Fluorescence spectroscopy and isothermal titration calorimetry, two powerful methods for detecting molecular interactions, are used, for the first time, to study the interaction between these nanoparticles and a model of their cellular receptor.

Chlamydia trachomatis is responsible for the most frequent sexually transmitted bacterial infection in the world and for trachoma, the world's leading infectious cause of blindness. Genital chlamydial infection is very common among sexually active young people, and when untreated, leads to serious complications. No vaccine is available. Although Chlamydia resistance to antibiotics is rarely observed in vivo, studies showed that 10-20% of patients remain infected at the end of antibiotherapy, without being reinfected. The present review gives a global and comprehensive overview of the different targets and the related inhibitors proposed during the last decade, with a view to limiting the growth of this human pathogen. Metallic and polymeric nanoparticles in this field are also briefly presented.

Chlamydia trachomatis causes the most common sexually transmitted bacterial infection and trachoma, an eye infection. Untreated infections can lead to sequelae, such as infertility and ectopic pregnancy in women and blindness. We previously enhanced the antichlamydial activity of the fluoroquinolone ciprofloxacin by grafting a metal chelating moiety onto it. In the present study, we pursued this pharmacomodulation and obtained nanomolar active molecules (EC₅₀) against this pathogen. This gain in activity prompted us to evaluate the antibacterial activity of this family of molecules against other pathogenic bacteria, such as Neisseria gonorrhoeae and bacteria from the ESKAPE group. The results show that the novel molecules have selectively improved activity against C. trachomatis and demonstrate how the antichlamydial effect of fluoroquinolones can be enhanced.