Antimicrobial efficacy of carbon nanotube-based nano drug on Escherichia coli and expression of Acr AB gene involved in bacterial drug resistance

The most common form of nosocomial infection is urinary tract infection, which is more prevalent among women. E. coli has been known as the main agent involved in urinary tract infections, and Ampicillin (AMP) is usually prescribed for the treatment of this infection. Due to the development of antibiotic resistance as a result of consuming conventional antibiotics, modification of pure drugs has been recommended as a solution to this problem. The main purpose of this study is to prepare AMP-conjugated nanofluids containing carbon nanotubes for enhanced drug performance as well as the prevention of antibiotic resistance. In this study, thionyl chloride has been used as an agent for the activation of multi-walled carbon nanotubes (MWCNTs) through a reflux system. Moreover, nanofluids containing antibiotics were prepared through an ultrasonic approach. Different methodologies, including general element analysis, infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy, have been applied to study the properties of the nano-drugs that were prepared. Following the treatment of the desired strain with the nanofluid, microbial studies were performed to evaluate the respective antibacterial effects. Finally, the AcrAB resistance gene expression has been assessed. The results showed that the antimicrobial effect of functionalized MWCNTs with AMP (AMP-MWCNT) at low concentrations is higher than that of conventional drugs in both resistant and standard strains. Compared to the pure drug, a significant reduction in bacterial antibiotic resistance under AMP-MWCNT treatment has been observed. It was also found that the AcrAB gene expression decreases in bacteria treated with AMP-MWCNT. Our study shows that the antimicrobial effect of low-concentration AMP-MWCNT is greater than that of the conventional drug used in resistant strains. A decrease in antibiotic resistance of bacteria treated with AMP-MWCNT was also observed compared to the free drug. Moreover, the AcrAB gene expression was found to be decreased in bacteria treated with AMP-MWCNT. • The main purpose of this study is to Nano-delivery of AMP to overcoming antibiotic resistance of E. coli. • Antimicrobial effect of low-concentration AMP-MWCNT is greater than that of the conventional drug used in resistant strains. • A decrease in antibiotic resistance of bacteria treated with AMP-MWCNT observed compared to the free drug. • The AcrAB gene expression was found to be decreased in bacteria treated with AMP-MWCNT.