One area where engineering can significantly impact healthcare is regenerative medicine, which tackles a critical issue: the shortage of donor organs. Nowadays, tissue loss and organ failure predominantly arise from accidents and diseases. Following the advancements in immunologic suppression, organ transplantation surgeries saw initial success in the early 1960s. However, the limited availability of donor organs remains a considerable obstacle.
Selecting the appropriate biomaterial for supporting cell growth and differentiation in implants is vital for their long-term viability. Biocompatible and biodegradable polymer membranes are promising biomaterials that have shown potential in tissue engineering scaffolds.
Fabrication, Innovative Experiments and Characterization
In partnership with Dayeeta Pal, a Materials Engineer at NIT Durgapur, I conducted a comparative analysis of the physico-chemical, morphological, mechanical properties, and cytotoxicity of nanofibers made from polycaprolactone (PCL) and polymethyl methacrylate (PMMA). This research was carried out at the Center of Healthcare Science and Technology at IIEST Shibpur in West Bengal, India. Both PCL and PMMA are being investigated for their benefits in medical devices and scaffolds, especially in dermatology. These materials possess characteristics ideal for tissue engineering, including the ability to replicate the extracellular matrix (ECM) of tissues. Acting as scaffolds, they facilitate cell attachment, proliferation, and differentiation, thus qualifying them for wound healing solutions.
In my study, I utilized electrospinning to create the polymer nanofibers. To assess the scaffolds’ capability to support cell growth, I characterized them through mechanical testing, Fourier Transform Infrared Spectroscopy (FTIR), wettability tests, and scanning electron microscopy (SEM). The MTT assay was employed to evaluate cytotoxicity. I produced scaffolds from 15 wt% solutions of PCL and PMMA, achieving a thickness of approximately 0.02 mm. Human Adult Dermal Fibroblasts were seeded on the scaffolds to assess biocompatibility.
Initially, I determined the Young’s Modulus and Ultimate Tensile Strength of the electrospun fibrous scaffolds using a Universal Testing Machine. The results indicated that PMMA had a higher Young’s Modulus and tensile strength than PCL. Subsequently, I investigated the functional groups present in the fabricated PCL and PMMA using FTIR. This spectroscopic analysis provided insights into the chemical structure and composition, revealing no significant changes in the polymers’ chemical structures post-electrospinning. This finding suggested that the electrospinning process preserved the scaffolds’ structural integrity and functional characteristics, which was encouraging for my experimental objectives. Furthermore, the FTIR findings offered insights into the interactions of the polymers with cells during the biocompatibility tests, showing that certain functional groups might facilitate cell attachment and growth by interacting with proteins in the cell culture medium.
Wettability is another crucial factor to consider. The contact angle measurements of the electrospun scaffolds showed that PCL possesses hydrophobic traits with a high contact angle, while PMMA demonstrated lower hydrophobicity. This distinction in wetting properties explains the variances in cell attachment and viability, as PMMA supported greater cell survival.
SEM serves as an excellent method for assessing the quality of cell adhesion and examining how fiber properties—such as diameter, surface roughness, and porosity—can impact cellular behavior. The samples (with and without cells) were gold sputter-coated and then observed under SEM.
As illustrated in the detailed images of Fig 1, SEM analysis confirmed that both PCL and PMMA nanofibers provided a conducive surface for fibroblast cell attachment, with PMMA exhibiting superior adhesion efficiency compared to PCL.
Finally, I assessed the performance of the scaffolds cultured with fibroblasts, focusing on cell function, proliferation, and cytotoxicity through the MTT assay. The results indicated a higher number of viable cells in the 15 wt% PMMA scaffolds compared to those made from 15 wt% PCL.
Concluding Thoughts
In conclusion, the primary goal and findings of this experiment show that fibroblasts, capable of producing ECM and collagen, can be effectively cultured on polymer nanofibers, rendering them suitable for future therapeutic uses in dermatology, particularly in burn treatment. The films detailed here are well-suited for treating burns as they prevent moisture loss while facilitating fibroblast attachment and proliferation. The electrospun PCL and PMMA scaffolds were assessed for mechanical strength, hydrophobicity, and cytotoxicity, with PMMA emerging as a preferable option for wound healing applications. Nonetheless, further research employing various cell types is necessary to ensure their safety for application.
I view this study on electrospun PCL and PMMA nanofiber membranes as a notable advancement in the quest for developing innovative biomaterials for tissue engineering and wound healing.
Looking Ahead: My Perspective on 3D Bioprinting
As the field of tissue engineering and regenerative medicine progresses, the integration of 3D bioprinting holds significant promise for transforming wound healing and organ regeneration. This technology can create highly customized and complex scaffolds that closely resemble natural tissue architecture in an efficient and sustainable manner.
It is thrilling to envision the possibility of combining polymeric nanofibers like PCL and PMMA with 3D bioprinting techniques. Utilizing electrospun nanofibers as a foundational framework, 3D bioprinting can develop multi-layered functional tissue constructs that foster cellular behaviors, ultimately providing an enriched environment for cell proliferation, migration, and tissue regeneration. Such innovations stand to address critical challenges, including the shortage of donor organs and the persistent issue of chronic wounds as the field continues to evolve.
I firmly believe that the collaboration among material scientists, biologists, and clinicians is crucial for translating these advancements into practical applications in the future. The outlook for regenerative medicine appears quite optimistic, and the combination of electrospun nanofibers and 3D bioprinting may very well lead to new treatments for tissue loss, organ failure, and various chronic conditions.
