A review on 3D printing in tissue engineering applications

In tissue engineering, 3D printing is an important tool that uses biocompatible materials, cells, and supporting components to fabricate complex 3D printed constructs. This review focuses on the cytocompatibility characteristics of 3D printed constructs, made from different synthetic and natural materials. From the overview of this article, inkjet and extrusion-based 3D printing are widely used methods for fabricating 3D printed scaffolds for tissue engineering. This review highlights that scaffold prepared by both inkjet and extrusion-based 3D printing techniques showed significant impact on cell adherence, proliferation, and differentiation as evidenced by in vitro and in vivo studies. 3D printed constructs with growth factors (FGF-2, TGF-β1, or FGF-2/TGF-β1) enhance extracellular matrix (ECM), collagen I content, and high glycosaminoglycan (GAG) content for cell growth and bone formation. Similarly, the utilization of 3D printing in other tissue engineering applications cannot be belittled. In conclusion, it would be interesting to combine different 3D printing techniques to fabricate future 3D printed constructs for several tissue engineering applications.

Multifaceted Characterization And In Vitro Assessment Of Polyurethane-Based Electrospun Fibrous Composite For Bone Tissue Engineering

Introduction

Recently several new approaches were emerging in bone tissue engineering to develop a substitute for remodelling the damaged tissue. In order to resemble the native extracellular matrix (ECM) of the human tissue, the bone scaffolds must possess necessary requirements like large surface area, interconnected pores and sufficient mechanical strength.

Materials and methods

A novel bone scaffold has been developed using polyurethane (PE) added with wintergreen (WG) and titanium dioxide (TiO₂). The developed nanocomposites were characterized through field emission scanning electron microscopy (FESEM), Fourier transform and infrared spectroscopy (FTIR), X-ray diffraction (XRD), contact angle measurement, thermogravimetric analysis (TGA), atomic force microscopy (AFM) and tensile testing. Furthermore, anticoagulant assays, cell viability analysis and calcium deposition were used to investigate the biological properties of the prepared hybrid nanocomposites.

Results

FESEM depicted the reduced fibre diameter for the electrospun PE/WG and PE/WG/TiO2 than the pristine PE. The addition of WG and TiO₂ resulted in the alteration in peak intensity of PE as revealed in the FTIR. Wettability measurements showed the PE/WG showed decreased wettability and the PE/WG/TiO₂ exhibited improved wettability than the pristine PE. TGA measurements showed the improved thermal behaviour for the PE with the addition of WG and TiO₂. Surface analysis indicated that the composite has a smoother surface rather than the pristine PE. Further, the incorporation of WG and TiO₂ improved the anticoagulant nature of the pristine PE. In vitro cytotoxicity assay has been performed using fibroblast cells which revealed that the electrospun composites showed good cell attachment and proliferation after 5 days. Moreover, the bone apatite formation study revealed the enhanced deposition of calcium content in the fabricated composites than the pristine PE.

Conclusion

Fabricated nanocomposites rendered improved physico-chemical properties, biocompatibility and calcium deposition which are conducive for bone tissue engineering.

Enhanced mechanical, thermal and biocompatible nature of dual component electrospun nanocomposite for bone tissue engineering

Traditionally, in the Asian continent, oils are a widely accepted choice for alleviating bone-related disorders. The design of scaffolds resembling the extracellular matrix (ECM) is of great significance in bone tissue engineering. In this study, a multicomponent polyurethane (PU), canola oil (CO) and neem oil (NO) scaffold was developed using the electrospinning technique. The fabricated nanofibers were subjected to various physicochemical and biological testing to validate its suitability for bone tissue engineering. Morphological analysis of the multicomponent scaffold showed a reduction in fiber diameter (PU/CO-853 ± 141.27 nm and PU/CO/NO-633 ± 137.54 nm) compared to PU (890 ± 116.911 nm). The existence of CO and NO in PU matrix was confirmed by an infrared spectrum (IR) with the formation of hydrogen bond. PU/CO displayed a mean contact angle of 108.7° ± 0.58 while the PU/CO/NO exhibited hydrophilic nature with an angle of 62.33° ± 2.52. The developed multicomponent also exhibited higher thermal stability and increased mechanical strength compared to the pristine PU. Atomic force microscopy (AFM) analysis depicted lower surface roughness for the nanocomposites (PU/CO-389 nm and PU/CO/NO-323 nm) than the pristine PU (576 nm). Blood compatibility investigation displayed the anticoagulant nature of the composites. Cytocompatibility studies revealed the non-toxic nature of the developed composites with human fibroblast cells (HDF) cells. The newly developed porous PU nanocomposite scaffold comprising CO and NO may serve as a potential candidate for bone tissue engineering.

Electrospun Combination of Peppermint Oil and Copper Sulphate with Conducive Physico-Chemical properties for Wound Dressing Applications

The ultimate goal in tissue engineering is to fabricate a scaffold which could mimic the native tissue structure. In this work, the physicochemical and biocompatibility properties of electrospun composites based on polyurethane (PU) with added pepper mint (PM) oil and copper sulphate (CuSO₄) were investigated. Field Emission Electron microscope (FESEM) study depicted the increase in mean fiber diameter for PU/PM and decrease in fiber diameter for PU/PM/CuSO₄ compared to the pristine PU. Fourier transform infrared spectroscopy (FTIR) analysis revealed the formation of a hydrogen bond for the fabricated composites as identified by an alteration in PU peak intensity. Contact angle analysis presented the hydrophobic nature of pristine PU and PU/PM while the PU/PM/CuSO₄ showed hydrophilic behavior. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness for the PU/PM while PU/PM/CuSO₄ showed a decrease in surface roughness compared to the pristine PU. Blood compatibility studies showed improved blood clotting time and less toxic behavior for the developed composites than the pristine PU. Finally, the cell viability of the fabricated composite was higher than the pristine PU as indicated in the MTS assay. Hence, the fabricated wound dressing composite based on PU with added PM and CuSO₄ rendered a better physicochemical and biocompatible nature, making it suitable for wound healing applications.

Blood compatibility assessments of novel electrospun PVA/egg white nanocomposite membrane

In this study, a novel electrospun wound dressing based on polyvinyl alcohol (PVA) incorporated with egg white was fabricated. The fabricated scaffold was characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR) and contact angle measurement. Further, the coagulation assays were used to investigate the blood compatibility of the developed nanocomposites. The prepared PVA/egg white nanofibers exhibited reduced fiber and pore diameter in comparison to pristine PVA. The FTIR spectrum revealed the interaction between the PVA and egg white by the formation of the new characteristic peaks. Further, the wettability of the prepared nanocomposites was found to be increased with the mean contact angle of 54 ± 1·62°, indicating enhanced hydrophilic nature compared to pristine PVA (62 ± 1·19°). The coagulation assay results revealed that the prepared PVA/egg white nanocomposites showed delayed blood clotting, indicating better blood compatibility. Moreover, the hemolytic index of prepared PVA/egg white nanocomposites (0·94%) was observed to be low compared to pristine PVA (1·5%), suggesting its enhanced safety to red blood cells. Hence, the electrospun PVA/egg white nanocomposites exhibited better physicochemical properties and enhanced blood compatibility properties, which might serve as a valuable candidate for chronic wound healing applications.

Engineering electrospun multicomponent polyurethane scaffolding platform comprising grapeseed oil and honey/propolis for bone tissue regeneration

Essential oils play an important role in reducing the pain and inflammation caused by bone fracture.In this study, a scaffold was electrospun based on polyurethane (PU), grape seed oil, honey and propolis for bone tissue-engineering applications. The fiber diameter of the electrospun PU/grape seed oil scaffold and PU/grape seed oil/honey/propolis scaffold were observed to be reduced compared to the pristine PU control. FTIR analysis revealed the existence of grape seed oil, honey and propolis in PU identified by CH band peak shift and also hydrogen bond formation. The contact angle of PU/grape seed oil scaffold was found to increase owing to hydrophobic nature and the contact angle for the PU/grape seed/honey oil/propolis scaffold were decreased because of hydrophilic nature. Further, the prepared PU/grape seed oil and PU/grape seed oil/honey/propolis scaffold showed enhanced thermal stability and reduction in surface roughness than the control as revealed in thermogravimetric analysis (TGA) and atomic force microscopy (AFM) analysis. Further, the developed nanocomposite scaffold displayed delayed blood clotting time than the pristine PU in the activated prothrombin time (APTT) and partial thromboplastin time (PT) assay. The hemolytic assay and cytocompatibility studies revealed that the electrospun PU/grape seed oil and PU/grape seed oil/honey/propolis scaffold possess non-toxic behaviour to red blood cells (RBC) and human fibroblast cells (HDF) cells indicating better blood compatibility and cell viability rates. Hence, the newly developed electrospun nanofibrous composite scaffold with desirable characteristics might be used as an alternative candidate for bone tissue engineering applications.

Single-stage electrospun innovative combination of polyurethane and neem oil: Synthesis, characterization and appraisal of blood compatibility

Wound healing is a complex process and it requires proper scaffolding for regeneration. An ideal scaffold should provide optimal environmental conditions in order to assist cellular attachment, proliferation and differentiation. In this work, a new composite based on polyurethane and neem oil was fabricated using one-step electrospinning technique. Fabricated composite patch along with the pristine polyurethane was characterized through scanning electron microscopy, Fourier transform and infrared spectroscopy, thermogravimetric analysis, contact angle measurement and atomic force microscopy. Moreover, the blood compatibility was evaluated using activated partial thromboplastin time, partial thromboplastin time and haemolysis assay. Scanning electron microscopy studies of composites revealed the existence of fibres with a smaller diameter (635  ± 105 nm) compared to the pristine polyurethane (969 ± 217 nm). Fourier transform and infrared analysis revealed the formation of hydrogen bond and peak shifting characteristics confirming the interaction of the neem oil with the polyurethane. Contact angle analysis showed the decrease in contact angle indicating the hydrophilic nature of the fabricated patch compared to pristine polyurethane. Thermal gravimetric analysis depicted the better thermal stability of the novel composite patch due to the existence of neem oil in the pristine polyurethane. The presence of neem oil in polyurethane matrix also resulted in an increase in the surface roughness as observed in the AFM analysis. The novel composite patch showed an ability to reduce the thrombogenicity and promoting the anticoagulant nature signified by blood compatibility assays like activated partial thromboplastin time and partial thromboplastin time. Finally, the haemolytic percentage of the fabricated composite (1%) was found to be reduced compared to control (2.733%) indicating better blood compatibility and safety with the red blood cells. Following the results, the fabricated patches offered enhanced physicochemical and blood compatible nature making it as a promising candidate for wound healing application.

Electrospun polyurethane nanofibrous composite impregnated with metallic copper for wound-healing application

In this study, a wound dressing based on polyurethane (PU) blended with copper sulphate nanofibers was developed using an electrospinning technique. The prepared PU and PU nanocomposites showed smooth fibers without any bead defects. The prepared nanocomposites showed smaller fiber (663 ± 156.30 nm) and pore (888 ± 70.93 nm) diameter compared to the pristine PU (fiber diameter 1159 ± 147.48 nm and pore diameter 1087 ± 62.51 nm). The interaction of PU with copper sulphate was evident in the infrared spectrum through hydrogen-bond formation. Thermal analysis displayed enhanced weight residue at higher temperature suggesting interaction of PU with copper sulphate. The contact angle measurements revealed the hydrophilic nature of the prepared nanocomposites (71° ± 2.309°) compared with pure PU (100° ± 0.5774°). The addition of copper sulphate into the PU matrix increased the surface roughness, as revealed in the atomic force microscopy (AFM) analysis. Mechanical testing demonstrated the enhanced tensile strength behavior of the fabricated nanocomposites (18.58 MPa) compared with the pristine PU (7.12 MPa). The coagulation assays indicated the enhanced blood compatibility of the developed nanocomposites [activated partial thromboplastin time (APTT)-179 ± 3.606 s and partial thromboplastin time (PT)-105 ± 2.646 s] by showing a prolonged blood clotting time compared with the pristine PU (APTT-147.7 ± 3.512 s and PT-84.67 ± 2.517 s). Furthermore, the hemolysis and cytotoxicity studies suggested a less toxicity nature of prepared nanocomposites by displaying low hemolytic index and enhanced cell viability rates compared with the PU membrane. It was observed that the fabricated novel wound dressing possesses better physicochemical and enhanced blood compatibility properties, and may be utilized for wound-healing applications.

Cancer-related fatigue treatment: An overview

Cancer-related fatigue is a symptom of cancer where most patients or the general practitioners tend to misinterpret due to the insufficient understanding or knowledge of cancer-related fatigue (CRF). This paper will provide a better perspective for the patients and the health professionals on how to manage and handle CRF for both mild and severe fatigue patients. Articles were selected from the searches of PubMed database that had the terms "randomized controlled trials," "cancer," "fatigue," "pharmacologic treatment," and "nonpharmacologic treatment" using both Mesh terms and keywords. The authors have reviewed the current hypothesis and evidence of the detailed etiology of the CRF present in the literature for healthier management, directives, and strategies to improve the treatment of cancer-related fatigue. An algorithm has been blueprinted on screening, and management, of the CRF, and various kinds of effective treatments and assessment tools have been briefly studied and explained. Although many strategies seemed promising, the quality of randomized controlled trials is generally quite low in studies, making it difficult to draw conclusions about the effectiveness of each self-care strategies. Therefore, future studies require better design and reporting of methodological issues to ensure evidence-based self-care recommendations for people receiving cancer treatment.

Preparation, characterization and blood compatibility assessment of a novel electrospun nanocomposite comprising polyurethane and ayurvedic-indhulekha oil for tissue engineering applications

Electrospun polyurethane based nanocomposite scaffolds were fabricated by mixing with indhulekha oil. Scanning electron microscope (SEM) portrayed the nanofibrous nature of the composite and the average diameters of the composite scaffold were smaller than the pristine scaffolds. The fabricated scaffold was found to be hydrophobic (114°) due to the inclusion of indhulekha oil, which was displayed in contact angle measurement analysis. The fourier transform infrared spectroscopy (FTIR) results indicated that the indhulekha oil was dispersed in PU matrix identified by formation of hydrogen bond and peak shifting of CH group. The PU/indhulekha oil nanocomposite exhibits a higher decomposition onset temperature and also residual weight percentage at 900°C was more compared to the pure PU. Surface roughness was found to be increased in the composite compared to the pristine PU as indicated by the atomic force microscopy (AFM) analysis. In order to investigate the blood compatibility of electrospun nanocomposites the activated partial thromboplastin time (APTT) assay, prothrombin time (PT) assay and hemolytic assay were performed. The blood compatibility results APTT and PT revealed that the developed nanocomposites demonstrated delayed clotting time indicating the anticoagulant nature of the composite in comparison with the pristine PU. Further, it was also observed that the hemolytic index of nanocomposites was reduced compared to pure PU suggesting the non-hemolytic nature of the fabricated scaffold. Hence, the fabricated nanocomposites might be considered as a potent substitute for scaffolding damaged tissue due to their inherent physicochemical and blood compatibility properties.

Development and blood compatibility assessment of electrospun polyvinyl alcohol blended with metallocene polyethylene and plectranthus amboinicus (PVA/mPE/PA) for bone tissue engineering

Introduction

Currently, the design of extracellular matrix (ECM) with nanoscale properties in bone tissue engineering is challenging. For bone tissue engineering, the ECM must have certain properties such as being nontoxic, highly porous, and should not cause foreign body reactions.

Materials and methods

In this study, the hybrid scaffold based on polyvinyl alcohol (PVA) blended with metallocene polyethylene (mPE) and plectranthus amboinicus (PA) was fabricated for bone tissue engineering via electrospinning. The fabricated hybrid nanocomposites were characterized by scanning electron microscopy (SEM), Fourier transform and infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), contact angle measurement, and atomic force microscopy (AFM). Furthermore, activated partial thromboplastin time (APTT), prothrombin time (PT), and hemolytic assays were used to investigate the blood compatibility of the prepared hybrid nanocomposites.

Results

The prepared hybrid nanocomposites showed reduced fiber diameter (238±45 nm) and also increased porosity (87%) with decreased pore diameter (340±86 nm) compared with pure PVA. The interactions between PVA, mPE, and PA were identified by the formation of the additional peaks as revealed in FTIR. Furthermore, the prepared hybrid nanocomposites showed a decreased contact angle of 51°±1.32° indicating a hydrophilic nature and exhibited lower thermal stability compared to pristine PVA. Moreover, the mechanical results revealed that the electrospun scaffold showed an improved tensile strength of 3.55±0.29 MPa compared with the pristine PVA (1.8±0.52 MPa). The prepared hybrid nanocomposites showed delayed blood clotting as noted in APTT and PT assays indicating better blood compatibility. Moreover, the hemolysis assay revealed that the hybrid nanocomposites exhibited a low hemolytic index of 0.6% compared with pure PVA, which was 1.6% suggesting the safety of the developed nanocomposite to red blood cells (RBCs).

Conclusion

The prepared nanocomposites exhibited better physico-chemical properties, sufficient porosity, mechanical strength, and blood compatibility, which favors it as a valuable candidate in bone tissue engineering for repairing the bone defects.

Surface, thermal and hemocompatible properties of novel single stage electrospun nanocomposites comprising polyurethane blended with bio oilTM

In this work, the physicochemical and blood compatibility properties of prepared PU/Bio oil nanocomposites were investigated. Scanning electron microscope (SEM) studies revealed the reduction of mean fiber diameter (709 ± 211 nm) compared to the pristine PU (969 nm ± 217 nm). Fourier transform infrared spectroscopy (FTIR) analysis exposed the characteristic peaks of pristine PU. Composite peak intensities were decreased insinuating the interaction of the bio oilTM with the PU. Contact angle analysis portrayed the hydrophobic nature of the fabricated patch compared to pristine PU. Thermal gravimetric analysis (TGA) depicted the better thermal stability of the novel nanocomposite patch and its different thermal behavior in contrast with the pristine PU. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness of the composite patch. Activated partial thromboplastin time (APTT) and prothrombin time (PT) signified the novel nanocomposite patch ability in reducing the thrombogenicity and promoting the anticoagulant nature. Finally the hemolytic percentage of the fabricated composite was in the acceptable range revealing its safety and compatibility with the red blood cells. To reinstate, the fabricated patch renders promising physicochemical and blood compatible nature making it a new putative candidate for wound healing application.