Silica-Coated Magnetic Nanoparticles for Vancomycin Conjugation

Abstract

Drug resistance is a global health challenge with thousands of deaths annually caused by bacterial multidrug resistance (MDR). Efforts to develop new antibacterial molecules do not meet the mounting needs imposed by the evolution of MDR. An alternative approach to overcome this challenge is developing targeted formulations that can enhance the therapeutic efficiency and limit side effects. In this aspect, vancomycin is a potent antibacterial agent that has inherent bacterial targeting properties by binding to the D-Ala-D-Ala moiety of the bacterial peptidoglycan. However, the use of vancomycin is associated with serious side effects that limit its clinical use. Herein, we report the development of vancomycin-conjugated magnetic nanoparticles using a simple conjugation method for targeted antibacterial activity. The nanoparticles were synthesized using a multistep process that starts by coating the nanoparticles with a silica layer, followed by binding an amide linker and then binding the vancomycin glycopeptide. The developed vancomycin-conjugated magnetic nanoparticles were observed to exhibit a spherical morphology and a particle size of 16.3 ± 2.6 nm, with a silica coating thickness of 5 nm and a total coating thickness of 8 nm. The vancomycin conjugation efficiency on the nanoparticles was measured spectrophotometrically to be 25.1%. Additionally, the developed formulation retained the magnetic activity of the nanoparticles, where it showed a saturation magnetization value of 51 emu/g, compared to 60 emu/g for bare magnetic nanoparticles. The in vitro cell biocompatibility demonstrated improved safety where vancomycin-conjugated nanoparticles showed IC 50 of 183.43 μg/mL, compared to a much lower value of 54.11 μg/mL for free vancomycin. While the antibacterial studies showed a comparable activity of the developed formulation, the minimum inhibitory concentration was 25 μg/mL, compared to 20 μg/mL for free vancomycin. Accordingly, the reported formulation can be used as a platform for the targeted and efficient delivery of other drugs.

Synergistic Antimicrobial Activity of Magnetite and Vancomycin-Loaded Mesoporous Silica Embedded in Alginate Films

“…The alginate films enriched with MCM-41@Van and magnetic nanoparticles functionalized with malic acid had better antimicrobial activity, especially against E. faecalis and S. aureus , confirming the synergic effect between bioactive compounds [ 53 , 54 , 55 ].…”

“…Thus, after a burst release, most probably caused by the available drug on the surface, the drug from the pores is also released and maintains a proper concentration of Van. Therefore, these systems have better antimicrobial activity [ 45 , 53 , 59 , 60 ]. Otherwise, the bioactive compounds from AGSi and AGSiM films showed the highest sensitivity against C. albicans .…”

Biosynthesis of Zinc Nanoparticles From Actinobacterium Streptomyces Species and Their Biological Potential

“…A microtiter-dilution resazurin test was used to assess the antibacterial efficacy of NP alone and in conjunction with antibiotics against multidrug-resistant (MDR) bacteria. It was found to have a synergistic effect [ 24 , 25 ]. ZnONPs have remarkable and incredible properties.…”

Designing magnetic catalysts based on gold nanoparticles supported by ethylenediamine tetraacetic acid functionalized amino‐modified poly(N‐isopropyl acrylamide) for reduction of nitro compounds in water

“…This drop in saturation might result from the surface coating and functionalization of Fe 3 O 4 MNPs with polymer chains and a decrease in iron oxide content in the unit weight sample. 46 The most significant magnetization decrease occurred in polymer modification with the amino group. However, this catalyst was still easily separated and recovered with a magnet.…”