Dual Route Amine Functionalized Poly(l-lactic acid)/Mesoporous Bioactive Glass Based 3D Printed Composite Scaffolds:...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Surface modification of bioactive materials improves bone healing.
• Amine modification of mesoporous bioactive glass (MBG) enhances cell adhesion, pH stability, degradation control, and osteogenic potential for bone tissue engineering.

Purpose of the Study:

• To fabricate 3D printed (3DP) composite scaffolds using amine-grafted MBG incorporated into PLA.
• To investigate the effects of surface decoration with branched polyethyleneimine (PEI) on scaffold properties and bone regeneration.

Main Methods:

• Fabrication of 3DP PLA/N-MBG composite scaffolds with varying N-MBG loading (30:70 organic:inorganic).
• Surface modification with branched PEI (MW ~1200).
• Characterization included mechanical testing, simulated body fluid (SBF) tests, in vitro assays (MTT, Live/Dead, ARS, ALP, qRT-PCR), and in vivo studies in Wistar rats (subcutaneous and calvarial defect models).

Main Results:

• Amide bonding between grafted amines and PLA significantly improved mechanical strength by ~144% despite high N-MBG loading.
• Rapid hydroxyapatite formation observed within 1 day in SBF tests.
• In vitro assays confirmed excellent biocompatibility and osteogenic activity.
• PLA/N-MBG/PEI scaffolds showed enhanced osteogenic activity, with highest ALP activity (~9 mU/mL) and significant upregulation of COL1A2, BMP2, and OCN by day 14.
• In vivo studies demonstrated superior bone regeneration efficacy without chronic inflammation.

Conclusions:

• Dual functionalization of 3DP PLA/N-MBG scaffolds with PEI markedly enhances bioactivity, mechanical integrity, and bone healing capacity.
• This strategy offers significant promise for bone tissue engineering applications.
• The developed composite scaffolds promote effective bone regeneration and possess excellent biocompatibility.