Poly (3-hydroxybutyrate-co-3-hydroxyvalerate)/fibrinogen/bredigite nanofibrous membranes and their integration with osteoblasts for guided bone regeneration.

Guided bone regeneration (GBR) has been established to be an effective method for the repair of defective tissues, which is based on isolating bone defects with a barrier membrane for faster tissue reconstruction. The aim of the present study is to develop poly (hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/fibrinogen (FG)/bredigite (BR) membranes with applicability in GBR. BR nanoparticles were synthesized through a sol-gel method and characterized using transmission electron microscopy and X-ray diffractometer. PHBV, PHBV/FG, and PHBV/FG/BR membranes were fabricated using electrospinning and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, contact angle, pore size, thermogravimetric analysis and tensile strength. The electrospun PHBV, PHBV/FG, and PHBV/FG/BR nanofibers were successfully obtained with the mean diameter ranging 240-410 nm. The results showed that Young's modulus and ultimate strength of the PHBV membrane reduced upon blending with FG and increased by further incorporation of BR nanoparticles, Moreover hydrophilicity of the PHBV membrane improved on addition of FG and BR. The in vitro degradation assay demonstrated that incorporation of FG and BR into PHBV matrix increased its hydrolytic degradation. Cell-membrane interactions were studied by culturing human fetal osteoblast cells on the fabricated membrane. According to the obtained results, osteoblasts seeded on PHBV/FG/BR displayed higher cell adhesion and proliferation compared to PHBV and PHBV/FG membrane. Furthermore, alkaline phosphatase activity and alizarin red-s staining indicated enhanced osteogenic differentiation and mineralization of cells on PHBV/FG/BR membranes. The results demonstrated that developed electrospun PHBV/FG/BR nanofibrous mats have desired potential as a barrier membrane for guided bone tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1154-1165, 2019.

Nanofibrous Tubular Membrane for Blood Hemodialysis.

As the most important components of a hemodialysis device, nanofibrous membranes enjoy high interconnected porosity and specific surface area as well as excellect permeability. In this study, a tubular nanofibrous membrane of polysulfone nanofibers was produced via electrospinning method to remove urea and creatinine from urine and blood serums of dialysis patients. Nanofibrous membranes were electrospun at a concentration of 11.5 wt% of polysulfone (PS) and dimethylformamide (DMF)/tetrahydrofuran (THF) with a ratio of 70/30. The effects of the rotational speed of collectors, electrospinning duration, and inner diameter of the tubular nanofibrous membrane on the urea and creatinine removal efficiency of the tubular membrane were investigated through the hemodialysis simulation experiments. It was found that the tubular membrane with an inner diameter of 3 mm elecrospun at shorter duration with lower collecting speed had the highest urea and creatinine removal efficiency. The hemodialysis simulation experiment showed that the urea and creatinine removal efficiency of the tubular membrane with a diameter of 3 mm were 90.4 and 100%, respectively. Also, three patients' blood serums were tested with the nanofibrous membrane. The results showed that the creatinine and urea removal rates were 93.2 and 90.3%, respectively.

Advances in electrospun nanofibers for bone and cartilage regeneration.

Regeneration of bone and cartilage tissues has been an important issue for biological repair in the field of regenerative medicine. The rapidly emerging field of tissue engineering holds great promise for repair and generation of functional bone and cartilage substitutes with a combination of biomaterials, cells, drugs and growth factors. Scaffolds play a pivotal role in tissue engineering as they mimic the natural extracellular matrix (ECM) and play an important role in guiding cell adhesion and proliferation, and maintaining the normal phenotype of the tissues. The use of tissue-engineered grafts based on scaffolds has found to be a more effective method than conventional implantations of autograft, allograft, xenograft. In recent years much attention has been given to electrospinning as a feasible and versatile technique for fabrication of nanofibrous scaffolds, with large surface area to volume ratio, high porosity, mechanical properties and physical dimension similar to the ECM of natural tissues. Extensive research has been carried out for fabrication polymeric nanofibrous substrates with incorporation of hydroxyapatite nanoparticles or bone morphogenetic protein molecules for efficient tissue repair. Here we review on the literature of electrospun nanofibrous scaffolds, their modifications, and advances aimed towards the rapid regeneration of bone and cartilage.