Electrospraying of environmentally sustainable alginate microbeads for cosmetic additives

Polymer microbeads (MBs) for scrubbing additives have generally been prepared from non-biodegradable synthetic polymers. The worldwide pollution of the marine ecosystem by microplastics urgently demands novel environment-friendly MBs. In this study, Ca-alginate MBs were fabricated by electrospraying an aqueous alginate solution into distilled water containing calcium ions. The size and shape of the Ca-alginate MBs were controlled by electrospraying parameters, such as nozzle diameter and solution concentration. As the alginate concentration and needle diameter were increased, the size of alginate MBs was gradually increased, because of the higher mass flow rate. In addition, the adsorption and degradation behavior of alginate MBs were examined using model contaminants and sea water, respectively. In particular, alginate MBs rapidly degraded in sea water, due to the reversible ion-exchange reaction between Ca²⁺ in MBs and Na⁺ in sea water. Therefore, the electrosprayed Ca-alginate MBs offer a promising alternative for environment-friendly cosmetic additives.