TiO2-grafted cellulose bio-nanocomposite (Cell.Com) was successfully prepared by combining modified cellulose and TiO2 nanoparticles via copper-catalyzed alkyne-azide click reaction. The antibacterial and cytotoxicity effects of Cell.Com containing cellulose, triazole ring and TiO2 moieties are reported in this work. The antibacterial activity of Cell.Com was investigated against gram positive (S. aureus and B. subtilis) and gram negative (E. coli and P. aeruginosa) bacteria. The antibacterial results indicate that the Cell.Com exhibits a wide range of antibacterial activity against both gram positive and gram negative bacteria which is due to the presence of TiO2 and triazole ring moieties in its structure. In addition, the cytotoxicity effect of Cell.Com was studied in vitro on cervical cancer (HeLa), breast carcinoma (MCF-7), sarcoma osteogenic (Saos) and fibroblast cells by MTT assay. The cell viability results show that the Cell. Com diminishes relatively cancer cells growth in a dosage and time dependent way probably through triazole moiety, while no apparentcytotoxicity effect is observed on the normal fibroblast cells. تفاصيل المقالة