Synthesis of antibacterially bioinorganic composite by immobilising lysozymes in layered titanates

Abstract

An antibacterially bioinorganic composite has been synthesised by intercalating lysozymes (LZs) into layered titanates with a convenient and efficient exfoliation-restacking strategy. This composite exhibits a loose slab morphology with a thickness of 5-10 layers, and the interlayer space is ∼4.4 nm because of intercalation of enzymes. The immobilised amount of lysozymes is up to ∼68.3% in weight because of the layer-by-layer alternate and swollen structure. This composite is stable in the neutral and weakly acidic condition, and only releases <10% of lysozymes in the pH > 4 solution. The immobilised LZs exhibit excellent thermal stability, which retain their initial activities of about 70% at 70°C for about 40 min. In addition, the residual activities of the immobilised enzymes are 68% after ten recycles reuse.