EFFICACY AND SAFETY OF SILVER NANOCOMPOSITES ON RIFAMPICIN-RESISTANT M. TUBERCULOSIS STRAINS.

Background: Control of rifampicin-resistant tuberculosis (RR-MTB) requires novel technologies for restoring the anti-TB efficacy of priority drugs. We sought to evaluate the ability of nanotechnology application in the recovery of the anti-tuberculosis efficacy of rifampicin.

Methods: Nanocomposite- standard dose of rifampicin and 20 nm silver nanoparticles (AgNPs) suspension solution of 6 different concentrations: 0.25%; 0.5%; 1%; 2.5%; 5%; and 10%, were supplemented to 70 rifampicin-resistant mycobacterium tuberculosis (RR-MTB) isolates. The control arm consisted of 35 RR-MTB isolates and AgNPs suspension with identical concentrations. The inhibitory effect of nanocomposites was evaluated by MTB growth rate using the BACTECTM MGIT 960TM. The safety assessment of single-use AgNPs was conducted in experimental animals.

Results: The suppression process of AgNPs on RR-MTB isolates started with 2,5% nanocomposite solution application and full suppression was achieved in 5% and 10% nanocomposite solutions. A standard dose of rifampicin and a 2.5% solution of AgNPs increased the minimal inhibitory effect on RR-MTB by 10% (total 80%) vs the isolated use of a 2.5% solution of AgNPs (70%). An experiment on animals revealed the complete safety of a single injection of ultra-high doses of AgNPs.

Conclusion: The study showed the potentiating effect of AgNPs in overcoming the resistance of MTB to rifampicin providing a scientific basis for further research.