolds with interconnected macropores were successfully created using yam stalks as a template.
- The scaffolds showed high porosity and a honeycomb-like structure, suitable for cell proliferation and nutrient transport.
- In vitro tests demonstrated good cell viability and osteogenic activity, indicating potential for bone tissue engineering.

## Abstract

This study explores biomimicry as a widely recognized
and promising
approach for developing sustainable structural materials that embody
the principles of the circular economy. In this context, the study
explores using yam stalks (Dioscorea) as a biotemplate.
This natural material, composed of biopolymers such as cellulose and
lignin and typically discarded as tuber waste, is characterized by
a highly porous morphology with a large volume of interconnected pores.
Such a structure can be used as a template to create a bone-mimicking
scaffold with potential applications in tissue engineering. Through
the sol–gel process and the combination of the Dioscorea biotemplate with tetraethyl orthosilicate (TEOS) or titanium bis­(ammonium
lactate) dihydroxide (TiBALDH) precursors, silica and titania inorganic
porous materials were obtained. After sol–gel deposition of
inorganic oxides and removal of the Dioscorea biotemplate
by calcination at 700 °C, scanning electron microscopy (SEM)
revealed a scaffold with a homogeneous network of interconnected macropores
evenly distributed throughout the material. At higher magnification,
hexagonal patterns (honeycomb-like structures) were observed, highlighting
the natural structural optimization that offers advantages in permeability
and cellular growth. Micro CT analysis revealed total volumes of 768.61
mm3 for the silica-based porous scaffold and 853.00 mm3 for the titania-based sample, along with macropores of 203–395
and 176–286 μm per gram, respectively. This pore range
is particularly suitable for cell proliferation and nutrient transport
in applications like tissue engineering. Moreover, in vitro cytotoxicity
and osteogenic assays showed that SD/Ti and SD/Si demonstrated promising
osteogenic potential, with good cell viability, ALP activity, and
collagen production in both culture media. This pore range is particularly
suitable for cell proliferation and nutrient transport in applications
like Tissue Engineering. Therefore, this is a promising scaffold alternative,
suggesting the use of porous biomimetic materials in tissue engineering,
especially synthetic bone. Furthermore, these materials offer multifunctional
applications, are environmentally friendly, and are economically viable.