Despite the modern medicinal chemistry in designing new therapeutic agents by using different new innovative techniques in molecular modeling and combinatorial chemistry, beside to their expensive cost, infectious diseases continue to be one of the greatest health challenges worldwide, the demand toward alternative agents is continuously increasing. Recent advancement in nanotechnology has expanded our ability to design and construct nanomaterials to treat bacterial infections. Carbon nanotubes are one among these nanomaterials. Herein, we describe the development of new nanoantibiotic based on the covalent functionalization of the single-walled carbon nanotubes (SWCNTs) with multiple molecules of ciprofloxacin. The prepared nanoantibiotics were characterized using different techniques, including transmission electron microscopy, thermogravimetric analysis and Raman spectroscopy. The characterization of the nanoantibiotic confirmed the successful covalent functionalization of the SWCNTs with a good release profile at pH 7.4. Interestingly, the results of the antibacterial activity indicated that the functionalized SWCNTs have significant increase in the antibacterial activity against the three tested strains of bacteria – Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli – in comparison to the ciprofloxacin free drug. Moreover, the synthesized nanoantibiotic showed high hemocompatibility and cytocompatibility over a wide concentration range.