The Influence of Different Forms of Silver on Selected Pathogenic Bacteria

Abstract

The application of silver nanoparticles as an antibacterial agent is becoming more common. Unfortunately, their effect on microorganisms is still not fully understood. Therefore, this paper attempts to investigate the influence of silver ions, biologically synthesized silver nanoparticles and nanoparticles functionalized with antibiotics on molecular bacteria profiles. The initial stage of research was aimed at the mechanism determination involved in antibiotics sorption onto nanoparticles’ surface. For this purpose, the kinetics study was performed. Next, the functionalized formulations were characterized by Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS) and a zeta potential study. The results reveal that functionalization is a complex process, but does not significantly affect the stability of biocolloids. Furthermore, the antimicrobial assays, in most cases, have shown no increases in antibacterial activity after nanoparticle functionalization, which suggests that the functionalization process does not always generate the improved antimicrobial effect. Finally, the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) technique was employed to characterize the changes in the molecular profile of bacteria treated with various antibacterial agents. The recorded spectra proved many differences in bacterial lipids and proteins profiles compared to untreated cells. In addition, the statistical analysis of recorded spectra revealed the strain-dependent nature of stress factors on the molecular profile of microorganisms.

Antibacterial Therapy by Ag+ Ions Complexed with Titan Yellow/Congo Red and Albumin during Anticancer Therapy of Urinary Bladder Cancer

“…Microbiological analyzes showing the effect of silver in various forms have been previously carried out on different bacterial strains [ 60 ]. Nevertheless, the MIC and MBC values after treatment with TY-Ag or BSA-TY-Ag in E. coli and S. aureus have been presented here for the first time.…”

Molecular Interactions between Saliva and Dental Composites Resins: A Way Forward

“…CHX is also able to traverse by passive diffusion the bacterial cell membrane, and to induce cytosolic lesions, leading to apoptosis [ 11 , 12 ]. Other studies outlined the special antimicrobial activity of the silver ions, which can be used effectively to prevent infections [ 15 , 16 ]. We should mention here the strategy of loading this Ag particles into the filler of the composite, rather than to the resin matrix [ 13 ].…”

The Study on Molecular Profile Changes of Pathogens via Zinc Nanocomposites Immobilization Approach

“…For this step, based on the MIC value, the optimal concentration (25% of the MIC value) was chosen. The antibacterial doses were selected experimentally and based on our previous studies with silver (bio)nanoparticles [18] to obtain the sufficient amount of the bacterial cells for the analysis by the MALDI technique. Figure 8 depicts the growth kinetics curves of E. coli, S. epidermidis and K. pneumoniae treated with AMP, TET, Zn 2+ , ZnONPs, ZnONPs/AMP and ZnONPs/TET, and non-treated cells that served as a control.…”

“…The obtained cultures were transferred to a new sterile falcon tube, centrifuged (10 min, 10 • C, 4000 rpm) and obtained pellets were washed twice with sterile water. Then, the protein and lipid extractions were performed according to Buszewski et al [18].…”

“…Due to the many possible methods of zinc oxide nanoparticles synthesis (e.g., sol-gel, co-precipitation, hydrothermal, biological) and the control of the synthesis process, it is possible to obtain nanoparticles with various properties (morphology, shape, size) and different antibacterial potentials [1,9]. Interestingly, our previous works show that the combination of nanoparticles with conventional pharmaceutical agents (e.g., antibiotics) might be a great opportunity for commonly used treatments [16][17][18]. It leads to a synergistic action-a phenomenon occurring as a result of combining two different factors in order to increase their individual activity [19].…”