Size and Shape Directed Novel Green Synthesis of Plasmonic Nanoparticles Using Bacterial Metabolites and Their Anticancer Effects

Abstract

The growing need for developing new synthesis methods of plasmonic nanoparticles (PNPs) stems from their various applications in nanotechnology. As a result, a variety of protocols have been developed for the synthesis of PNPs of different shapes, sizes, and compositions. Though widely practiced, the chemical synthesis of PNPs demands stringent control over the experimental conditions, often employs environmentally hazardous chemicals for surface stabilization, and is frequently energy-intensive. Additionally, chemically obtained PNPs require subsequent surface engineering steps for various optoelectronic and biomedicine applications to minimize the toxic effects and render them useful for targeted drug delivery, sensing, and imaging. Considering the pressing need to develop environmentally-friendly technology solutions, “greener” methods of nanoparticle synthesis are gaining importance. Here, we report on the biological synthesis of plasmonic nanoparticles using bacterial metabolites. A peptide-based siderophore pyoverdine and a blue-green pigment pyocyanin obtained from a marine strain of Pseudomonas aeruginosa rapidly produced plasmonic nanoparticles of gold and silver in an aqueous environment. The morphology of plasmonic nanoparticles could be modulated by tuning the concentration of these metabolites and the reaction time. The exposure of pyoverdine to chloroauric acid resulted in anisotropic gold nanoparticles. On the other hand, pyocyanin produced a highly monodispersed population of gold nanoparticles and anisotropic silver nanoparticles. Biologically obtained gold and silver nanoparticles retained pyoverdine and pyocyanin on the nanoparticle surface and were stable for an extended period of time. The biologically obtained gold and silver plasmonic nanoparticles displayed potent anticancer activities against metastatic lung cancer cells. Biogenic nanoparticles were rapidly internalized by cancer cells in high quantity to affect the cellular organization, and karyoplasmic ratio, indicating the potential of these nanoparticles for cancer nanomedicine.

Impedance nanobiosensor based on enzyme‐conjugated biosynthesized gold nanoparticles for the detection of Gram‐positive bacteria

“…As the particle size of the nanoparticles increases, the intensity of ruby-red color of the GNPs also enhances due to aggregation, and it turns purple (Figure 3c, inset). 2,34,43,46 The TEM micrograph shown in Figures S1 and S2 confirms the difference in size and shape of the BSGNPS using 0.5 and 1 mM precursor gold salt, respectively. Spherical BSGNPs were synthesized in the range of 10-28 nm using 0.5 mM gold salt as a precursor molecule (mean dia: 21.12 ± 4.68) (Figure S1).…”

“…Whereas, CFE of CEB3 and CUB12 could produce a purple suspension of GNPS, suggesting the synthesis of a larger size of GNPS compared to the others. 2,34,35 During the screening of bacterial cells for the synthesis of GNP, it was observed that the pale yellow color of the CFE of CEBS1 started to change to a red color first (within 4 h) in comparison to other CFE of different microbial stains. The UV spectra of CFE after incubation with auric chloride (1 mM) (Figure 1a) depicts SPR peak at 528 nm for CEBS1, which was lower than others.…”

“…4,7,10 The biosynthesized nanoparticles have potential pharmaceutical applications including delivery of targeted drugs or genes, tissue engineering, magnetic resonance imaging (MRI), DNA investigation, malignancy treatment, and detection of pathogens or proteins/biosensors. [2][3][4]11 Compared to other NPs, gold nanoparticle (GNP) is the most attractive choice to develop biosensing platforms for qualitative or quantitative detection of biomolecules due to their biocompatibility, inertness, optical, electrical, and chemical properties. 5,[12][13][14] GNPs are widely conjugated with biomolecules to improve the sensitivity of biosensor and provide a better microenvironment by increasing the surface area for electron transfer.…”

“…2 The size and shape of the NP may vary depending on the biomolecules present in the biological extracts, initial precursor concentration, reaction time, temperature, and pH of the media. 2 Green approaches for the generation of GNPS have great attention for their biocompatibility, excellent stability, good water solubility, and high conductivity, making them useful for analytical and biochemical research. 1,4,5,13 Biocompatible BSGNPS could be used to enhance specific enzyme activity, antimicrobial activity, drug delivery, and sensor development as it facilitates the electron transfer in nanoelectronics devices.…”

The two faces of pyocyanin - why and how to steer its production?

“…Moreover, Kohatsu et al (2020) showed that IC 50 of PYO and its halogenated form -chloropyocyanin, is much lower in human lung cancer and leukaemia cell lines than in normal fibroblasts. Patil et al (2022) applied P. aeruginosa metabolites, namely PYO, and pyoverdine, to synthesize gold and silver nanoparticles properties (Liu and Nizet 2009). From the engineering standpoint, the pivotal role of PYO in microbiologically induced corrosion (MIC) was recently recognized (Huang et al 2020).…”