Nov 11, 2025

Public workspaceLIG-Gold electrodeposition  V.1

DOI
https://dx.doi.org/10.17504/protocols.io.n2bvjn9xbgk5/v1
  • Saylen Sofia Paz1,
  • Diana Vanegas1
  • 1Clemson University
Saylen S Koscelny
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DOI: https://dx.doi.org/10.17504/protocols.io.n2bvjn9xbgk5/v1
Protocol Citation: Saylen Sofia Paz, Diana Vanegas 2025. LIG-Gold electrodeposition . protocols.io https://dx.doi.org/10.17504/protocols.io.n2bvjn9xbgk5/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License,  which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: In development
We are still developing and optimizing this protocol
Created: June 09, 2024
Last Modified: November 11, 2025
Protocol Integer ID: 101463
Keywords: gold electrodeposition, electrodes via electrochemical deposition, electrochemical deposition, electrode
Abstract
This protocol describes a reproducible method to fabricate gold‑nanoparticle‑decorated laser‑induced graphene (LIG) electrodes via electrochemical deposition.
Troubleshooting
Overview
This protocol describes the process of gold electrodeposition on laser-induced graphene (LIG) electrodes by the chronoamperometry technique using a MultiPalmSens4. Figure 1 depicts the process. The time must be changed according to the number of samples you have. The resulting LIG/Au electrode is suitable for biosensing applications, including pathogen detection, enzymatic sensing, and aptamer-based assays.


Figure 1. Electrodeposition of Laser Induce Graphene Electrodes


Materials and reagents
  • Kapton film (electrical grade polyimide film, 0.0050″ thick)
  • Chemical-resistant polyvinyl chloride (PVC) sheets (1/16” thick)
  • Metal alloy tape
  • Lacquer (passivation coating)
  • Deionized water (DI)
  • Isopropyl alcohol (IPA)
  • Gold(III) chloride trihydrate (HAuCl₄·3H₂O)
  • Sulfuric acid (H₂SO₄), 1 N (Note: 1 N H₂SO₄ corresponds to 0.5 M H₂SO₄ because H₂SO₄ is diprotic; see preparation notes below.)
  • Silver/silver chloride (Ag/AgCl) reference electrode
  • Gold-wire counter electrode
  • Female USB 2.0 (Type A) connectors
Equipment and software
  • Universal Laser System (VLS3.60) and CorelDRAW (Corel Corporation)
  • Potentiostat: Multi PalmSens4 (PalmSens BV, Houten, The Netherlands) with MultiTrace software.
  • Magnetic stirrer (capable of 500 rpm) and standard three-electrode cell stand.
  • Standard laboratory glassware, pipettors, and safety equipment.
Platform fabrication (LIG)
  • Design a three-electrode layout (working, reference, counter) in CorelDRAW
  • Laser inscription settings: distance from lens to sample surface = 5.0 cm; one scan; burn-in power pulse = 40 ms; 75% pulses per inch; burn-in speed = 1000. (Adjust as needed for your laser model.)
  • Apply metal tape at the electrode pads to serve as robust bonding pads and to protect LIG during electrical connections.
  • Apply a thin layer of lacquer as passivation over the electrode shafts, leaving the active working area exposed.
  • Rinse electrodes briefly with DI water, allow to dry, and store in a dust-free container until use.
Gold Electroplating Solution Preparation
5.0 mM HAuCl₄ prepared in 0.5 M H₂SO₄.
Note: if using 1 N H₂SO₄ stock (≈0.5 M), the 1 N solution can be used directly as the supporting electrolyte and diluted accordingly when preparing the final plating solution
Equipment Setup
  • Assemble a three-electrode cell: LIG working electrode (immersed working area exposed to solution), Ag/AgCl (3 M KCl) reference electrode, and a Pt-wire counter electrode (or a gold wire if preferred for charge balance — ensure consistent method across experiments). Connect to the Multi PalmSens4 potentiostat.
  • Place the cell on a magnetic stirrer and set stirring to 500 rpm (continuous stirring during deposition).
Gold electrodeposition
  • Using the chronoamperometry technique, set a constant potential of −0.90 V (vs Ag/AgCl) for 240 s (4 minutes).
  • Ensure the working area is fully and reproducibly immersed in the plating solution.
  • After deposition, immediately remove the electrode and rinse thoroughly with DI water.
  • Optionally, perform additional characterization (SEM, EDX, or electrochemical impedance spectroscopy) if instrumentation is available

💡 Tips
Safety (acid handling): When preparing or diluting sulfuric acid, always add acid to water (never water to acid). Use appropriate PPE: acid-resistant gloves, lab coat, eye protection, and work in a fume hood when handling concentrated acids.
Protocol references
Tang, Y., Casso Hartmann, L., Bahamon Pinzon, D., Am Moreira, G., Vanegas, D., & S McLamore, E. (2022). Electrochemical analysis of laser-inscribed graphene electrodes using cyclic voltammetry (ferri/ferrocyanide redox couple) v2. Springer Science and Business Media LLC. https://doi.org/10.17504/protocols.io.4r3l27q7jg1y/v2

Rauf, S., Lahcen, A. A., Aljedaibi, A., Beduk, T., Ilton de Oliveira Filho, J., & Salama, K. N. (2021). Gold nanostructured laser-scribed graphene: A new electrochemical biosensing platform for potential point-of-care testing of disease biomarkers. Biosensors and Bioelectronics, 180, 113116. https://doi.org/10.1016/j.bios.2021.113116