Effect of Modified Solvent Casting/Particulate Leaching (SCPL) Technique on the Properties of Bioactive Glass Reinforced Polyurethane Scaffold for Biomedical Applications


Salt leaching technique is commonly used in the preparation of porous scaffolds for tissue engineering due to easy control of pore structure. However, distribution of the salt particles within polymer solution using this technique is difficult to be controlled and causes a problem of residual salt in scaffolds. Solvent casting technique is often combined with salt leaching technique to produce porous scaffold. In this present work, modification of solvent casting/particulate leaching (SCPL) technique was developed which involved a conventional SCPL method combined with a step of centrifugation using different centrifugal speeds of 1500 rpm, 2000 rpm, 2500 rpm and 3000 rpm to produce 45S5 bioactive glass (BG) reinforced polyurethane (PU) scaffolds. PU-BG scaffolds were fabricated with mass ratio of 90PU:10BG and with 52 wt% hard segment content of PU. Sodium chloride (NaCl) and sodium bicarbonate (NaHCO3) were used as the leaching agent to create pores in the scaffolds. The physical, structural, morphological and mechanical properties of scaffolds were studied by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX), porosity test and compression test. Highly porous scaffolds with good interconnectivity were obtained by enhanced SCPL method with porosity ranging from 88% to 90%. The porosity increased with an increase in the centrifugal speed up to 2500 rpm. While the mechanical properties of the scaffolds were compromised as lower compressive strength ranging from 0.17 Mpa to 0.66 MPa were obtained by modified SCPL method as compared to 0.90 MPa by conventional SCPL method.