Ampicillin-mediated functionalized gold nanoparticles against ampicillin-resistant bacteria: strategy, preparation and interaction studies

Abstract

Antibiotic resistance is a highly challenging concern of infectious diseases, and it requires a rational approach to overcome. Through this work, we have synthesized ampicillin-capped gold nanoparticles (Amp-Au NPs) and studied its interaction with bacterial cells. In this process of synthesis, the primary amine group of ampicillin acts as both reducing as well as capping agent. In addition to synthesized gold nanoparticles, the β-lactam ring remains free to interact with bacteria. This approach not only utilizes the maximum efficiency of nanoparticles and antibiotics towards ampicillin sensitive bacterial cells but also proves to be effective against ampicillin resistance bacteria. Our results illustrate that the optimized system of Amp-Au NPs was formulated by taking 1.25 mM ampicillin and 10−2 of gold ions concentration. UV–vis spectrum of gold nanoparticles and the presence of ampicillin were recorded at around 540 nm and 259 nm, respectively. Microscopic images indicate that particles are nearly spherical and are in size range between 25 and 50 nm. Moreover, formulated Amp-Au NPs show successful accumulation onto the surface of the bacterial cell as a result of which pores were formed into the bacterial membrane. The entry of nanoparticles into bacterial cells was validated through both atomic force microscopy and fluorescent microscopy. The adhesive properties of this coating material and its stability in various pH, i.e. pH 3, pH 7 and pH 10 conditions, could make them a good candidate in the prevention of biofilm formation. Amp-Au NPs show promising antimicrobial activity against ampicillin resistance Escherichia coli bacteria. Furthermore, antimicrobial studies indicate that the efficacy of Amp-Au NPs increased against both ampicillin sensitive and ampicillin resistance bacteria up to sixteen folds and four folds respectively.

Gold Nanoparticles: Can They Be the Next Magic Bullet for Multidrug-Resistant Bacteria?

“…Even at high concentrations of 4 μg/mL of ampicillin (70 μg/mL of AuNPs), the nanocomposite showed negligible cytotoxic effects making it an attractive option to be considered for future research and development. Ampicillin was used in another recent study by Chavan et al [91], where it served both as a reducing and capping agent to form ampicillin-capped gold nanoparticles (Amp-Au NPs). The synthesis process kept the β-lactam ring free to interact with bacteria.…”

“…According to the atomic force microscopy (AFM) and fluorescence imaging the nanoparticles accumulated on the bacterial cells, which led to the formation of pores into the bacterial membrane. These pores aided ampicillin to gain passive entry inside the bacterial cell and also sequestered Ampicillin was used in another recent study by Chavan et al [91], where it served both as a reducing and capping agent to form ampicillin-capped gold nanoparticles (Amp-Au NPs). The synthesis process kept the β-lactam ring free to interact with bacteria.…”

Antimicrobial Resistance and Inorganic Nanoparticles

“…The use of NPs together with antibiotics have been proved to act in a synergic way [ 124 , 165 ], reduce the dose used of antibiotic and NPs, achieve a high local concentration [ 166 ] or inclusive reverse the antibiotic resistance [ 165 , 167 ].…”

“…Chavan et al [ 166 ] synthesized 25 nm AuNPs coated with ampicillin (AuNPs-Amp) and evaluated their interaction with Escherichia coli bacterial cells. The results showed a successful accumulation of AuNPs-Amp on the surface of the bacterial cell, forming pores in the bacterial membrane.…”

Antibacterial Properties of Functionalized Gold Nanoparticles and Their Application in Oral Biology

“…In this synthesis process, the primary amine group of ampicillin acts as both a reducing agent and a capping agent. The nanogold not only maintains high antibacterial properties against ampicillin-sensitive bacteria but also proves to be effective against ampicillin-resistant bacteria [45]. Wang et al used a sulfur-gold (S-Au) bond to connect a cysteine-modified antimicrobial peptide and the broad-spectrum antimicrobial agent triclosan (TCS) to gold nanoparticles to prepare new types of antimicrobial peptide/triclosan double modified gold nanoparticles combined with antibacterial agents, improving the therapeutic effects and reducing the amount of antibacterial drugs, thereby decreasing the drugs' side effects.…”