Cefotaxime Mediated Synthesis of Gold Nanoparticles: Characterization and Antibacterial Activity.

Turki Al Hagbani,Marwa H Abdallah,Khalid Mehmood,Afrasim Moin,Amr Selim Abu Lila,Syed Mohd Danish Rizvi,Zeeshan Rafi,El-Sayed Khafagy,Farhan Alshammari,Talib Hussain,Mohamed Rahamathulla

doi:10.3390/polym14040771

Abstract

Cefotaxime (CTX) is a third-generation cephalosporin antibiotic with broad-spectrum activity against Gram negative and Gram positive bacteria. However, like other third-generation cephalosporin antibiotics, its efficacy is declining due to the increased prevalence of multidrug-resistant (MDR) pathogens. Recent advances in nanotechnology have been projected as a practical approach to combat MDR microorganisms. Therefore, in the current study, gold nanoparticles (AuNPs) were prepared using cefotaxime sodium, which acted as a reducing and capping agent, besides having well-established antibacterial activity. The synthesized cefotaxime-loaded gold nanoparticles (C-AuNPs) were characterized by UV-Visible spectroscopy, FTIR, TEM and DLS. In addition, the in vitro antibacterial activity of C-AuNPs was assessed against both Gram-positive and Gram-negative bacteria. UV-Visible spectroscopy verified the formation of C-AuNPs, while TEM and DLS verified their nano-size. In addition, CTX loading onto AuNPs was confirmed by FTIR. Furthermore, the colloidal stability of the synthesized C-AuNPs was ascribed to the higher net negative surface charge of C-AuNPs. Most importantly, the synthesized C-AuNPs showed superior antibacterial activity and lower minimum inhibitory concentration (MIC) values against Gram-negative (Escherichia coli, Klebsiella oxytoca, Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria, compared with pure CTX. Collectively, CTX was successfully adopted, as reducing and capping agent, to synthesize stable, nano-sized spherical C-AuNPs. Furthermore, loading CTX onto AuNPs could efficiently restore and/or boost the antibacterial activity of CTX against resistant Gram-negative and Gram-positive bacteria.

Highlights

Cefotaxime sodium (CTX), a cephalosporin sodium salt having [2-(2-amino-1,3-thiazol-4-yl)-2-(methoxyimino)acetyl]amino and acetoxymethyl side groups, is a powerful -lactamase third-generation antibiotic
Our results indicated the formation of CTX-loaded AuNPs (C-AuNPs) using a facile one-pot synthesis method, in which CTX efficiently acted as a reducing/capping agent (Figure 1)
This method nullified the use of an external chemical or biomolecule as reducing/capping agents and avoided the existence of residual contaminations that might interfere with the antibacterial results

Summary

Introduction

Cefotaxime sodium (CTX), a cephalosporin sodium salt having [2-(2-amino-1,3-thiazol-4-yl)-2-(methoxyimino)acetyl]amino and acetoxymethyl side groups, is a powerful -lactamase third-generation antibiotic. Bacteria have reportedly acquired a novel form of β-lactamase enzyme that results in conferring resistance to antibiotics containing β-lactam ring such as cefotaxime [4,5,6]. Changing the structure of antibiotics’ β-lactam moiety [7,8] and synthesizing new antibiotics with higher potencies [9] are two important strategies used for overcoming bacterial resistance. These approaches are time consuming and are frequently not economically viable [10]

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Conclusion