The Application Of Nanomaterials For Anti-Bacterial Based On Antibiotic

The spread of bacterial infection menace the health of mankind seriously, todetection and inhibit the propagation of bacterial by antibacterial materials is animportant way to improve the health level of people. Vancomycin has specific targets andgood inhibition for gram positive bacteria. However, the vancomycin has strong ear andkidney toxicity，So in this article, we use vancomycin-modified mesoporous silicananoparticles for selective recognition and killing of pathogenic gram-positive bacteriaover macrophage-like cells and core-shell supramolecular gelatin nanoparticles foradaptive and “on-demand” antibiotics delivery.In this work, we demonstrated the vancomycin-modified mesoporous silicananoparticles (MSNs Van) for efficiently targeting and killing gram-positive bacteriaover macrophage-like cells. Owing to the specific hydrogen bonding interactions ofvancomycin towards the terminal D-alanyl-D-alanine moieties of gram-positive bacteria,the MSNs Van exhibited enhanced recognition for gram-positive bacteria due to themultivalent hydrogen binding effect. Furthermore, the fluorescent molecules (FITC)were covalently decorated inside of mesopores of MSNs for tracking and visualizing theMSNs Van during the detection/treatment processes. Upon incubation of FITCdecorated MSNs with bacteria (i.e., S. aureus and E. coli as gram-positive andgram-negative bacteria, respectively) or macrophage-like cells (Raw264.7), thefluorescence signals in S. aureus were2~4times higher than that in E. coli and nodetectable fluorescence signals were observed in Raw264.7cells under the samecondition. Finally, the MSNs Van showed unambiguous antibacterial efficacy withoutdecrease in cell viability of macrophage-like cells. This new strategy opens a new doorfor specific detection and treatment of pathogenic bacteria with minimized side effect.The solution strategies of avoiding antibiotic resistance are emerging, such as thedevelopment of antibiotic replacements and intelligent antibiotic delivery system. In consideration of the widespread use of antibiotic in clinic, the intelligent antibioticdelivery systems call for emergency. Among them, the “on demand” delivery systemswith immune evading capability realizing site-specific release and high local drugconcentration can dramatically reduce the generation of antibiotic-resistance and increasethe life time of newly developed antibiotics. Here we present antibiotic delivery system(Van SGNPs@RBC) based on core-shell supramolecular gelatin nanoparticles (SGNPs)for adaptive and "on-demand" antibiotic delivery. The core composed of cross-linkedSGNPs allows for bacterial infection-microenvironment responsive release of antibiotics.The shell coated with uniformed red blood cell membranes executes the function ofdisguise for reducing the clearance by immune system during the antibiotic delivery, aswell as absorbs the bacteria exotoxin for relieving symptoms caused by bacterialinfection. This approach demonstrates an intelligent and biomimetic antibiotic deliverysystem for treatment of bacterial infection with minimum dose of antibiotics.