Gold Patterns Research Articles

Flexible, Electrochemical Skin-Like Platform for Inflammatory Biomarker Monitoring.

Addressing global challenges in wound management has greatly encouraged the emergence of home diagnosis and monitoring devices. This technological shift has accelerated the development of new skin patch sensors for continuous health monitoring. A key requirement is the creation of flexible platforms capable of mimicking human skin features. Here, for the first time, an innovative, highly adaptable electrochemical biosensor with molecularly imprinted polymers (MIPs) is customized for the detection of the inflammatory biomarker interleukin-6 (IL-6). The 3-electrode gold pattern is geometrically standardized onto a 6µm thick polyimide flexible membrane, an optically transparent, and biocompatible polymeric substrate. Subsequently, a biomimetic sensing layer specifically designed for the detection of IL-6 target is produced on these transducers. The obtained MIP biosensor shows a good linear response within the concentration range 50pgmL-1-50ngmL-1, with a low limit of detection (8pgmL-1). X-ray photoelectron spectroscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy characterizations confirm the modifications of the flexible gold transducer. After optimization, the biosensing device shows remarkable potential in terms of sensitivity, selectivity, and reproducibility. Overall, the integration of a low-cost electrochemical sensor on biocompatible flexible polymers opens the way for a new generation of monitoring tools with higher accuracy, less invasiveness, and greater patient comfort.

Dissolution patterns of gold on various structural surfaces in thiosulfate solutions: The effect of interface adsorption on thiosulfate oxidation and gold atom dissociation

Passivation caused by the adsorption and decomposition of thiosulfate on gold surfaces significantly influences the leaching rate of gold. The surface structure often determines the reactivity of an interface. Studying the effects of different surfaces on the decomposition of thiosulfate ions and gold dissolution can provide insights into the passivation formation mechanism. In this study, the oxidation of thiosulfate on different surfaces is investigated using linear voltammetry. The oxidation response of thiosulfate was weaker on granular (1 1 1) and (5 4 1) surfaces than on nanoflakes with (1 1 1) surface. Furthermore, the Tafel test results indicate that the potential for gold dissolution is higher on the granular (1 1 1) and (5 4 1) surfaces, leading to a smaller current value of gold dissolution. Raman spectroscopy indicates that the response signals of the polysulfides and polythionate were stronger on the granular (1 1 1) and (5 4 1) surfaces. The chemical bond changes of thiosulfate adsorbed on different surfaces are studied through molecular simulations based on density functional theory. These results indicate that as the saturation of surface gold atoms decreases, their reaction activity increases, and the bonding effect with thiosulfate ions becomes stronger during adsorption. The changes in the SS bonds in thiosulfate reflect the influence of the different surfaces on their stability. On the (1 1 1) surface, the SS bond changes from the initial 2.102 Å to the adsorbed 2.254 Å, while on the (5 4 1) surface, the SS bond changes to 2.274 Å Although the reaction activity of the granular (1 1 1) and (5 4 1) surfaces is high, the energy barrier for dissociating individual gold atoms from them is higher. The adsorption of sulfur-containing substances on the surface, along with the increased energy barrier for gold dissociation are both factor contributing to the greater difficulty of gold dissolution from granular (1 1 1) and (5 4 1) surfaces.

Controlled circular dichroism with graphene-based metamaterial for terahertz wave

This article explores the design and analysis of a metal-graphene hybrid metamaterial structure tailored for tunable circular dichroism (CD) effects in the terahertz (THz) frequency regime. Chiral metamaterials have garnered considerable interest in photonics due to their versatile applications, including sensing, polarization manipulation, and chiral imaging. The proposed metamaterial unit cell features four meta-atoms with C4 rotational symmetry, composed of gold on a polyimide substrate. By strategically integrating the graphene sheets above the gold patterns, selective control over the absorption efficiency for the incident wave of left-handed circularly polarized (LCP) and right-handed circularly polarized (RCP) light is achieved. The study demonstrates that adjusting graphene chemical potential enables precise modulation of CD from 0.80 to 0.10 across a wide THz frequency spectrum. Furthermore, the article investigates the structure optical response for incident angles ranging up to 75°, revealing stable CD behavior up to 30° and intriguing dual-band effects beyond 50°. These findings underscore the potential of the proposed metamaterial for practical applications in photonics, sensing, and chiral imaging, offering tunable control over the CD effects in the THz regime.

Thermal annealing induced graphite/diamond structure processed by high-voltage hydroxide ion treatments

Ohmic contacts with low specific contact resistance are necessary for fabrication of diamond electronic devices. This work reports that graphite/diamond ohmic contacts can be obtained by thermal annealing of diamond, patterned by hydroxide ion treatment. Surface graphitization of diamond is achieved through rapid thermal annealing at 1050 °C in vacuum. The thickness of graphite layer is found to be dependent on the duration of annealing with an approximate rate of 3.3 ∼ 3.6 nm/minute. The alteration in surface structure is analyzed using Raman spectra, showing a continuously enhanced G peak with increasing annealing time. Early stages of graphitization are discovered by X-ray photoelectron spectroscopy, after annealing diamond samples for merely 0.5 ∼ 2 min. Additionally, a distinct atomic interface between graphite and diamond is observed via cross-sectional transmission electron microscopy. Further, the surface graphite is selectively etched by hydroxide ion treatments, protected by gold patterns. In the end, the specific contact resistance of the graphite/diamond contact is determined to be 2.53 × 10-4 Ω cm2 employing the transmission line model.

High‐resolution patterning on LTCC by transfer of photolithography‐based metallic microstructures

AbstractThe growing applications and constant miniaturization of electronic devices and of low‐temperature co‐fired ceramics (LTCC) in various fields, such as aviation, telecommunications, automotive, satellite communications, and military, have led to an increase in the demand for LTCC. Such prospects arise due to the continuous scaling down of components and high‐density interconnection in electronics packaging. This paper reports a technique for the transfer of high‐resolution microstructures from silicon substrates to LTCC. In this method, gold and copper patterns were formed by photolithography, electrodeposition, and residual layer stripping on silicon substrate. Lithography provides the opportunity to create and transfer complex patterns for use in several different applications and electroplating enables the use of pure metal for excellent electrical properties. The developed structures were transferred onto a top layer of LTCC tape using hot embossing. Then, the subsequent layers were stacked, laminated, and sintered. A resolution of 1.5 μm after free sintering and 4.5 μm after pressure‐assisted sintering was achieved. This distinctive method can be useful for several applications requiring high‐resolution and superior electrical properties.

Active dual-control terahertz electromagnetically induced transparency analog in VO2 metasurface

In this paper, an active dual-control electromagnetically induced transparency (EIT) analog is realized by using vanadium dioxide (VO2) metasurface on a sapphire substrate. The unit cell of the metasurface is a composite-split-ring-resonator (CSRR) composed of two resonators, one of which containing gold pattern and VO2 is named as VSRR and the other containing two T-type resonators is called TTR. The resonant frequency of VSRR and that of TTR are located at 0.43 and 0.75 THz, respectively. While, the CSRR have two resonant frequencies at 0.39 and 0.72 THz, and an EIT-like band has a central frequency at 0.56 THz. When the metasurface is electrically stimulated, the insulator-to-metal-transition (IMT) of VO2 can result in the reconstruction of the metasurface. Therefore, the EIT resonance can be controlled by bias voltages. At central frequency of 0.56 THz, a modulation depth of 87.7% and a group delay of 2.7 ps are obtained. The EIT mechanism is further explained by using a coupled Lorentz model, and theoretical calculation and simulation show good agreement with the experiment. Moreover, by mechanically adjusting the incidence angle, the adjustable EIT-like phenomenon is also observed and the modulation depth achieves 73%. This work paves a way for the development of THz modulators, switches, and slow light devices.

Study of the basic laws of dissolution of gold and copper in solutions with an ultra-low concentration of sodium cyanide

The work sets out to study the basic physicochemical dissolution patterns of gold, copper, and natural copper-containing minerals (chalcopyrite, bornite and azurite) in solutions with an ultra-low concentration of sodium cyanide (from 0.102∙10-3 to 4.08∙10-3 mol/L). The influence of various factors on the rate of dissolution of Au and Cu in solutions with ultra-low NaCN concentrations was studied by the rotating disk method; for natural copper minerals, the powder diffraction method was used. The concentration of gold and copper in solutions was determined by atomic absorption analysis. The chemical composition of the studied copper minerals was determined using the X-ray phase method, while the specific surface of the minerals was detected using a laser granulometer. The process of gold dissolution is shown to proceed in both diffusion and kinetic regions. In the diffusion region, the rate constant was 0.334∙10-6 L∙cm-2∙s-1/2∙rad-1/2; in the kinetic region – 0.919∙10-6 L∙cm-2∙s-1/2. The calculated value of the apparent activation energy for the diffusion region was 22.5 kJ/mol; for the kinetic region – 40.1 kJ/mol. The addition of glycine to a solution with an ultra-low concentration of sodium cyanide is shown to increase the specific dissolution rate of gold by 1.2 times: from 0.692∙10-9 to 0.82∙10-9 mol/cm2∙s. The process of copper dissolution is shown to take place in the diffusion r egion. The rate constant was 0.496∙ 10-6 L∙cm-2∙s-1/2∙rad-1/2 at an activation energy of 17.0 kJ/mol. With a fractional supply of sodium cyanide, the dissolution rate of copper minerals is reduced by 10–30% compared to a single load. The calculated apparent activation energy values for chalcopyrite, bornite, and azurite were 22.03, 24.2, and 24.1 kJ/mol, respectively. Thus, the use of ultra-low concentrations of NaCN in the process of cyanidation of gold and copper has a positive effect, which can be used i n the processing of gold-copper raw materials to significantly reduce the consumption of sodium cyanide.

Dynamically switchable broadband–narrowband terahertz metamaterial absorber based on vanadium dioxide and multilayered structure

We propose and demonstrate a terahertz metamaterial absorber based on vanadium dioxide (VO2) and multilayered structure with dynamically switchable broadband and narrowband absorption. Its main structure is a double absorption layer composed of VO2 rings and gold pattern. Through adjusting the conductivity of VO2, the absorber can actively transform between broadband absorption of greater than 90% in the frequency range of 2.6 THz to 6.28 THz and narrowband absorption of greater than 99.9% at 7.77 THz. A particular explanation of physical absorption mechanism based on electromagnetic resonance is presented by electromagnetic field distributions and the impedance matching theory. Furthermore, the influence of the absorption layer patterns and structural parameters on the absorber performance cannot be ignored. This absorber structure also has the features of polarization insensitivity and incident wide-angle admissibility. Compared with recent studies, the absorber has improved in absorption bandwidth with the simpler design in the number of layer. The proposed absorber may find some important applications in the modulation, sensing and imaging fields.

Patterning of Hydrophilic and Hydrophobic Gold and Magnetite Nanoparticles by Dip Pen Nanolithography (Small 18/2023)

Dip Pen Nanolithography In article number 2208069, Bart Jan Ravoo and co-workers report the surface patterning of nanoparticles using dip pen nanolithography. Metal and metal oxide nanoparticles functionalized with various organic ligands can be patterned in nanosized clusters. Depending on the polarity of the ligand shell, water or toluene is used as ink solvent. No modification of atomic force microscope (AFM) tip or substrate surface is required.

Print‐Light‐Synthesis of Gold Thin Film Electrodes for Electrochemical Sensing

AbstractThe one‐step fabrication of gold films by inkjet printing of a gold precursor ink and its photochemical reduction by exposure to UV light is presented. Inkjet printing creates on a substrate with high control micrometer‐thin reaction volumes in which upon direct high‐intensity light irradiation, the gold precursor reduces to pure and well‐adhered Au particles, while all other ink components escape in the gas phase, without the need for any further post‐treatment. The Au precursor ink does neither contain stabilizing agents, such as polymers or surfactants, nor sacrificial compounds, such as photoinitiators, to initiate and accelerate the reduction. This economic and green process is known as Print‐Light‐Synthesis (PLS) and is herein used to create gold patterns of thin compact Au films and separated Au nanoparticles. Gold loadings are in the µg cm−2 range and precisely controlled, thanks to the inkjet printing parameters. The gold films are characterized by spectroscopic and electrochemical methods. Finally, the applicability of Au films as electrochemical sensors is demonstrated for the detection of 1,4‐butanediol in comparison to a commercial screen‐printed Au electrode. The PLS Au electrode shows a 20 times higher sensitivity and opens new possibilities for disposable electrode production.

Patterning of Hydrophilic and Hydrophobic Gold and Magnetite Nanoparticles by Dip Pen Nanolithography.

Nanoparticles offer unique physical and chemical properties. Dip pen nanolithography of nanoparticles enables versatile patterning and nanofabrication with potential application in electronics and sensing, but is not well studied yet. Herein, the patterned deposition of various nanoparticles onto unmodified silicon substrates is presented. It is shown that aqueous solutions of hydrophilic citrate and cyclodextrin functionalized gold nanoparticles as well as poly(acrylic) acid decorated magnetite nanoparticles are feasible for writing nanostructures. Both smaller and larger nanoparticles can be patterned. Hydrophobic oleylamine or n-dodecylamine capped gold nanoparticles and oleic acid decorated magnetite nanoparticles are deposited from toluene. Tip loading is carried out by dip-coating, and writing succeeds fast within 0.1s. Also, coating with longer tip dwell times, at different relative humidity and varying frequency are studied for deposition of nanoparticle clusters. The resulting feature size is between 300 and 1780nm as determined by scanning electron microscopy. Atomic force microscopy confirms that the heights of the deposited structures correspond to a single or double layer of nanoparticles. Higher writing speeds lead to smaller line thicknesses, offering possibilities to more complex structures. Dip pen nanolithography can hence be used to pattern nanoparticles on silicon substrates independent of the surface chemistry.

The Fabrication of Gold–Silver Bimetallic Colloids by Microplasma: A Worthwhile Strategy for Counteracting the Surface Activity of Avian Influenza Virus

In the present project, fructose-stabilized gold, silver and gold–silver bimetallic colloids have been synthesized by the electrochemical reduction of HAuCl4·3H2O (Au precursor) and AgNO3 (Ag precursor), employing the atmospheric pressure microplasma technique. X-Ray Diffraction patterns of gold–silver bimetallic particles exhibit (111), (200) and (220) planes identical to gold and silver NPs depicting FCC structures. The decrease in the peak intensities of Au–Ag (111) and Au–Ag (200) as compared to those of Au (111) and (200) is due to the formation of Au–Ag alloys. The FE-SEM image of gold–silver bimetallic NPs has revealed an adequate change in morphology as compared to the morphology of gold NPs and silver NPs. The majority of the gold–silver bimetallic NPs are spherical and are uniformly dispersed. The EDS spectra of (Au–Ag) confirm the presence of metallic gold and silver. The appearance of a single Surface Plasmon Resonance (SPR) peak in the UV–VIS absorption spectra of gold–silver colloids and its position in between the SPR peaks of the UV–VIS absorption spectra of gold and silver colloids justify the formation of gold–silver bimetallic alloy particles. In DLS measurements, the size distribution of gold–silver bimetallic colloids carries a narrow range 55 to 117 nm as compared to the size distribution of gold and silver colloids. The compatibility of the sizes of these colloids and the influenza virus belonging to the Orthomyxoviruses family (size range 80–300 nm with different morphologies) are assumed to stand responsible for an effective bio-conjunction with Influenza viruses. Au–Ag bimetallic nanostructures have synergistically improved their antiviral activity against H9N2 influenza virus as compared to monometallic AuNPs and AgNPs. Thus, the Au–Ag nanostructured alliance has been proven to be more effective and is capable of manifesting high antiviral efficacy.

Computer-aided diagnosis of primary membranous nephropathy using expert system

BackgroundThe diagnosis of primary membranous nephropathy (PMN) often depends on invasive renal biopsy, and the diagnosis based on clinical manifestations and target antigens may not be completely reliable as it could be affected by uncertain factors. Moreover, different experts could even have different diagnosis results due to their different experiences, which could further impact the reliability of the diagnosis. Therefore, how to properly integrate the knowledge of different experts to provide more reliable and comprehensive PMN diagnosis has become an urgent issue.MethodsThis paper develops a belief rule-based system for PMN diagnosis. The belief rule base is constructed based on the knowledge of the experts, with 9 biochemical indicators selected as the input variables. The belief rule-based system is developed of three layers: (1) input layer; (2) belief rule base layer; and (3) output layer, where 9 biochemical indicators are selected as the input variables and the diagnosis result is provided as the conclusion. The belief rule base layer is constructed based on the knowledge of the experts. The final validation was held with gold pattern clinical cases, i.e., with known and clinically confirmed diagnoses.Results134 patients are used in this study, and the proposed method is defined by its sensitivity, specificity, accuracy and area under curve (AUC), which are 98.0%, 96.9%, 97.8% and 0.93, respectively. The results of this study present a novel and effective way for PMN diagnosis without the requirement of renal biopsy.ConclusionsThrough analysis of the diagnosis results and comparisons with other methods, it can be concluded that the developed system could help diagnose PMN based on biochemical indicators with relatively high accuracy.Graphical

Геохимическая зональность рудной залежи Ново-Учалинского колчеданного месторождения (Южный Урал, Россия)

Novo-Uchaly essentially zinc (CZn>>CCu) VMS deposit is one of the largest in the Urals. Currently, it is under additional exploration by fans of underground drilling wells and mine workings. The paper describes a novel geochemical zonation of the sulphide deposit (the example of Cu, Zn, Au and In), discusses conditions of formation and factors that caused its complication. We carried geostatistical calculations in addition to the analysis of the zonation of the deposit. The ore deposit is represented by a large subvertical ribbon of a whimsical structure, inclined southward, which is confined to the wing of an inverted large anticlinal fold, cut by mafic dikes and characterized by a complex, combined geochemical zonality. The distribution of Cu and Zn is generally asymmetric. Copper-rich ores tend to the northern wedge of the deposit, and to the south, along its declination, the concentration of Zn increases, while Cu decreases, and the middle part of the deposit is represented by zinc-rich ores. In the section, copper maxima are more often noted in the footwall side of the deposit, and zinc — in the hanging side. The intrusion of a thick gabbro-diorite dyke and subsequent dynamometamorphism, including hydrothermal solutions, caused the redeposition of more mobile Cu in the near-contact zones of the dyke and areas of swell of the ore body thickness. Within the swell of the thickness of the deposit, in the hinge of the fold of the 2nd order, rich copper-zinc ores occur, which are enriched by Zn, Pb, Au, Ag, In, Ba and some other rare elements. The similarity of their behavior in ores is confirmed by their high positive pair correlation. In the ore body, the distribution patterns of gold and indium are rather symmetrical. High concentrations of gold and indium are confined to a sharp bend in the ore body, and small indium maxima occur in the footwall of the ore lode. As a result of dynamometamorphism, the deposit acquired a whimsical structure with the formation of thick swells; ores were significantly recrystallized, and locally enriched by non-ferrous and precious metals.

Neural-Network-Based Adaptive Model Predictive Control for a Flexure-Based Roll-to-Roll Contact Printing System

High-precision contact force control is essential for continuous roll-to-roll contact printing via mechanical contact on flexible web substrates using stamps. Nonuniformly controlled stamp contact force will cause failures during printing, especially for large-area printing processes. Due to their high precision in positioning and force control, flexure mechanisms have been applied in roll-to-roll contact printing systems; however, conventional physical model-based control systems cannot manage the nonlinear effects that exist in flexure-based roll-to-roll contact printing systems. To achieve precise contact force control, we propose a neural-network-based adaptive model predictive control for a flexure-based roll-to-roll contact printing system. The nonlinearity of the flexure mechanism is learned and modeled by an artificial neural network. To eliminate the steady-state error caused by model mismatches and external disturbances, an online adaptive mechanism is designed via updating the biases of the output layer of the neural network model. Experimental results show that the root-mean-square error of the contact force can be controlled in the range of 0–0.075 N with balances on two ends of the print roller, outperforming a proportional–integral–derivative controller, a neural-network-based standard model predictive control (MPC) controller, and a neural-network-based robust MPC controller. The proposed control algorithm is implemented in a microcontact printing process that prints 45- <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m width gold patterns and achieves a variation of 0.3 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m in the average gold line width at different locations on an 88.9-mm width flexible substrate. The uniform microscale printing results have shown the effectiveness of the proposed neural-network-based adaptive model predictive control in the applied printing process.

Chemical vapor deposition growth of tin oxide nanowires for electrochemical sensor development

AbstractThis paper reports a growth of tin oxide nanowires on gold patterns by chemical vapor deposition. A 90 nm gold layer was deposited on a silicon wafer using a sputtering system and pre‐pattern by lift‐off techniques. Tin oxide nanowires were selectively grown on the gold pattern by chemical vapor deposition technique with 750°C and 5 × 10‐2 torr. High resolution transmission electron microscopy measurements showed that nanowire possessed a single crystal nature with tetragonal crystal system and the calculated lattice constants (a = 0.474 nm; c = 0.318 nm) were closed to those of standard pattern of SnO2. The ready SnO2 nanowire grown on the gold patterns were investigated for electrochemical sensor development.

VO2-enabled transmission-reflection switchable coding terahertz metamaterials.

Coding metamaterials have offered unprecedented degrees of freedom to manipulate electromagnetic waves in time and frequency domains in terms of various coding sequences, however, it is still challenging to realize dynamic coding metamaterials in the terahertz range. Here, we propose VO2-enabled transmission-reflection switchable coding terahertz metamaterials consisting of multilayered gold and VO2 patterns. The insulator-to-metal transition of VO2 leads to switch between the refractive and reflective scattering beams by changing the temperature. The four 2-bit elements are used to construct coding metasurface-based OAM generator with l = 1. Remarkably, the transmission-reflection switching functionality of the coding metasurface can be achieved at different frequencies. In addition, the novel designs in our work can achieve EM waves manipulation and provide a useful method to dynamically switch transmission-reflection response in the THz frequency regime.

Research on price forecasting and trading strategy based on data insight

The goal of establishing the model in this paper is to find the historical price patterns of gold and bitcoin according to the data provided. The purpose is to maximize returns under various market constraints and avoid loss risk as much as possible. Traders provide the best trading strategy. In this paper, two models are established: model 1: price prediction model based on ARIMA; Model 2: quantitative trading strategy model based on dynamic programming. For Model 1, a classical time series modeling approach based on stock forecasting was used: the ARIMA price forecasting model. The model's validity was demonstrated by analyzing the intrinsic trend of the data movements and verifying the smoothness. Next, historical data were used to fit the parameters of ARIMA, and the forecasting model was determined to be ARIMA (0, 1, 0) by the exhaustive method. Finally, the ARIMA predicts the up and down trends of gold as well as bitcoin, which provides the basis for the trading decision. For Model 2, to better quantify the relationship between investment risk and investment return, the Sharpe ratio is introduced, the Sharpe ratio's value is used as the main parameter of the trading strategy, and the corresponding planning equation is established. Then, based on the up and downtrend of the data predicted by the ARIMA model, the assets are allocated for investment. The model is optimized by a particle swarm algorithm, which accelerates the convergence of the model. Finally, this paper tests the model's accuracy to verify the correctness of the model. By adjusting the commission rate, it is found that the commission rate is negatively correlated with the number of large transactions of gold and bitcoin.

Room-Temperature Annealing-Free Gold Printing via Anion-Assisted Photochemical Deposition.

Metal patterning via additive manufacturing has been phasing-in to broad applications in many medical, electronics, aerospace, and automotive industries. While previous efforts have produced various promising metal-patterning strategies, their complexity and high cost have limited their practical application in rapid production and prototyping. Herein, a one-step gold printing technique based on anion-assisted photochemical deposition (APD), which can directly print highly conductive gold patterns (1.08 × 107 S m-1 ) under ambient conditions without post-annealing treatment, is introduced. Uniquely, the APD uses specific ion effects with projection lithography to pattern Au nanoparticles and simultaneously sinter them into tunable porous gold structures. The significant influence of kosmotropic or chaotropic anions in the precursor ink on tuning the morphologies and conductivities of the printed patterns by employing a series of different ions, including Cl- ions, in the printing process is presented. Additionally, the resistance stabilities and the electrochemical properties of the APD-printed gold patterns are carefully investigated. The high conductivity and excellent conformability of the printed Au electrodes are demonstrated with reliable performance in electrophysiological signal delivery and acquisition for biomedical applications. This work exploits the potential of photochemical-deposition-based metal patterning in flexible electronic manufacturing.

Electro- and photochemical studies of gold (III) bromide towards a novel laser-based method of gold patterning

In this report, we demonstrate a novel technique for the microscopic patterning of gold by combining the photoreduction of AuIIIBr4 − to AuIBr2 − and the electrochemical reduction of AuIBr2 − to elemental gold in a single step within solution. While mask-based methods have been the norm for electroplating, the adoption of direct laser writing for flexible, real-time patterning has not been widespread. Through irradiation using a 405 nm laser and applying a voltage corresponding to a selective potential window specific to AuIBr2 −, we have shown that we can locally deposit elemental gold at the focal point of the laser. In addition to demonstrating the feasibility of the technique, we have collected data on the kinetics of the photoreduction reaction in ethanol and have deduced its rate law. We have confirmed the selective deposition of AuIBr2 − within a potential window through controlled potential electrolysis experiments and through direct measurement on a quartz crystal microbalance. Finally, we have verified local deposition through scanning electron microscopy.