Bioactivity of wollastonite/aerogels composites obtained from a TEOS-MTES matrix

Biodegradable Polycaprolactone Fibers with Silica Aerogel and Nanosilver Particles Produce a Coagulation Effect

Poly-ε-caprolactone (PCL) is a biodegradable aliphatic polyester that can be used in the field of biomaterials. Electrospinning is the name given to the process of producing micro and nanoscale fibers using electrostatically charged polymeric solutions under certain conditions. Almost all synthetic and naturally occurring polymers can undergo electrospinning using suitable solvents or mixtures prepared in certain proportions. In this study, silica aerogels were obtained by the sol-gel method. PCL-silica aerogel fibers were synthesized by adding 0.5, 1, 2, and 4% ratios in the PCL solution. Blood contact analysis was performed on the produced fibers with UV-VIS. According to the results obtained, 0.5, 1, 2, and 4% nano-silver were added to the fiber-containing 4% aerogel. Then, SEM-EDS and FTIR analyses were performed on all fibers produced. Antimicrobial tests were performed on fibers containing nano-silver. As a result, high-performance blood coagulation fibers were developed using PCL with aerogel, and an antimicrobial effect was achieved with nano-silver particles. It is thought that the designed surface will be preferred in wound dressing and biomaterial in tissue engineering, as it provides a high amount of cell adhesion with a small amount of blood and contains antimicrobial properties.

Vacuum sealing drainage system combined with an antibacterial jackfruit aerogel wound dressing and 3D printed fixation device for infections of skin soft tissue injuries

Injuries and infections of skin and soft tissue are commonly encountered in primary health care and are challenging to manage. Vacuum sealing drainage (VSD) is generally used in clinical treatment, but current commercial methods of VSD have some disadvantages, such as easy blockage, nonantibacterial effects, and inconvenient curved surfaces. Herein, we report a functional zinc oxide/jackfruit aerogel (ZnO/JFA) composite material that is ultralight, superabsorbent and antibacterial as a new antibacterial VSD wound dressing. The JFA is carbonized from fresh jackfruit, and the JFA exhibits superhydrophilicity and superabsorbability. The water absorption rate of JFA was up to 1209.39%, and the SBF absorption rate was up to 1384.22%. The water absorption rate of ZnO/JFA was up to 494.47%, and the SBF absorption rate was up to 473.71%. The JFA and ZnO/JFA possess a pipeline structure, which is beneficial for absorbing wound exudates. In addition, surface modification of nanosized ZnO and its effects on antibacterial properties and biocompatibility were performed. When the concentration of ZnO/JFA was 3.125 mg/mL, the survival rate of human fibroblast cells was close to 80%, while the antibacterial rates against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were up to 99.06%, 75.28% and 93.58%, respectively. Moreover, a 3D printed assisted device was introduced to make the ZnO/JFA wound dressing more attached to the bottom of the wound on a curved surface. An integrated device was formed under the printing mold, and then animal experiments were conducted in vivo. The results showed that a healing rate of almost 100% for infected skin wounds was obtained with this novel VSD device after 14 days, compared to only 79.65% without the VSD device. This novel VSD with a negative pressure suction dressing is beneficial for healing infectious wounds.

Fabrication of Porous Alumina Structures by SPS and Carbon Sacrificial Template for Bone Regeneration

In this work, a procedure for fabricating porous alumina with the use of a carbon sacrificial template has been tested in order to optimize the fabrication of porous structures mimicking the porosity and mechanical properties of the human cortical bone. Two different sources of sacrificial carbon were used and compared, and different sintering and calcination routes were considered. The porosity of the alumina structures studied by Hg porosimetry revealed that the amount of porosity and the size and shape of the pores are still below the required values, although some acicular pores were clearly observed by SEM. Moreover, measured mechanical properties (Young’s modulus) remained below that of the bone, suggesting the need for further consolidation treatments. In summary, these encouraging results drive the optimization of future fabrication routes.

Synthesis and biomedical applications of aerogels: Possibilities and challenges

Aerogels are an exceptional group of nanoporous materials with outstanding physicochemical properties. Due to their unique physical, chemical, and mechanical properties, aerogels are recognized as promising candidates for diverse applications including, thermal insulation, catalysis, environmental cleaning up, chemical sensors, acoustic transducers, energy storage devices, metal casting molds and water repellant coatings. Here, we have provided a comprehensive overview on the synthesis, processing and drying methods of the mostly investigated types of aerogels used in the biological and biomedical contexts, including silica aerogels, silica-polymer composites, polymeric and biopolymer aerogels. In addition, the very recent challenges on these aerogels with regard to their applicability in biomedical field as well as for personalized medicine applications are considered and explained in detail.