TWO-STEP CROSSLINKING OF PVP/GEL NANOFIBERS

In this study, it was achieved that crosslinking of PVP/GEL nanofibers with two-steps. Crosslinking is a process highly important for water-soluble polymers in terms of application areas and mechanical properties. Firstly, crosslinking of PVP polymers experimental studies were carried out via heat treatment at different temperatures and times. Then, GEL polymers were crosslinked with GTA vapour at different times. Morphological analysis was carried out via SEM images and chemical characteristics were determined via FT-IR analysis. Moreover, after the crosslinking process, SD and WL values were calculated. All results showed that before crosslinking of SEM images, nanofibers were smooth, fine and without beads. The average fiber diameter is 196 nm and the fiber diameter distribution is quite uniform. After crosslinking of SEM images, it is expected that all nanowebs will turn from fibrous surfaces to membranous. Generally, SD and WL values decrease with crosslinking time increase. According to all of the SEM images, SD and WL values, optimum conditions were determined for PVP as 4 hours at 180oC and for GEL as 24 hours. Lastly, the presence of PVP and GEL polymers in the nanofiber structure was verified chemically with FT-IR analysis.

HYDRO-GEL POLYMERS AND 3D BIOPRINTING IN SKIN ENGINEERING - A REVIEW

Tissue engineering is a booming field of science and technology. The sheer potential it emanates is enough to place all attention on it. Tissue engineering is widely researched for the development of skin substitutes to treat patients with infections or disorders. Commercial skin substitutes provide a promising future to medicine. The availability of different biomaterials for the production of artificial skin has posed many questions regarding the feasibility, usability, and practicality of these products. The articles reviewed discuss tissue engineering as a challenging field and how skin substitutes are vital. Biomaterials and hydrogel studies are found to be a game changer for the field. The functional aspects have been discussed with the physical characteristics for better understanding. Different techniques of printing biological structures by using scaffolds are discussed in detail. Scaffolds provide a very efficient structural composition for the bioprinter to manifest the organ to be printed. Bioink composition and preparation with scientific knowledge make it a very important asset in tissue engineering. The future of regenerative medicine and organ transplantation is expected to be safe within the various aspects of tissue engineering. The vast possibilities it offers is hard to not explore further. Even though the research field has come a long way since the beginning of tissue culture in the 1970s, there are still different challenges to be faced and conquered.

IN SITU GEL POLYMERS: A REVIEW

In situ gels have become one of the most prominent and accessible systems. These systems have several advantages like simple manufacturing, easy to use, improved adherence, and patient comfort by minimizing drug administration frequency by its unique characteristic features of sol to gel transition. In the 'sol-gel' method, the precursor goes through hydrolysis and polymerization or condensation to produce a colloidal suspension or solution. As they can administer in solution form, these in situ gelling systems undergo gelation at the achievement site. Some researchers recently developed in situ gelling systems of liposomes, microspheres, nanoemulsions, nanospheres, etc. This review mainly focused on the introduction, advantages, disadvantages, types of polymers, and suitable characteristics for preparing in situ gels.