3 research outputs found
Qualitative Alterations of Bacterial Metabolome after Exposure to Metal Nanoparticles with Bactericidal Properties: A Comprehensive Workflow Based on <sup>1</sup>H NMR, UHPLC-HRMS, and Metabolic Databases
Metal
nanoparticles (NPs) have proven to be more toxic than bulk
analogues of the same chemical composition due to their unique physical
properties. The NPs, lately, have drawn the attention of researchers
because of their antibacterial and biocidal properties. In an effort
to shed light on the mechanism through which the bacteria elimination
is achieved and the metabolic changes they undergo, an untargeted
metabolomic fingerprint study was carried out on Gram-positive (<i>Staphylococcus aureus</i>) and Gram-negative (<i>Escherichia
coli</i>) bacteria species. The <sup>1</sup>H NMR spectroscopy,
in conjunction with high resolution mass-spectrometry (HRMS) and an
unsophisticated data processing workflow were implemented. The combined
NMR/HRMS data, supported by an open-access metabolomic database, proved
to be efficacious in the process of assigning a putative annotation
to a wide range of metabolite signals and is a useful tool to appraise
the metabolome alterations, as a consequence of bacterial response
to NPs. Interestingly, not all the NPs diminished the intracellular
metabolites; bacteria treated with iron NPs produced metabolites not
present in the nonexposed bacteria sample, implying the activation
of previously inactive metabolic pathways. In contrast, copper and
iron–copper NPs reduced the annotated metabolites, alluding
to the conclusion that the metabolic pathways (mainly alanine, aspartate,
and glutamate metabolism, beta-alanine metabolism, glutathione metabolism,
and arginine and proline metabolism) were hindered by the interactions
of NPs with the intracellular metabolites
Qualitative Alterations of Bacterial Metabolome after Exposure to Metal Nanoparticles with Bactericidal Properties: A Comprehensive Workflow Based on <sup>1</sup>H NMR, UHPLC-HRMS, and Metabolic Databases
Metal
nanoparticles (NPs) have proven to be more toxic than bulk
analogues of the same chemical composition due to their unique physical
properties. The NPs, lately, have drawn the attention of researchers
because of their antibacterial and biocidal properties. In an effort
to shed light on the mechanism through which the bacteria elimination
is achieved and the metabolic changes they undergo, an untargeted
metabolomic fingerprint study was carried out on Gram-positive (<i>Staphylococcus aureus</i>) and Gram-negative (<i>Escherichia
coli</i>) bacteria species. The <sup>1</sup>H NMR spectroscopy,
in conjunction with high resolution mass-spectrometry (HRMS) and an
unsophisticated data processing workflow were implemented. The combined
NMR/HRMS data, supported by an open-access metabolomic database, proved
to be efficacious in the process of assigning a putative annotation
to a wide range of metabolite signals and is a useful tool to appraise
the metabolome alterations, as a consequence of bacterial response
to NPs. Interestingly, not all the NPs diminished the intracellular
metabolites; bacteria treated with iron NPs produced metabolites not
present in the nonexposed bacteria sample, implying the activation
of previously inactive metabolic pathways. In contrast, copper and
iron–copper NPs reduced the annotated metabolites, alluding
to the conclusion that the metabolic pathways (mainly alanine, aspartate,
and glutamate metabolism, beta-alanine metabolism, glutathione metabolism,
and arginine and proline metabolism) were hindered by the interactions
of NPs with the intracellular metabolites
Carbonization of Human Fingernails: Toward the Sustainable Production of Multifunctional Nitrogen and Sulfur Codoped Carbon Nanodots with Highly Luminescent Probing and Cell Proliferative/Migration Properties
A simple
yet effective method is employed to prepare multifunctional fluorescent
carbon nanodots (CNDs) from human fingernails. The results demonstrate
that the CNDs have excellent optical properties and a quantum yield
of 81%, which is attributed to the intrinsic composition of the precursor
material itself. The CNDs are used to develop an ultrasensitive fluorescent
probe for the detection of hexavalent chromium (limit of detection:
0.3 nM) via a combined inner-filter and static mechanism. Moreover,
the toxicity of the CNDs over four epithelial cell lines is assessed.
A negligible toxicity is induced on the three of the cell lines, whereas
an increase in HEK-293 cell viability is demonstrated, granting cell
proliferation properties to the as-synthesized CNDs. According to
cell cycle analysis, cell proliferation is achieved by enhancing the
transition of cells from the S phase to the G2/M one. Interestingly,
CNDs are found to significantly promote cell migration, maybe because
of their free-radical scavenging ability, making the CNDs suitable
for wound healing applications. In addition, relevant experiments
have revealed the blood compatibility of the CNDs. Finally, the CNDs
were found suitable for cell imaging applications, and all of the
aforementioned merits make it possible for them to be used for extraordinary,
more advanced biological applications