Boosting Antimicrobial Activity of Ciprofloxacin by Functionalization of Mesoporous Silica Nanoparticles.

Blanca De Juan Mora,Andreia Forte,Luís Filipe,Miguel Santos,Rui Pedrosa,Sandra Gago,Manuela Ribeiro Carrott,Fernando Teodoro,Luís Branco,Celso Alves

doi:10.3390/pharmaceutics13020218

Abstract

Mesoporous silica nanoparticles (MSNs) are very promising nanomaterials for treating bacterial infections when combined with pharmaceutical drugs. Herein, we report the preparation of two nanomaterials based on the immobilization of ciprofloxacin in mesoporous silica nanoparticles, either as the counter-ion of the choline derivative cation (MSN-[Ch][Cip]) or via anchoring on the surface of amino-group modified MSNs via an amide bond (MSN-Cip). Both nanomaterials were characterized by TEM, FTIR and solution 1H NMR spectroscopies, elemental analysis, XRD and N2 adsorption at 77 K in order to provide the desired structures. No cytotoxicity from the prepared mesoporous nanoparticles on 3T3 murine fibroblasts was observed. The antimicrobial activity of the nanomaterials was determined against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Klebsiella pneumoniae) bacteria and the results were promising against S. aureus. In the case of B. subtilis, both nanomaterials exhibited higher antimicrobial activity than the precursor [Ch][Cip], and in the case of K. pneumoniae they exhibited higher activity than neutral ciprofloxacin.

Highlights

The treatment of infectious diseases caused by bacteria is frequently achievable by the use of antibiotics; these diseases are still one of the major causes of death worldwide
Mesoporous silica nanoparticles (MSNs) were prepared following the synthetic approach described by Bouchoucha et al [42], using Pluronic F127 as the non-ionic surfactant and triethanolamine as the co-inhibitor of particle growth
These nanomaterials were functionalized to achieve ciprofloxacin (Cip)-loaded MSNs either in ionic or neutral form, following the two different synthetic routes A and B illustrated in Scheme 1

Summary

Introduction

The treatment of infectious diseases caused by bacteria is frequently achievable by the use of antibiotics; these diseases are still one of the major causes of death worldwide. Such a failure in antibiotic treatment may be due to the rise of drug-resistant bacteria strains, as well as insufficient antibiotic activity or concentration at the site of infection. These problems are related to the reduced bioavailability, permeability and drug delivery of the drugs currently used.

Methods

Results

Conclusion