Gold@mesoporous silica nanocarriers for the effective delivery of antibiotics and by-passing of β-lactam resistance

Abstract

Current antibiotics effectiveness relies on higher doses and administration frequency, which are responsible for the growth of antimicrobial resistance (AMR). AMR is one of the major threatening issues of the century with last-line antibiotics already failing. To overcome such problems associated with bacterial infections, nanoparticles combined with antibiotics emerged as a promising strategy. In this work, nanocarriers comprising of gold-silica core-shell mesoporous nanoparticles (Au@MNs) and silica mesoporous nanoparticles (MNs) were synthesized, loaded with amoxicillin (Amox) and ofloxacin and investigated regarding its antibacterial activity towards S. aureus, methicillin-resistant S. aureus (MRSA), E. coli and P. aeruginosa. Both nanocarriers showed a beneficial role in the effective delivery of amoxicillin against MRSA and the well-known β-lactam resistant P. aeruginosa. Reductions of 10-fold (Amox@MNs) and 20-fold (Amox@Au@MNs) in the amount of antibiotic to treat P. aeruginosa; and a reduction of 20-fold (Amox@MNs) towards MRSA allied to a full reversion of resistance, strongly supports the promising potential of these nanocarriers to tackle antibiotics resistance.

Silver and Gold Nanoparticles for Antimicrobial Purposes against Multi-Drug Resistance Bacteria

“…Both Au@MNs and silica mesoporous NPs presented an important role in the actual delivery of amoxicillin for P. aeruginosa and MRSA. Decreases of 10 times (Amox@MNs) and 20 times (Amox@Au@MNs) in the quantity of antibiotics to P. aeruginosa ; and a decrease of about 20 times (Amox@MNs) to MRSA was associated with a decline of resistance and finds these carriers capable of attacking AMR [ 145 ].…”

Advances in Nanostructures for Antimicrobial Therapy

“…Nanostructured Ag@SiO 2 –penicillin NPs containing 33.2 wt% of triangular Ag nanoplates and ca 2.8 wt% of grafted antibiotics showed a strong bactericidal effect against MSSA and MRSA bacteria and showed no cytotoxicity against A431 cell line [ 354 ]. Using Au–SiO 2 core-shell mesoporous NPs loaded with amoxicillin a 20-fold reduction of the amounts of antibiotic needed to treat β-lactam resistant P. aeruginosa and MRSA was observed, which in the case of MRSA corresponded to the reversion of resistance [ 355 ]. 80SiO 2 –15CaO–5P 2 O 5 mesoporous bioactive glass loaded with AgNPs (<5 nm; mole ratio in the range 1–10) exhibited the same in vitro antibacterial activity against MRSA with MIC of 10 mg/mL, independently of the loaded AgNPs amounts [ 356 ].…”

Progress in Mesoporous Silica Nanoparticles as Drug Delivery Agents for Cancer Treatment

“…The gold core was coated with MSNs shell via a sol–gel method of MSNs production. Interestingly, there were two morphologies reported for gold-MSNs core–shell structure, which are spherical and rod-like shape [ 91 , 92 ]. Marcelo and colleagues reported on the production of Janus nanoparticles consist of gold and MSNs.…”