Cooperative Calcium Phosphate Deposition on Collagen-Inspired Short Peptide Nanofibers for Application in Bone Tissue Engineering

Abstract

In recent years, immense attention has been devoted over the production of osteoinductive materials. To this direction, collagen has a dominant role in developing hard tissues and plays a crucial role in the biomineralization of these tissues. Here, we demonstrated for the first time the potential of the shortest molecular pentapeptide domain inspired from collagen toward mineralizing hydroxyapatite on peptide fibers to develop bone-filling material. Our simplistic approach adapted the easy and facile route of introducing the metal ions onto the peptide nanofibers, displaying adsorbed glutamate onto the surface. This negatively charged surface further induces the nucleation of the crystalline growth of hydroxyapatite. Interestingly, nucleation and growth of the hydroxyapatite crystals lead to the formation of a self-supporting hydrogel to construct a suitable interface for cellular interactions. Furthermore, microscopic and spectroscopic investigations revealed the crystalline growth of the hydroxyapatite onto peptide fibers. The physical properties were also influenced by this crystalline deposition, as evident from the hierarchical organization leading to hydrogels with enhanced mechanical stiffness and improved thermal stability of the scaffold. Furthermore, the mineralized peptide fibers were highly compatible with osteoblast cells and showed increased cellular biomarkers production, which further reinforced the potential application toward effectively fabricating the grafts for bone tissue engineering.

Designing Cardin-Motif Peptide and Heparin-Based Multicomponent Advanced Bioactive Hydrogel Scaffolds to Control Cellular Behavior

“…2D cell culture study was carried out to measure cellular growth and proliferation on composite hydrogels . The detail study of 2D cell culture was reported earlier in our previous studies. ,, In this study, different time points of 48, 72, and 120 h have been selected to check the biocompatibility of the composite scaffolds toward neuroblastoma cells. Then, the adhered cells on the composite scaffolds were stained by FDA (fluorescein diacetate) and PI (propidium iodide) to evaluate live and dead cells, respectively. , Then cells were observed at 10× magnification through CLSM (Zeiss Confocal Microscope, LSM880, Carl Zeiss).…”

“…Alamar Blue, a specific fluorescence indicating dye, is used to assess cellular proliferation on the composite hydrogel in different time periods. , The detail study is reported in our earlier literatures. ,, Cellular proliferation was carried out at different intervals of 48, 72, and 120 h. In particular, triplicate studies of this experiment were done to get the averaged data which can be represented as mean ± SD.…”

“…49 The detail study of 2D cell culture was reported earlier in our previous studies. 11,18,21 In this study, different time points of 48, 72, and 120 h have been selected to check the biocompatibility of the composite scaffolds toward neuroblastoma cells. Then, the adhered cells on the composite scaffolds were stained by FDA (fluorescein diacetate) and PI (propidium iodide) to evaluate live and dead cells, respectively.…”

“…47,48 The detail study is reported in our earlier literatures. 11,21,48 Cellular proliferation was carried out at different intervals of 48, 72, and 120 h. In particular, triplicate studies of this experiment were done to get the averaged data which can be represented as mean ± SD.…”

“…This intricate engineering of nature has always been a source of inspiration toward designing and fabricating tissue specific biomolecular scaffolds for regenerative medicine and tissue engineering. − These manmade synthetically designed bioinspired scaffolds are expected to meet the architectural, topographical attributes of the native system so as to generate specific biochemical as well as mechanical cues that can regulate cell growth and tissue regeneration by providing necessary communication to the cells. , Although these bioinspired scaffolds offer several advantages, still there exist multiple challenges in their translational potential toward clinical applications that include safety and cost-effectiveness in using them, and the biodegradability and biocompatibility of these designer scaffolds are of equal importance for the fabrication of advanced tissue mimics . In this direction, significant studies showed the increasing interest in self-assembling peptides due to their biological relevance, bifunctionality, and chemical diversity which is coupled with the possibility of easy modification originating from their established protocol for synthesis. − Furthermore, supramolecular self-assembly is an emerging route to fabricate various nanostructures and biomimetic materials for applications in biomedicine. − In this context, peptide-based biomaterials are facing significant challenges to fulfill all the requirements of the cells in terms of creating an ideal cellular microenvironment to provide necessary biophysical and biochemical cues for controlling cellular behavior. For example, scaffolds derived from only peptides may sometimes demonstrate low mechanical stiffness as well as they may suffer from long-term stability as compared to the polymeric scaffolds. , Additionally, these scaffolds designed from the single component of native ECM cannot fulfill the necessary compositional requirements of the ECM, which may interfere with the cell signaling pathways that are associated with the crucial biomechanical cues, etc.…”