Mouse Anti-Vancomycin monoclonal antibody, clone 30

Mesoporous silica nanoparticles (MSNs) carrying gatekeepers that are stimuli-responsive are widely investigated for the controlled delivery of drug at target sites. In this study, thioketal (TK) functionalized methoxy poly(ethylene glycol) (mPEG-TK) as ROS-responsive gatekeeper is used to modify MSNs and leads to a reactive oxygen species (ROS)-responsive delivery for antibacterial drug. Vancomycin (Van) was taken as the antibacterial drug and then physically encapsulated into the surface amino functionalized MSNs (N-MSNs). Subsequently, mPEG-TK was surface immobilized. Van loaded N-MSNs with surface modification of mPEG-TK (Van-mPEG-TK-MSNs) presented approximately 21% release of Van in a physiological environment in 36 h. With H2O2 increasing in the medium, the release rate of Van from Van-mPEG-TK-MSNs was significantly up-regulated following gatekeepers' disintegration. When Van-mPEG-TK-MSNs was applied in vivo, the infected site was fully cleared after 14 days and the tissue was free of infection. On the whole, the mentioned results suggested that Van-mPEG-TK-MSNs could act as a potential antimicrobial. This study can broaden MSNs' applications and advance the development of novel antibacterial agents. (c) 2020 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

In this study, we used electrospun polycaprolactone (PCL) or a mixture of PCL and gelatin (Gel) in a mixed acidic solvent to develop antimicrobial electrospun nanofibers. Carboxyl-modified mesoporous silica nanoparticles (CMSNs) or CMSNs loaded with antibiotic drugs polymyxin B and vancomycin (CMSNs/ABs) were mixed with the electrospinning solution in concentrations of 1%, 2.5% and 5%. The nanofibers diameter measured between 122 and138 nm. Higher concentrations of gelatin or CMSNs increased hydrophilicity and degradability of the nanofibers. CMSNs enhanced nanofibers mechanical strength. PCL/Gel nanofibers incorporated with CMSNs/ABs (2.5% and 5%) showed high antibacterial efficiency against Pseudomonas aeruginosa and Staphylococcus aureus. Also bacterial cell adhesion decreased when 2.5% and 5% of CMSNs/ABs were incorporated in PCL/Gel mats. MTT and hemolysis assays indicated excellent biocompatibility of all types of electrospun nanofibers. This study confirms that a proper mixture of PCL, gelatin and CMSNs loaded with two antibiotics could offer antimicrobial activities with high biocompatibility and biodegradability properties. [GRAPHICS] .