Inverse Opal Scaffolds with an Embossed Surface Pattern Prepared from Sticky Golf-Ball-Shaped Microparticle Assemblies

Abstract

Inverse opal scaffolds presenting an embossed-pattern surface are prepared from colloidal crystal assemblies of uniformly sized golf-ball-shaped microparticles. Post-treatments, such as thermal annealing during the bridging of the microparticles for opal preparation, are avoided to prevent deterioration of surface patterns of the sacrificial template. This presents a new approach to increase the surface-area-to-volume ratio (SAV) by the alteration of morphological features in sophisticated 3D structures that remain largely unexamined owing to difficulties in their preparation. Previous results observed in 2D surfaces that show effective performance improvement through an increase in contact area, especially in biomedical applications, also appear applicable to patterned inverse opal scaffolds based on comparable results obtained from cell cultures. As the field of application of opal and inverse opal structures is expanding due to their unique structural advantages, such as 3D interconnectivity and periodic structures, our strategy opens the door for the use of patterned surfaces on highly sophisticated 3D structures, improving their performance via an increase in SAV.