Compositional and in Vitro Evaluation of Nonwoven Type I Collagen/Poly-dl-lactic Acid Scaffolds for Bone Regeneration

Abstract

Poly-dl-lactic acid (PDLLA) was blended with type I collagen to attempt to overcome the instantaneous gelation of electrospun collagen scaffolds in biological environments. Scaffolds based on blends of type I collagen and PDLLA were investigated for material stability in cell culture conditions (37 °C; 5% CO2) in which post-electrospinning glutaraldehyde crosslinking was also applied. The resulting wet-stable webs were cultured with bone marrow stromal cells (HBMSC) for five weeks. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), Fourier transform infra-red spectroscopy (FTIR) and biochemical assays were used to characterise the scaffolds and the consequent cell-scaffold constructs. To investigate any electrospinning-induced denaturation of collagen, identical PDLLA/collagen and PDLLA/gelatine blends were electrospun and their potential to promote osteogenic differentiation investigated. PDLLA/collagen blends with w/w ratios of 40/60, 60/40 and 80/20 resulted in satisfactory wet stabilities in a humid environment, although chemical crosslinking was essential to ensure long term material cell culture. Scaffolds of PDLLA/collagen at a 60:40 weight ratio provided the greatest stability over a five-week culture period. The PDLLA/collagen scaffolds promoted greater cell proliferation and osteogenic differentiation compared to HMBSCs seeded on the corresponding PDLLA/gelatine scaffolds, suggesting that any electrospinning-induced collagen denaturation did not affect material biofunctionality within 5 weeks in vitro.

Plasma surface functionalization of biodegradable electrospun scaffolds for tissue engineering applications

“…Therefore, PDLLA has been used in drug delivery systems or in the rare TE applications requiring low strength scaffolds [43]. As a consequence, PDLLA nanofibers were rarely electrospun for TE purposes, unless the polymer is blended with other biodegradable polymers [53][54][55].…”

Development of Bionanocomposites Based on PLA, Collagen and AgNPs and Characterization of Their Stability and In Vitro Biocompatibility

“…Due to their good biocompatibility, the PLA-based materials were extensively used in the field of tissue engineering. However, in order to obtain better optimized scaffolds and to increase cell proliferation and cell adhesion on their surface, PLA have been mixed with other polymers, such as collagen, gelatin or graphene oxide [44,45]. For instance, Qiao et al [45] found that PLA/collagen electrospun fibrous scaffolds at a 60:40 weight ratio showed greatest stability, cell attachment, cell proliferation, and osteogenic differentiation of bone marrow stromal cells after five-week culture period.…”

Polylactic Acid Based Nanocomposites: Promising Safe and Biodegradable Materials in Biomedical Field

“…It has facilitated numerous humans due to the long-term dedication to the structure, function, and growth mechanism of biological tissues against the background of cellular biology and bioengineering development. Scaffolds, as the carriers of cell adhesion and growth, play a decisive role in tissue engineering and have been used in many branches, such as bone regeneration [69], blood vessel [70], and neural system [71]. Ideal scaffolds should not only have suitable construction beneficial to cells growing but also have excellent biofunctionality because the behavior of cells can be easily influenced by the local environment, including some biochemical and mechanical cues [72].…”

“…Many other biomaterials such as collagen and graphene oxide are gradually introduced to polymerize with PLA or PLGA in order to obtain optimized scaffold structures. Qiao et al [69] blended type I collagen with PDLLA and finally found that when type I collagen occupied a proportion of 40% in the scaffolds, PDLLA/collagen scaffolds showed greatest stability, cell proliferation, and osteogenic differentiation after five-week cultivation. As is shown in Figures 3(a) Shin et al [72] successfully fabricated hybrid fiber matrices GO-PLGA-Col composed of PLGA and collagen (Col) impregnated with GO via an electrospinning technique.…”

“…Electrospinning process was well utilized in the researches mentioned above [69,71,72] and electrospinning is indeed an effective way to prepare scaffolds due to its numerous superiorities such as mass production capability and high surface areas of scaffolds. However, there are many other methods including solvent casting/particulate leaching [73], phase separation [74], emulsion freeze-drying [75], gas formation [76], and fiber bonding [77].…”