Morphology Of Gold Nanoparticles Research Articles

Nanogold Foundry Involving High‐Shear‐Mediated Photocontact Electrification in Water

Controlling the size and morphology of gold nanoparticles occurs in the absence of added reducing agents or other excipients such as surfactants, on UV irradiation (λ 254 nm) of aqueous auric acid (H[AuCl4]) in a thin film of liquid in a vortex fluidic device (VFD) within a rapidly rotating tilted quartz tube. This involves contact electrification (CE), which occurs at the solid−liquid interface with the oxidation of water photoinduced, forming the hydroxyl radical, OH•. In air, the redox couple is reduction of 3O2 to the superoxide radical anion, O2−•, which then reduces Au3+ to elemental gold, as does other reactive oxygen species present, competing with CE reduction of Au3+. The resulting nanogold structures effectively mold the different high‐shear topological fluid flows in the VFD, being isolated as ultrathin 2D sheets, prisms, hierarchical structures comprising nanoparticles embedded within these sheets, and rosette and tubular structures, depending on the VFD processing parameters and the concentration of auric acid. Processing under a nitrogen atmosphere while UV irradiated affords mainly 2D gold through the above reduction of Au3+. The findings establish a paradigm for VFD processing in water involving photo‐CE, generating hydrogen peroxide and hydrogen gas with the surfaces of the gold nanoparticles pristine.

Insights into the role of ionic surfactants on the morphology of gold and gold@silver nanoparticles

Cyanidin-3, 5-di-O-glycoside (anthocyanin) was extracted from the red rose flower petals in an aqueous media. Anthocyanin was used as reductant to the preparation of gold nanoparticles with cationic and anionic surfactants. UV–visible absorption spectroscope, transmission electron microscope, scanning electron microscope, and energy dispersive X-ray spectroscope were employed to determine absorption bands of anthocyanin, surface Plasmon resonance (SPR) band, and morphology of the gold and gold@silver nanoparticles. Anthocyanin exhibited two absorption peaks at 284 and 518 nm, and one shoulder at 328 nm in the UV–visible spectrum. The intensity of these peaks decreases with time after the addition of HAuCl4. The color and the position of SPR band of gold nanoparticles depend on the concentration of gold salt with and without cetyltrimethylammonium bromide (CTAB), and sodium dodecyl sulfate (SDS). The anionic and cationic head groups of SDS and CTAB micelles have significant impact of the morphology of gold nanoparticles. Seedless co-reduction method was used for the synthesis of gold@silver nanoparticles. TEM images clearly indicate the formation of bimetallic gold@silver core-shell nanoparticles. The antioxidant power of AuNPs and gold@silver nanoparticles were tested in terms of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity as a function of different concentrations of nanoparticles.

Biosynthesis of Gold Nanoparticles Using Aqueous Extract of Paramignya trimera Roots and Its Anticancer Activity

Developing environment-friendly processes for metal nanoparticle synthesis without using toxic chemical is very necessary to meet the demand for biological and medical applications. In this work, biosynthesis of gold nanoparticles (AuNPs) using aqueous extract of Paramignya trimera roots as the reducing and stability agents was carried out. The formation of gold nanoparticles was confirmed by the presence of an absorption peak at 550 nm using UV–Visible spectrophotometry. The size and morphology of gold nanoparticles was monitored by Field emission scanning electron microscopy (FE-SEM) and High resolution transmission electron microscopy (HR-TEM). Analysis of these particles showed the synthesized AuNPs were spherical in shape, with the particle size range of 10 nm–15 nm. The element gold and the crystalline nature of AuNPs were finalized using Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) spectrometer, respectively. Fourier transform infrared (FTIR) spectroscopy revealed possible involvement of reductive groups on the surfaces of nanoparticles. The synthesized AuNPs are evaluated for its activity against MCF-7, HepG2, KB, LU-1 and MKN7 cancer cell lines with inhibition concentration 50% (IC50) of 2.01, 7.60, 3.89, 3.99 and 3.53 ppm respectively after 72 hours of treatment.

Gold nanoparticle morphology adjusted as high-performance catalyses in supergiant dispersant

The deliberate engineering of environmentally benign and sustainable catalytic processes involving anisotropic gold nanoparticles (AuNPs) presents a formidable challenge. In this investigation, a novel green synthesis of anisotropic AuNPs is achieved by reducing an Au precursor through the oxidation of anionic superdispersant mega-polysaccharides known as sacran, as confirmed by XPS techniques. The reduction potential influences the resulting Au shapes, with differences observed at higher sacran concentrations or higher reduction potentials. The use of monodispersed seeds, along with the assistance of iodide anions, induces high uniform anisotropic growth. Under optimized conditions, the occupancy of triangular AuNPs (AuNTs) with uniform sizes and morphologies reached an impressive ∼92% area ratio. Additionally, an alternative synthesis condition leads to the formation of decahedral AuNPs (AuNDs). Notably, the AuNTs exhibit exceptional catalytic performance towards 4-nitrophenol (4-NP) with a specific rate constant (k) of 2.90×10³ s⁻¹g⁻¹, which is 3.4 times higher than that of most reported AuNPs under conventional capping agents. The catalytic activity remains satisfactory after multiple reaction cycles, highlighting the sustainability of AuNTs within the superdispersant mega-saccharides medium. Furthermore, the AuNTs catalyst demonstrates both an excellent conversion rate and selectivity for the catalytic reduction of a series of chloro-substituted nitroarenes.

Tuning chiral morphology of gold nanoparticles with reversed chiral signals by adjusting the reaction temperature of the seed-mediated growth process

Reaction temperature was found to reverse the chiral modes of the gold nanoparticles (AuNPs) prepared through the seed-mediated and chiral ligand-directed growth method.

Raman Spectroscopy Analysis of the Morphology of Gold Nanoparticles Produced by Laser Ablation in Aqueous Proteinogenic Amino Acid for the Detection of Mercury in Water

Raman Spectroscopy Analysis of the Morphology of Gold Nanoparticles Produced by Laser Ablation in Aqueous Proteinogenic Amino Acid for the Detection of Mercury in Water

Tuning the plasmon resonance of Au-Ag core-shell nanoparticles: The influence on the visible light emission for inorganic fluorophores application

In this study, the gold and gold-silver (Au-Ag) core-shell nanoparticles were synthesized via chemical reduction method at different types and quantities of precursor materials. Initially, the gold nanoparticles were prepared with different reducing agents (i.e., sodium borohydride, sodium citrate, and ascorbic acid) and their composites. The optical absorbance, morphology, and size distribution of gold nanoparticles were analyzed to observe the best deposition conditions, used for the Au-Ag core-shell synthesis. Then, the Au-Ag core-shell nanoparticles were grown at four different quantities (i.e., 175 µL, 200 µL, 225 µL, and 250 µL) of silver nitrate precursor to study their effects on the fluorescence property. Optical absorbance, transmission electron microscopy, and laser scanning confocal microscopy were used to characterize the as-synthesized Au-Ag core-shell nanoparticles. From the results of optical absorbance, a single peak is seen for gold nanoparticles while two peaks (major and minor peaks) are observed for Au-Ag core-shell nanoparticles. The sizes of gold and core-shell particles observed from TEM measurement are less than 10 nm, which is typically used in fluorescence applications. The CoSh-2 sample showed a better fluorescence property compared to other core-shell samples. With a rise in exposure time in a laser with a specific wavelength of 405 nm, the intensity of fluorescence declined more for the filter having shorter wavelengths than larger wavelengths. Analyzing these results can be useful to understand the perspective applications of Au-Ag core-shell nanoparticles like synthetic fluorophores application.

Two co-propagating trapping laser beams control optical swarming morphology of gold nanoparticles

Optical trapping of gold nanoparticles at the glass/solution interface gives a single swarming assembly upon irradiating a tightly focused 1064 nm laser. The swarming morphology shows dumbbell-shaped and circular assembling for linearly and circularly polarized laser beams, respectively. Two co-propagating laser beams split from one trapping laser create new morphology, depending on laser polarization and the separation distance of the beams. When the distance is short, the morphology is not much changed. As the distance increased, new morphology appeared where the nanoparticles migrated. The results are well interpreted from the viewpoint of constructive and destructive interference between two beams.

Atomic Scale Observation of the Structural Dynamics of Supported Gold Nanocatalysts under 1,3‐Butadiene byin situEnvironmental Transmission Electron Microscopy

AbstractSupported gold catalysts have been reported to exhibit exceptional selectivity towards the desirable product, an alkene, in chemoselective hydrogenation of highly unsaturated alkynes and alkadienes. However, insights on the interactions between the gold nanoparticles and the 1,3‐butadiene adsorbates are lacking. In this work, using atomic scalein situETEM with the support of DFT‐based calculations, the reactivity of TiO2supported gold nanoparticles below 7 nm towards 1,3‐butadiene is investigated by monitoring their structure and dynamics under 105 Pa of 0.46 % C4H6/He during cooling at 300 °C and 200 °C. For sizes larger than 5 nm, the initial truncated octahedron morphology of gold nanoparticles is found to evolve towards a rounded morphology, with the growth of more open (110) surfaces and higher index facets at the expense of the initially present (100) and (111) facets, reflecting the adsorption of butadiene on low coordination sites at 300 °C. The morphology changes are shown to be accompanied by nucleation and glide of dislocations. At 200 °C, 1,3‐butadiene adsorption is shown to predominateon (111) facets, with the nanoparticles reverting to a faceted morphology while maintaining their fcc structure. For smaller particle size, Au fcc structure is also maintained under 1,3‐butadiene.

Unravelling optical properties and morphology of plasmonic gold nanoparticles synthesized via a novel green route

Unravelling optical properties and morphology of plasmonic gold nanoparticles synthesized via a novel green route

Физико-химические свойства наночастиц золота в рудах и катализаторах

Introduction. At present, in the instrumental study of the mineral forms of finding gold in geogenic and technogenic ores, more and more attention has been paid to free gold, with a size of several nanometers. Such gold has been found in almost all types of its geogenic ores: starting with deposits of primary sulfide ores and ending with various gold-bearing placers. A similar situation is observed with technogenic gold-bearing ores accumulated in numerous dumps and tailings. At the same time, with the increase in research on nanogold, not only its fundamental, but also practical importance grows, because. in theoretical and applied research, more and more of its actual physical and chemical properties and previously unknown phenomena and effects accompanying them are discovered and clarified. Research methods and materials. An important aspect is the instrumental study of the geometry of various forms of nanogold occurrence in natural (geogenic) and technogenic ores and minerals. The instrumental and analytical part of our research was based on the visualization of nanoparticles obtained from the Nanjing Research Institute of the Chemical Industry under Sinopec (PRC), carried out on a JEOL 2010F microscope. Research results. The studied gold nanoparticles were presented in the form: • spherical fullerene-like monoparticles; • fullerene-like gold cells, consisting of a different number (from 13 to 20 clusters) of gold nanoparticles; • self-organized «fractal» dendrites; • rather complex composites with the participation of nanogold; • various aggregates of nanoparticles, etc. The concentrations of gold nanoparticles vary significantly from one deposit to another and between individual ore facies (even within the same deposit). Discussion of the obtained results. It was found that nanogold can be contained in arsenopyrites in 2 main forms: a) as a structurally bound solid solution (Au + 1) located in the lattice of this mineral; b) in separate mineral inclusions of submicron size or nanoparticles. Gold nanoparticles (5-10 nm in size) detected in arsenopyrite in concentrations up to 4% mass fraction are sufficiently representative to account for their amount in gold-bearing ores. A gold nanoparticle with a size of 3 nm usually has an average coordination number CN = 9.5, similar nanoparticles with a size of 1 nm have an average CN = 6, and nanoparticles with a size of 0.5–1 nm have an average CN = 3.6. Conclusion. To date, a nanoparticle catalyst has been developed in which gold clusters are attached to metal oxides that are semiconductors. At the same time, their number is very limited and includes only Fe2O3, TiO2, CeO2, and MgO compounds, which can be used not only in the form of nanoparticles, but also nanofilms. Such an innovative nanocatalyst ensures the efficient flow of a number of oxidative and other processes with hydrocarbons at normal temperatures, which is difficult to achieve by other methods. Findings. The article presents the results of studies of the physicochemical properties of gold nanoparticles installed in ores and catalysts. The morphology of gold nanoparticles has been established. The character of gold speciation in various sulfides is determined. The presence of gold nanoparticles in ores and rocks in the state of colloids has been confirmed. The catalytic activity of nanoparticles of various shapes and chemical states was revealed, depending on the values of the ambient temperature. The results of the research can be useful in the enrichment of gold-bearing ores of upland deposits.

Interaction of Colloidal Gold Nanoparticles with Urine and Saliva Biofluids: An Exploratory Study.

The use of gold nanoparticles for drug delivery, photothermal or photodynamic therapy, and biosensing enhances the demand for knowledge about the protein corona formed on the surface of nanoparticles. In this study, gold nanospheres (AuNSs), gold nanorods (AuNRs), and gold nanoflowers (AuNFs) were incubated with saliva or urine. After the interaction, the surface of gold nanoparticles was investigated using UV-VIS spectroscopy, zeta potential, and dynamic light scattering. The shifting of the localized surface plasmon resonance (LSPR) band, the increase in hydrodynamic diameter, and the changes in the surface charge of nanoparticles indicated the presence of biomolecules on the surface of AuNSs, AuNRs, and AuNFs. The incubation of AuNFs with saliva led to nanoparticle aggregation and minimal protein adsorption. AuNSs and AuNRs incubated in saliva were analyzed through liquid chromatography with tandem mass spectrometry (LC-MS/MS) to identify the 96 proteins adsorbed on the surface of the gold nanoparticles. Among the 20 most abundant proteins identified, 14 proteins were common in both AuNSs and AuNRs. We hypothesize that the adsorption of these proteins was due to their high sulfur content, allowing for their interaction with gold nanoparticles via the Au-S bond. The presence of distinct proteins on the surface of AuNSs or AuNRs was also investigated and possibly related to the competition between proteins present on the external layers of corona and gold nanoparticle morphology.

Visual Detection of Biomolecules Using Concentration Dependent Induced Aggregation of Plasmonic Gold Nanoparticles

Significant advancement has occurred in the detection methods of solution-based analytes. High-pressure liquid chromatography, gas chromatography, and other systems used for analyses are quite expensive. Therefore, there is a need for new methods and for the visible detection of analytes. Here, we demonstrate that 3-aminopropyl triethoxysilane (APTES) could impact the stability, optical, and morphology of gold nanoparticles (AuNps) in a colloidal solution. These impacts can be used to create a sensitive visual detection system. The strong impact of the APTES concentration on the ultraviolet–visible absorption spectra of the solutions is illustrated, which displays systematic and extensive red shifts. The presence of denatured proteins within a therapeutic drug product can induce a series of adverse effects. This report describes a fast, low cost, sensitive, and user-friendly platform where the plasmonic nanoparticles create visual biosensing of denatured proteins. Artificially heat stressed ferritin, glutathione, and insulin coupled to AuNps are exposed to ATES and upon denaturation of the protein or peptide, systematic blue or red shifts are observed in the absorbance spectra of the AuNps/biomolecules, and aminosilane solution. This serves as a proof-of-concept for a fast in-solution detection method for heat-stressed proteins or peptides.

Synthesis of gold nanoparticles (AuNPs) with improved anti-diabetic, antioxidant and anti-microbial activity from Physalis minima

BackgroundGold nanoparticles have come to prominence among noble metals due to their characteristics. Bio-transformed nanoparticles have a low toxicity and are biocompatible and ecologically benign. Physalis minima has been used in traditional medicine for its diuretic, laxative, and anti-inflammatory qualities since ancient times. MethodsGold nanoparticles are formed when water gold metal ions interact with an aqueous plant extract of Physalis minima (Au NPs). ResultsIn a UV–visible spectrophotometer, the resulting Au NPs formed a broad surface peak at 546 nm. According to the FTIR data, the peaks represent flavonoids, phenols and polyphenols meaning that flavonoids, phenols, and polyphenols were utilised as the reducing agent to create gold nanoparticles. According to the XRD pattern, the synthesised gold nanoparticles are crystalline in nature in a cubic system, with average particle sizes of roughly 36 nm. Gold nanoparticles were evaluated and found to have a zeta potential of −20.5mv, suggesting that they were stable and suitable for biological uses. The morphology of gold nanoparticles was confirmed using microscopic imaging. ConclusionThis study looked at the anti-oxidant, anti-diabetic, and antibacterial properties of gold nanoparticles (Au NPs) made from Physalis minima, making it exceedingly promising for biological applications.

Influence of surface moieties on nanomechanical properties of gold nanoparticles using atomic force microscopy

Physical attributes of nanoparticles synthesized for therapeutics are often studied as they are known to influence in vitro cellular and in vivo tissue uptake as well as their circulation. Surface chemistry of nanoparticles with biologics is known to control their physicochemical attributes including thermal, magnetic and optical but not nanomechanical properties. For specific bio-application, a wide variety of biologics have been immobilized on the nanoparticle surface. Using atomic force microscopy (AFM), here we present a comprehensive analysis of morphology and nanomechanical properties of gold nanoparticles (GNPs) conjugated with biologics, viz, nonapeptides and poly-ethylene glycol. We have optimized the applied force involved in the AFM measurements to avoid any structural alteration in biologics present on GNPs’ surface. The vertical dimensions of GNPs from AFM studies were in agreement with the hydrodynamic size obtained from Zetasizer. We also monitored that surface chemistry of GNPs significantly influence their nanomechanical attributes including Young’s modulus, adhesion, work of adhesion and surface free energy. The results from these studies demonstrate that surface alteration of GNPs shift the paradigm of their nanomechanical signatures.

Selectively Regulating the Chiral Morphology of Amino Acid-Assisted Chiral Gold Nanoparticles with Circularly Polarized Light.

Chiral nanomaterials have attracted increasing attention due to their versatile optical properties. Although circularly polarized (CP) light can serve as an inducer, it has negligible effects because of the short lifetime of the plasmonic states. Here, we propose that the site-selective chirality regulation on the morphology of cysteine (cys) amino acid-assisted chiral gold nanoparticles (cys-chiral AuNPs) can be realized through CP light irradiation. This can result in the increased or decreased circular dichroism (CD) signal intensity. The site-selective growth mechanism of the cys-chiral AuNPs is elucidated with light-matter interactions through the opposite rotation of right(R)/left(L) CP light. The site-selective chirality growth of the cys-chiral AuNPs is ascribed to the morphology evolution induced by the synergy of cys and R/L-CP light, which is clearly analyzed and elucidated with high CD intensities. This work provides a promising alternative strategy to produce high-chirality nanomaterials that can be applied in biomedicine and enantiomer photocatalytic reaction.

Charge and hydrophobicity of amyloidogenic protein/peptide templates regulate the growth and morphology of gold nanoparticles.

Biomolecules are known to interact with metals and produce nanostructured hybrid materials with diverse morphologies and functions. In spite of the great advancement in the principles of biomimetics for designing complex nano-bio structures, the interplay between the physical properties of biomolecules such as sequence, charge, and hydrophobicity with predictable morphology of the resulting nanomaterials is largely unknown. Here, using various amyloidogenic proteins/peptides and their corresponding fibrils in combination with different pH, we show defined principle for gold nanocrystal growth into triangular and supra-spheres with high prediction. Using a combination of different biophysical and structural techniques, we establish the mechanism of nucleation and crystal growth of gold nanostructures and show the effective isolation of intact nanostructures from amyloid templates using protein digestion. This study will significantly advance our design principle for bioinspired materials for specific functions with great predictability.

Restructuring of 4H phase Au nanowires and its catalytic behavior toward CO electro-oxidation

Au nanowires in 4H crystalline phase (4H Au NWs) are synthesized by colloid solution methods. The crystalline phase and surface structure as well as its performance toward electrochemical oxidation of CO before and after removing adsorbed oleylamine molecules (OAs) introduced from its synthesis are evaluated by high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), underpotential deposition of Pb (Pb-upd) and cyclic voltammetry. Different methods, i.e. acetic acid cleaning, electrochemical oxidation cleaning, and diethylamine replacement, have been tried to remove the adsorbed OAs. For all methods, upon the removal of the adsorbed OAs, the morphology of 4H gold nanoparticles is found to gradually change from nanowires to large dumbbell-shaped nanoparticles, accompanying with a transition from the 4H phase to the face-centered cubic phase. On the other hand, the Pb-upd results show that the sample surfaces have almost the same facet composition before and after removal of the adsorbed OAs. After electrochemical cleaning with continuous potential scans up to 1.3 V, CO electro-oxidation activity of the 4H Au sample is significantly improved. The CO electro-oxidation activity is compared with results on the three basel Au single crystalline surfaces reported in the literature, possible origins for its enhancement are discussed.

The electrodeposition of gold nanoparticles from aqueous nanodroplets.

Nanodroplet-mediated electrodeposition is a reliable method for electrodepositing nanoparticles by confining a small amount of metal-salt precursor in water nanodroplets (radius ∼400 nm) suspended in an oil continuous phase. This technique provides a great advantage in terms of nanoparticle size, morphology, and porosity. For an electrochemical reaction to proceed in the aqueous nanodroplet, the electroneutrality condition must be maintained. Classically, [NB4][ClO4] or a comparable salt is added to the oil continuous phase to maintain charge balance. Unfortunately, the presence of this salt in the oil phase causes some metal salts, such as HAuCl4, to phase transfer, disallowing the formation of gold nanoparticles. Here, we demonstrate the partitioning of HAuCl4 is orders of magnitude lower using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) when LiClO4 is added to the nanodroplet phase and [NBu4][ClO4] is not added to the continuous phase. This simple change allows for the electrodeposition of gold nanoparticles. Scanning electron microscopy shows the morphology and size distribution of gold nanoparticles obtained at different concentrations of LiClO4. Transmission electron microscopy in selected diffraction mode was used and it determined the gold nanoparticles obtained are polycrystalline with miller indices of (222) and (200). This work widens the variety of nanoparticles that can be electrodeposited from nanodroplets for applications in energy storage and conversion, photoelectrochemistry, and biosensing.

(Invited) Plasma Assisted Enhancement in Optical and Electronic Properties of Metal Nanoparticles: Application in Electrochemical Biosensing

The sensitivity enhancement of biosensors can be achieved by increasing the active surface area using nanoparticle-functionalized electrodes. However, these enhancements have certain limitations due to a lack of information about the properties of nanoparticles and their behavior under certain conditions arising due to polydispersity, orientation, and surface roughness.Nanoparticles (NPs) have broad spectra of their applications in electronics. In most sensing methods, the deposition of high-density NPs causes polydispersity. Hence, the distribution achieved on the electrode surface conceals the effects of their size-dependent properties. Moreover, the tethered patterning of recognition molecules on the electrode surface is always represented using simple sketches, which fail to consider the non-idealities in the target-surface arrangement. The data obtained in these cases are averaged over these phenomena is challenging to interpret.The interparticle interactions play an active role in enhancing the sensitivity of the biosensors; these interactions are controlled by the Van der Waals force of attraction and the Electrostatic double layer (EDL) on the surface. According to DLVO mode, the Van der Waals force and EDL on the surface of nanoparticles are dependent on average nanoparticle size, the distance between interacting surfaces, absolute temperature, stern layer thickness, and zeta potential. In this work, we present an experimental setup to control the nanoparticle distribution and the surface charges. The experimental methods consist of depositing nanoparticles by drop-casting, aerosol spraying, and atmospheric plasma-assisted aerosolized deposition (Figure 1).The studies are carried out to investigate the impact of atmospheric plasma treatment on the morphology and optical properties of gold nanoparticles (Au NPs). The morphological changes such as size reduction observed due to the surface plasma treatment of AuNPs are attributed to the symmetric partial oxidation. The plasma deposited films were used as SERS substrate to detect R6G peaks. The intensity of the SERS signal of R6G from plasma-treated AuNP substrate was ~95 times as high as that of the untreated substrate. This enhancement is attributed to the surface roughness, presence of nanogaps, and size reduction after the treatment of NPs on the substrates. The morphological changes are explained by a redox reaction induced by the energy and concentration of reactive species in the plasma environment.Surface architectures of electrochemical biosensors have complex structures which facilitate the effective capture of probes (analytes). A minor defect in the architecture can cause an error in probe-target interaction. In such electrochemical sensors, the primary assumption made is that the sensor has an ideal architecture. Nevertheless, these sensors drive the detection of analytes as the focus is on the probe-target interaction. The underlying surface properties due to the resultant architecture are overlooked while analyzing the detection phenomenon. Hence, assessing the dependence of the sensing process on the non-idealities present is required to achieve reliable measurements.This study also presents the plasma-induced enhancement of electrical properties of Au NPs at room temperature. The distribution of plasma-assisted aerosolized deposited NPs showed the promising architecture for surface modification of the electrochemical sensor that has improved the electrochemical sensing, which is validated by detecting the cortisol molecules (cortisol is a stress biomarker found in interstitial fluids, saliva, and sweat). This improved electrochemical response is due to plasma-assisted surface activation of NPs. Another reason for the enhancement is the increase in the density of NPs on the substrate leading to a larger electroactive surface area (Figure 2A, 2B).These NP functionalized electrodes were then modified using DTSP SAM (dithiobis(succinimidyl propionate) self-assembled monolayer) and cortisol antibodies to detect cortisol molecules. The enhancement in the sensitivity was observed for plasma-assisted AuNPs functionalized electrodes as against drop-casted and aerosol sprayed electrodes (Figure 3A, 3B, 3C, 3D).In summary, a novel technique of plasma-assisted NPs deposition, which could maintain the inter-particle repulsive barrier to obtain the uniform monolayer of NPs, is reported. This barrier potential was achieved due to the de-agglomeration of NPs during deposition using nebulizer in experimental assembly and providing the surface excitation and surface charge tuning of NPs during plasma-assisted deposition. The properties of plasma-treated NP films at room temperature are comparable to the thermally-treated films at higher temperatures. This unique feature can be used for processing metal nanoparticles at room temperatures for designing sensitive SERS substrates on flexible materials such as polymers, papers, and textiles. Figure 1