Abstract
In this study, a spherical silica nanoparticle was explored as a gatifloxacin carrier synthesized by the chemical precipitation method. It was found that there was no new chemical bond formation during the loading process between gatifloxacin and silica, which implies that the binding was driven by physical interaction. In addition, the drug loading and encapsulation efficiency could be improved by appropriately increasing nano-silica content in the loading process. Meanwhile, the release rate of gatifloxacin after loading nano-silica was also improved, suggesting the successful design of a controlled-release delivery composite. The silica nanocarrier could significantly improve the antibacterial performance of Escherichia coli by 2.1 times, which was higher than the pure gatifloxacin. The 24 h bacteriostatic rate was higher than that of a simple mixture of silica nanoparticles and gatifloxacin. Strong reactive oxygen species (ROS) in GAT-SiO2 NPs suggests that ROS might be associated with bactericidal activity. The synergy between the physicochemical effect and ROS production of this material is proposed as the mechanism of its antibacterial activity, which can also be confirmed by the cell membrane damage observed under electron microscopy and DNA damage experiments. Collectively, our finding indicates that nano-silica microspheres could serve as a promising carrier for the sustained release of gatifloxacin, thereby providing a new carrier design scheme for the improvement of the antibacterial effect.
Highlights
Gatifloxacin (GAT) is a new type of fluoroquinolone antibiotics, which mainly inhibits DNA topoisomerase and gyrase of bacteria to achieve an antibacterial effect
Scanning electron microscopy and transmission electron microscopy show that the nano-silica are evenly spherical solid with a smooth surface (Figures 1A,C), and the morphology had no obvious change after loading gatifloxacin (Figures 1B,D)
The solution potential of nano-silica-loaded gatifloxacin was increased to −17.62 mV, which indicated gatifloxacin stability could be improved by nano-silica, and the binding of nano-silica and gatifloxacin could not be driven by the electrostatic interactions but probably by intermolecular forces (Zhang et al, 2019)
Summary
Gatifloxacin (GAT) is a new type of fluoroquinolone antibiotics, which mainly inhibits DNA topoisomerase and gyrase of bacteria to achieve an antibacterial effect. It has the advantages of broadspectrum antibacterial, low phototoxicity, and good tissue operation (Takei et al, 1998). Nano-silica has attracted wide attention due to its environmentally friendly and stable properties in various chemical environments In recent years, it has been considered one of the most promising drug delivery systems and widely used in pharmaceutical preparations. The findings of our study have provided valuable insights into the real application of nano-silica as a drug carrier
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
