title: Continuous release of gentamicin from gold nanocarriers.
abstract: Antibiotics are still the most effective agents used to fight bacterial infections. Antibiotics are quickly metabolised or excreted from the human body, thus they need to be frequently administered (a few times a day) and their half life is usually an important factor in the therapeutic choice. In order to render the administration less frequent, antibiotic release from a carrier can be employed. In this work we covalently bound gentamicin to gold nanoparticles capped with cysteine or glutathione as gold nanoparticles are biologically safe. The conjugates exhibited antimicrobial activity against bothS. aureusand MRSA at concentrations as low as 0.1 mg NP per ml consistent with an antibiotic load of 1-2% w/w as determined through TGA. No antimicrobial activity was exhibited by the unconjugated nanoparticles. The release of gentamicin from the conjugates was monitor in buffer solutions at pH = 7 and the antibiotic concentration continued to increase over two days. This work demonstrates that gold nanoparticles can be employed as antibiotic carriers providing a continuous release of antibiotic over a few days. Glutathione appeared to be a better coupling agent than cysteine allowing a higher load of gentamicin resulting in lower inhibitory concentrations of the conjugates.
authors.affiliation: School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, CF10 3NB, UK. Email: prokopovichp@cardiff.ac.uk ; ; Tel: +44 (0)29 208 75820 ; Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, USA.
authors.forename: Stefano
authors.initials: S
authors.lastname: Perni
authors.affiliation: School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, CF10 3NB, UK. Email: prokopovichp@cardiff.ac.uk ; ; Tel: +44 (0)29 208 75820 ; Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, USA.
authors.forename: Polina
authors.initials: P
authors.lastname: Prokopovich