Functional Cellulose Microspheres for Potential Biomedical and Cosmetological Applications

Cellulose microspheres2 (CMs, alt. cellulose beads) are cellulosic microparticles with diameters in the 10-1000 µm range. These biodegradable microparticles have been used as stationary phases in regular, reversed phase, size exclusion and ion exchange chromatographies, and as supports for protein immobilization, solid-phase synthesis, and pharmaceutical loading and release. Furthermore, since cellulose and CMs are very biocompatible, they have been used in some biomedical applications such as the dressing of wounds and blood filtration for removal of toxins. There has recently been a renewed interest in CMs (and microparticles from similar materials)3 as they could be used as an alternative to similarly sized plastic microbeads (PMs) employed in cosmetic formulations as colorizing, exfoliating, and texturizing agents. PMs in cosmetic formulations are being phased out globally due to the acute environmental damage caused by microplastics pollution in aquatic ecosystems.4In the first part of this talk we will summarize some of our findings regarding the size controlled preparation of CMs through thermal regeneration of cellulose from water-in-oil emulsions of viscose (Figure 1; A, B). In the second part, we will focus on the potential biomedical applications of functionalized CMs by demonstrating the ability of CMs, which were covalently derivatized with a targeting group, to bind to negatively charged liposomes and bacterial cells (Figure 1; C, D). In the final part, we will discuss the preparation of CMs with various functional qualities such as buoyancy, color, and magnetism, and demonstrate their cosmetological utility by presenting two distinct and novel cosmetic formulations employing functional CMs (Figure 1; E). We believe that functional CMs will play important future roles in biomedical and environmental applications as well as in cosmetic formulations.