Influence of carbon nanotubes on the antimicrobial character of the β-lactam antibiotics Cefepime and Meropenem

The overuse of antibiotics over decades has led to a multi-resistance of bacteria that today poses a serious threat to human health. β-lactam antibiotics are one of the most prescribed drugs against bacterial infectious diseases, which has conducted to increased resistance. The short half-life of these drugs results in low bioavailability, which limits their clinical use and requires continuous administration by infusion. Encapsulation of these antibiotics in nanocarriers would improve their biopharmaceutical properties by protecting them. With this in mind, single- and multi-walled carbon nanotubes (SWCNTs and MWCNTs, respectively) were used here as nanocarriers for the antibiotics Meropenem and Cefepime. The adsorption process of these antibiotics in the carbon nanotubes (CNTs) was optimized to obtain a high encapsulation efficiency. The complexes CNT/drug prepared were characterized by dynamic light scattering and spectroscopic measurements. The growth of Escherichia coli and Staphylococcus aureus bacteria was analyzed in the presence of the CNT/drug complexes to evaluate the pharmacological properties of the encapsulated antibiotics. Results showed lower minimum inhibitory concentration (MIC) values of the CNT/drug complexes compared to free drugs. This indicates the preservation of the pharmacological properties of the encapsulated antibiotics. In addition, the stability of the encapsulated antibiotics was observed to last at least 24 h, which was a great improvement compared to the free drugs. • CNTs are suitable nanocarriers for the controlled delivery of Cefepime and Meropenem. • Cefepime and Meropenem encapsulated in CNTs maintain their antimicrobial activity. • CNT/β-lactam antibiotic complexes increase the drug half-life time for at least 24 h.