Improved functionalization of electrospun PLLA/gelatin scaffold by alternate soaking method for bone tissue engineering

• Published in: Applied surface science 2013-03, Vol.268, p.477-488
• Main Authors: Jaiswal, Amit K., Kadam, Sachin S., Soni, Vivek P., Bellare, Jayesh R.
• Format: Article
• Language: English
• Subjects: Biomaterials; Biomimetic; Cell proliferation; Complement activation; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electrospinning; Exact sciences and technology; Mineralization; Physics
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.12.152

► Hydroxyapatite (HA) worked as a binder of gelatin in composite scaffold. ► Osteoblasts activity was found to be highest on PLLA/Gel/HA at day 7 compared to all other scaffolds. ► PLLA/Gel and PLLA/Gel/HA exhibited minimum terminal complement complex concentration. ► PLLA/Gel/HA scaffold displayed better osteostimulation with lesser immune response. Biomimetic biomaterials are widely being explored as scaffold for bone regeneration. In this study, we prepared poly-l-lactic acid/hydroxyapatite (PLLA/HA) and poly-l-lactic acid/gelatin/hydroxyapatite (PLLA/Gel/HA) scaffold by electrospinning of poly-l-lactic acid (PLLA) and a blend of poly-l-lactic acid/gelatin (PLLA/Gel) followed by hydroxyapatite (HA) mineralization via alternate soaking in calcium and phosphate (Ca–P) solutions. HA growth on scaffold after each soaking cycle was confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The functional groups (COO and NH2) of gelatin in the PLLA/Gel scaffold facilitated the surface nucleation of HA as compared to the PLLA scaffold. Leaching study showed HA in PLLA/Gel/HA scaffold acts as binder of gelatin and eliminates use of toxic crosslinking agents. In vitro cell attachment on these scaffolds was assessed by using human osteosarcoma cells (MG-63). Cell proliferation on scaffolds was examined by MTT assay. MTT results clearly indicated that mineralized scaffolds did not inhibit the eventual cell proliferation. Alkaline phosphatase (ALP) activity of MG-63 cells was found to be the highest on PLLA/Gel/HA at day 7 compared to all other scaffolds. Complement activation study revealed minimum terminal complement complex (TCC) concentration for PLLA/Gel and PLLA/Gel/HA (617.33 and 654.13ng/mL respectively). These results demonstrate the proficiency of PLLA/Gel/HA scaffold in better osteostimulation with lesser immune response, which attributed to synergistic role of gelatin and HA. Thus, by mimicking the natural microenvironment PLLA/Gel/HA scaffolds can become the choice of material in bone tissue engineering.