Electrospun soy protein isolate mats: Effects of sterilization by UV radiation on scaffold properties

M. POPOV; P.C. CARACCIOLO; G.A. ABRAHAM

Sao Paulo

Encuentro; II Encontro de Polimeros Naturais (II EPNAT); 2020

The solution electrospinning technique is very versatile for obtaining micro/nanofiber matrices from polymer solutions. These matrices have a high surface-volume ratio; a complex porous structure with interconnected pores; and different fibrous morphologies; these features show similarities to the extracellular matrix, which is ideal for cell adhesion and proliferation. Due to these advantages, electrospun structures are of great interest for tissue engineering applications. Among natural polymers, some studies showed interesting results of electrospun soy protein isolate (SPI) for biomedical applications. Furthermore, the development of biomedical devices requires material stability against sterilization process. There are different methods: thermal (autoclave), chemical (ethylene oxide), radiation (UV, e-beam or gamma rays). Due to the instability of the SPI upon autoclaving and ethylene oxide techniques, the feasibility of using UV radiation (254 nm) as an alternative to sterilize electrospun membranes based on SPI was studied. Bilayer matrices (SPI-PEO/PCL) were obtained using an electrospinning device equipped with a rotating drum as collector. An electric field of 0.55-0.8 kV/cm, a flow rate of 0.2-0.5 mL/h and a collector rotation speed of 300-1200 rpm were used. The membranes were exposed to UV radiation (254 nm) for different times: 10, 20 and 40 minutes. Scanning electron microscopy (SEM) micrographs showed a continuous fibrous structure in all samples, no structural damage was observed after exposure to UV radiation at different period of time. Differential scanning calorimetry (DSC) experiments were also carried out and thermal properties did not undergo significant alterations after exposure to UV radiation. In conclusion, the exposure to UV-radiation did not change the SPI-based electrospun properties, being a feasible method for sterilizing these membranes