PolySciTech (www.polyscitech.com) provides a wide
array of PLGA polymer components. Recently PolyVivo AP030 (PLGA 85:15,
Mn-10,000-15,000) was utilized to generate porous PLGA/CaSiO3 composite
scaffolds which were tested for their potential applications in use for bone
scaffolding. Read more: Qi, Lin.
"Porous PLGA-CaSiO3 (Pseudowollastonite) Composite Scaffolds Optimized for
Biocompatibility and Osteoinduction." PhD diss., University of Akron,
2014. Full-Text available: https://etd.ohiolink.edu/!etd.send_file?accession=akron1397041385&disposition=inline
“ABSTRACT: The goal of this study
was to develop an optimal porous composite scaffold, composed of
pseudowollastonite (psw; β-CaSiO3), and poly(L,D-lactic-co-glycolic acid)
(PLGA). In culture medium, the psw released Ca2+ and soluble silica, which are
osteoinductive soluble factors. PLGA was utilized as a structural framework and
to maintain pH of the scaffold. Scaffolds were prepared by solvent casting/particle
leaching technique to obtain porosity and interconnectivity of pores. The mass
of NaCl, psw and PLGA were adjusted to determine the effects of the different
components on the scaffold’s biocompatibility and osteoinductive potential, in
vitro, on two types of cells, hMSC (human Mesenchymal Stem Cells) and MC3T3
(murine osteoblast precursor cells). An orthogonal study was designed for 9
scaffold compositions. Scanning electron microscopy and micro-computed
tomography showed that the scaffold pore structure depended on the amount of
NaCl used during fabrication. Variable porosity, and hydrolysis of the psw and
PLGA components resulted in pH changes and different released soluble silica
concentrations. Total DNA analysis from cell culture in growth medium showed
that scaffold compositions which resulted in a small pH shift (± 0.5 on Day 3)
and low soluble silica concentration (65±3 ppm) were less cytotoxic than
scaffolds for which pH changes were large (±1.2 on Day 3) and soluble silica
concentrations were high (87±5 ppm). The viability of hMSCs was lower than that
of MC3T3 under the same set of conditions. The hMSCs were incubated on each
scaffold surface for 28 days in osteogenic induction medium and alkaline
phosphatase staining was used as a preliminary estimate of osteoinductivity of
scaffolds. Two scaffold compositions, which showed lower cytotoxicity and
higher osteoinductivity than the other compositions, were selected for
LIVE/DEAD® staining. Better cell morphology and attachment was observed for the
scaffold composed of low NaCl, intermediate psw and intermediate PLGA contents,
compared to the scaffold of intermediate NaCl, intermediate psw and high PLGA
content. Thus, the optimum psw-PLGA scaffold composition was determined for
cell attachment, viability and a preliminary estimate of osteoinduction.”
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