Efficiency of Rifampin-loaded chitosan NPs in Killing of Brucella melitensis Isolated From Aborted Sheep in Wasit Province, Iraq

Abstract

Brucellosis is consider one of the utmost common bacterial infectious illness that infect man and animals. unfortunately, A worldwide community in the developing country didn't provide active assistance for reducing it spread out globally. Therefore, the aim of this study is the synthesis of chitosan nanoparticles loaded with rifampin to overcome bacterial resistance and provide high intracellular penetration and the potential for potent intracellular antibacterial activity. The study was conducted from October 2019 to September 2021, Of 57 positive clinical specimens identified in the present study, 25 (65.78%), 20 (74.07%), and 12 (66.66%) were isolated from vaginal swabs, fetal membranes, and fetal abomasum contents, respectively. From the results of SEM images of NPs, it was clear that RIF-loaded CHNPs presented irregular surfaces or rough with spherical shape and presence of some particle aggregates. The RIF-CHNPs particle size observed using SEM images was 260.54 nm, while the diameter was 150.23 nm. In addition, the antibacterial activity were also measured and the results shows that the MIC values for RIF, CHNPs and RIF-CHNPs and they were 4, 2.5 and 0.625 ug/ml, respectively. While the EE % and DL % of RIF were measured spectrophotometrically. Loaded antibiotic formulation gave good percentage of entrapment efficiency and drug loading at concentration 50 mg/ml. Then the EE % at concentration 50 mg/ml was re-estimated in different pH values and the best EE% was at pH 5. In conclusion, the antibacterial activity of drug nanocarrier against B. melitensis found that it had a relatively low MIC 0.625 ug/ml. whereas the inhibitory concentrations were about 4 μg/ml and 2.5 μg/ml for the RIF and CHTNPs, respectively. Indicating there were 6.4 times reduction in MIC for RIF-CHTNPs and 1.6 time reduction for CHTNPs comparing to MIC of antibiotic alone.