Flumequine was nano-immobilized by self-assembly on iron oxide nanoparticles, called surface active maghemite nanoparticles (SAMNs). The binding process was studied and the resulting core-shell nanocarrier (SAMN@FLU) was structurally characterized evidencing a firmly immobilized organic canopy on which the fluorine atom of the antibiotic was exposed to the solvent. The antibiotic efficacy of the SAMN@FLU nanocarrier was tested on a fish pathogenic bacterium (Aeromonas veronii), a flumequine sensitive strain, in comparison to soluble flumequine and the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were assessed. Noteworthy, the MIC and MBC of soluble and nanoparticle bound drug were superimposable. Moreover, the interactions between SAMN@FLU nanocarrrier and microorganism were studied by transmission electron microscopy evidencing the ability of the complex to disrupt the bacterial wall. Finally, a preliminary in vivo test was provided using Daphnia magna as animal model. SAMN@FLU was able to protect the crustacean from the fatal consequences of a bacterial infection and showed no sign of toxicity. Thus, in contrast with the strength of the interaction, nano-immobilized FLU displayed a fully preserved antimicrobial activity suggesting the crucial role of fluorine in the drug mechanism of action. Besides the importance for potential applications in aquaculture, the present study contributes to the nascent field of nanoantibiotics.

• MeSH
• Aeromonas veronii účinky léků   MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• Daphnia účinky léků   mikrobiologie   MeSH
• fluorochinolony chemie   farmakologie   MeSH
• magnetické nanočástice chemie   MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Introduction of microfluidic mixing technique opens a new door for preparation of the liposomes and lipid-based nanoparticles by on-chip technologies that are applicable in a laboratory and industrial scale. This study demonstrates the role of phospholipid bilayer fragment as the key intermediate in the mechanism of liposome formation by microfluidic mixing in the channel with "herring-bone" geometry used with the instrument NanoAssemblr. The fluidity of the lipid bilayer expressed as fluorescence anisotropy of the probe N,N,N-Trimethyl-4-(6-phenyl-1,3,5-hexatrien-1-yl) was found to be the basic parameter affecting the final size of formed liposomes prepared by microfluidic mixing of an ethanol solution of lipids and water phase. Both saturated and unsaturated lipids together with various content of cholesterol were used for liposome preparation and it was demonstrated, that an increase in fluidity results in a decrease of liposome size as analyzed by DLS. Gadolinium chelating lipids were used to visualize the fine structure of liposomes and bilayer fragments by CryoTEM. Experimental data and theoretical calculations are in good accordance with the theory of lipid disc micelle vesiculation.

• MeSH
• biokompatibilní materiály metabolismus   MeSH
• cholestyraminová pryskyřice metabolismus   MeSH
• fluidita membrány * MeSH
• fluorescenční polarizace MeSH
• laboratoř na čipu MeSH
• liposomy chemická syntéza   MeSH
• mikrofluidika přístrojové vybavení   metody   MeSH
• nanostruktury * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH