Improvement of antibacterial efficacy using antibiotic encapsulated silica-containing redox nanoparticles

Purpose: Improving solubility and antibacterial efficiency of cephalothin by using silica-containing redox nanoparticle (siRNP) as a system to encapsulate and deliver this hydrophobic antibiotic. Methods: siRNP was synthesized by assembling amphiphilic block copolymers possessing a reactive oxygen species scavenging nitroxide radical and drug absorptive silica moieties in a hydrophobic side chain. Cephalothin, a hydrophobic antibiotic, was encapsulated into siRNP (cephalothin@siRNP) by mixing and dialysis methods. Antibacterial activity of cephalothin@siRNP against Staphylococcus aureus (S. aureus) và Escherichia coli (E. coli) was evaluated by the agar diffusion method. Results: The average size of siRNP and cephalothin@siRNP was 43.83 nm and 50.15 nm, respectively. After encapsulation in siRNP, the solubility of cephalothin was improved compared to cephalothin in an aqueous solution. The result showed that in vitro antibacterial activities of cephalothin and cephalothin@siRNP had no statistical difference after 24 h incubation on agar plates on both S. aureus and E. coli. However, after an extended incubation time, regrowth of E. coli colonies in the inhibitory zone was found in cephalothin treated plate. Interestingly, E. coli regrowth was significantly reduced in plates treated with cephalothin@siRNP. Conclusion: In this study, siRNP successfully encapsulated cephalothin and enhanced the solubility of this drug. The antibacterial activity of cephalothin is prolonged when encapsulated in siRNP, which suppressed the reccurrence of E. coli colonies. Cephalothin@siRNP has the potential to inhibit antibiotic resistance.

Redox Nanoparticle Therapeutics for Acetaminophen-Induced Hepatotoxicity in Mice

The purpose of this study was to evaluate the hepatoprotective effect of an antioxidative nanoparticle (RNPN) recently developed against APAP-induced hepatotoxicity in mice. The effects of oral administration ofRNPNto APAP-treated mice were assessed for various biochemical liver function parameters: alanine transaminase (ALT) activity, aspartate transaminase (AST) activity, alkaline phosphatase (ALP) activity, prothrombin time, and serum albumin (ALB) level. The treatment effects were assessed in terms of free radical parameters: malondialdehyde (MDA) accumulation, glutathione peroxidase (GPx) activity, % inhibition of superoxide anion (O2-∙), and histopathological examination. TheN-acetylcysteine (NAC)-treated group exhibited an enhanced prothrombin time relative to the control group, whileRNPNdid not prolong prothrombin time. TheRNPN-treated animals exhibited lower levels of ALT, AST, and ALP, while increased ALB levels were measured in these animals compared to those in the other groups. TheRNPN-treated animals furthermore exhibited improved MDA levels, GPx activity, and % inhibition ofO2-∙, which relate to oxidative damage. Histological staining of liver tissues fromRNPN-treated animals did not reveal any microscopic changes relative to the other groups. The findings of this study suggest thatRNPNpossesses effective hepatoprotective properties and does not exhibit the notable adverse effects associated with NAC treatment.