Robust biocompatible bacterial cellulose/silk nonwoven fabric/silk sericin sandwich membrane with strong UV-blocking and antioxidant properties

Kombucha-derived bacterial cellulose (KBC) is a unique natural polysaccharide that has gained increasing interest in biomedical and other applications. However, the relatively low bioactivity of the product has limited its practical applications. In this work, KBC and silk nonwoven fabric (SNF) were integrated to produce a sandwich membrane through in situ growth of KBC in the presence of SNF. Scanning electron microscopy (SEM) showed that KBC grew not only on the surface of SNF but also within the fiber network of SNF. The strength and modulus of SNF were significantly increased after the integration of KBC. The KBC/SNF sandwich membrane was further impregnated with silk sericin (SS) through simple solution absorption to impart strong UV shielding property to the material, which was demonstrated by the near zero UV transmittance of the new KBC/SNF-SS membrane. SEM, Fourier transform infrared spectrometry, and X-ray diffraction results indicated the interactions between the three components. DPPH (2,2-Diphenyl-1-picrylhydrazl) radical scavenging test and cytotoxicity test showed strong antioxidant activity and biocompatibility of the new membrane due to the presence of SNF and SS. These properties make this new biocomposite membrane a promising material for healthcare and skincare applications, such as wound dressing and beauty products. Graphical abstract