Bacterial cellulose nanofibrils-armored Pickering emulsions with limited influx of metal ions

This study introduces a hydrophobically modified bacterial cellulose nanofibrils (BCNF)-stabilized Pickering emulsion system, which can limit the influx of metal ions through the interface. We showed that the C18 alkyl chain-grafted BCNF (_C18BCNF) can readily associate to generate a resilient thin membrane at the oil-water interface regardless of the type of oil, which is essential for the production of stable emulsion drops. The viscoelasticity of _C18BCNF-armored Pickering emulsion was feasibly tunable by manipulating the grafting amount of the C18 alkyl chains, as well as controlling the _C18BCNF concentration. We also demonstrated that the _C18BCNF membrane formed at the interface effectively entrapped metal ions through electrostatic binding with the carboxyl groups on _C18BCNF, thus maintaining original UV-absorbing capability of chemical UV filter-containing emulsions. We expect that the BCNF surfactant fabricated in this study has immense potential for the development of various complex emulsion products.