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Fabrication of three dimensional (3D) tissue engineering scaffolds, particularly for hard tissues remains a challenge. Electrospinning has been used to fabricate scaffolds made from polymeric materials which are suitable for hard tissues. The electrospun scaffolds also have structural arrangement that mimics the natural extracellular matrix. However, electrospinning has a limitation in terms of scaffold layer thickness that it can fabricate. Combining electrospinning with other processes is the way forward, and in this proposed technique, the basic shape of the scaffold is obtained by a fused deposition modelling (FDM) three dimensional (3D) printing machine using the partially hydrolysed polyvinyl alcohol (PVA) as the filament material. The 3D printed PVA becomes a template to be placed inside a mould which is then filled with the fully hydrolysed PVA/maghemite (γ-Fe 2 O 3 ) solution. After the content in the mould solidified, the mould is opened and the content is freeze dried and immersed in water to dissolve the template. The 3D structure made of PVA/maghemite is then layered by electrospun PVA/maghemite fibers, resulting in 3D tissue engineering scaffold made from PVA/maghemite. The morphology and mechanical properties (strength and stiffness) were analysed and in vitro tests by degradation test and cell penetration were also performed. It was revealed that internally, the 3D scaffold has milli-and microporous structures whilst externally; it has a nanoporous structure as a result of the electrospun layer. The 3D scaffold has a compressive strength of 78.7 ± 0.6 MPa and a Young's modulus of 1.43 ± 0.82 GPa, which are within the expected range for hard tissue engineering scaffolds. Initial biocompatibility tests on cell penetration revealed that the scaffold can support growth of human fibroblast cells. Overall, the proposed processing technique which combines 3D printing process, thermal inversion phase separation (TIPS) method and electrospinning process has the potential for producing hard tissue engineering 3D scaffolds.

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This study proposed a new mixture of three different biocompatible and biodegradable materials for soft tissue which needs elasticity and stretchability as well as stiffness. Five different ratios of poly-L-lactic acid (PLLA)/thermoplastic polyurethane (TPU) blend containing 1 % (w/v) maghemite (c-Fe 2 O 3 ) nanoparticles were electrospun and characterized in terms of morphology, degradation rate, biological compatibility, and mechanical properties for tunable properties. Neat PLLA/TPU samples were used for maghemite effect verification. The existence of three components in the electrospun mats was confirmed by Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. Scanning electron microscopy images illustrated well-fabricated nanofibers with smaller diameter distribution for PLLA. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay using human skin fibroblast cell indicates desired proliferation and migrant over the samples. Blood biocompatibility results in terms of clotting time, fibrin formation, and hemolysis were almost in the normal range. Samples' degradation rate was investigated over 24 weeks where the PLLA shows 47.15 % mass change, while 6.7 % of TPU mass changed. High tensile strength and an extremely low elongation at break were determined from the stress-strain curve for PLLA, while TPU exhibits high elasticity. The 50:50 % ratio of 1 % (w/v) maghemite-loaded PLLA/TPU scaffold presents an overall satisfaction.

Valvular dysfunction as the prominent reason of heart failure may causes morbidity and mortality around the world. The inability of human body to regenerate the defected heart valves necessitates the development of the artificial prosthesis to be replaced. Besides, the lack of capacity to grow, repair or remodel of an artificial valves and biological difficulty such as infection or inflammation make the development of tissue engineering heart valve (TEHV) concept. This research presented the use of compound of poly-L-lactic acid (PLLA), thermoplastic polyurethane (TPU) and maghemite nanoparticle (γ-Fe 2 O 3 ) as the potential biomaterials to develop three-dimensional (3D) aortic heart valve scaffold. Electrospinning was used for fabricating the 3D scaffold. The steepest ascent followed by the response surface methodology was used to optimize the electrospinning parameters involved in terms of elastic modulus. The structural and porosity properties of fabricated scaffold were characterized using FE-SEM and liquid displacement technique, respectively. The 3D scaffold was then seeded with aortic smooth muscle cells (AOSMCs) and biological behavior in terms of cell attachment and proliferation during 34 days of incubation was characterized using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and confocal laser microscopy. Furthermore, the mechanical properties in terms of elastic modulus and stiffness were investigated after cell seeding through macro-indentation test. The analysis indicated the formation of ultrafine quality of nanofibers with diameter distribution of 178 ± 45 nm and 90.72% porosity. In terms of cell proliferation, the results exhibited desirable proliferation (109.32 ± 3.22% compared to the control) of cells over the 3D scaffold in 34 days of incubation. The elastic modulus and stiffness index after cell seeding were founded to be 22.78 ± 2.12 MPa and 1490.9 ± 12 Nmm 2 , respectively. Overall, the fabricated 3D scaffold exhibits desirable structural, biological and mechanical properties and has the potential to be used in vivo.

Magnetic nanofibers were fabricated using polyvinyl alcohol as a shelter for magnetic nanoparticles suspension. The transformation process from ferrofluid and polyvinyl alcohol solution to magnetic nanofibers has been investigated where the response variable analyzed was morphology. The results obtained from the high resolution transmission electron microscopy observation revealed that the flow rate and voltage have significant effect on desirable morphology. Nanofibers with fancy morphology and better aligned order tend to have higher elasticity contributed by the better alignment of lamellae along the fibers axis and molecular orientation. The fabricated nanofibers were ultra-fine with nanosize diameter within the range of approximately 290-380 nm.