Highlighting the Importance of Surface Grafting in
Combination with a Layer-by-Layer Approach for Fabricating Advanced
3D Poly(l‑lactide) Microsphere Scaffolds
posted on 2016-04-28, 00:00authored byRobertus
Wahyu N. Nugroho, Karin Odelius, Anders Höglund, Ann-Christine Albertsson
A combined
surface treatment (i.e., surface grafting and a layer-by-layer
(LbL) approach) is presented to create advanced biomaterials, i.e.,
3D poly(l-lactide) (PLLA) microsphere scaffolds, at room
temperature. The grafted surface plays a crucial role in assembling
polyelectrolyte multilayers (PEMs) onto the surface of the microspheres,
thus improving the physicochemical properties of the 3D microsphere
scaffolds. The grafted surface of the PLLA microspheres demonstrates
much better PEM adsorption, improved surface coverage at low pH, and
smoother surfaces at high pH compared with those of nongrafted surfaces
of PLLA microspheres during the assembly of PEMs. They induce more
swelling than nongrafted surfaces after the assembly of the PEMs and
exhibit blue emission after functionalization of the microsphere surface
with a fluorescent dye molecule. The 3D scaffolds functionalized with
and without nanosheets not only exhibit good mechanical performance
similar to the compressive modulus of cancellous bone but also exhibit
the porosity required for cancellous bone regeneration. The magnetic
nanoparticle-functionalized 3D scaffolds result in an electrical conductivity
in the high range of semiconducting materials (i.e., 1–250
S cm–1). Thus, these 3D microsphere scaffolds fabricated
by surface grafting and the LbL approach are promising candidates
for bone tissue engineering.