Microscope Slide With Integrated Electrodes

This project demonstrates how to build a flat microscopy cell with integrated electrodes, allowing you to apply an electric field while observing a sample in real time under a microscope (a home made and modified OpenFlexure in our case).

This setup is extremely useful for studying:

1. Electro-optical phenomena
2. Microfluidics
3. Interfacial chemistry
4. Biological responses to electric fields

The device consists of two conductive tracks separated by a small gap, creating a controlled electric field in a thin observation chamber.

To build the electrode microscope slide, you will need:

Core Components

1. Glass microscope slides or alternative PS Crystal 76x25 mm. The PS Crystal is housed in a CD case.
2. Conductive electrodes (thin metal strips, ITO coating, or copper tape)
3. Double-sided adhesive thin tape (0.3mm thickness)

Electrical Setup

1. Low-voltage power supply (DC or AC depending on application)
2. 2 Connecting wires

Optional for experiments

1. function generator (see SciencExpert Book "Electronic for Chemists - Wave Generator")

Preparation Tools

1. Isopropyl alcohol (for cleaning)
2. Tweezers
3. Gloves and lint-free wipes

Optional

1. 2 Polarizers(highly recommended for optical studies)
2. Camera for recording experiments

Microscope

We use a homemade and modified open flexure microscope.

Preamble : Prepare the Substrate

1. Thoroughly clean the glass slides and electrodes using isopropyl alcohol.
2. Ensure there is no dust or grease contamination.

1. Prepare the Adhesive Electrode Layer

1. Take a sheet of double-sided adhesive film.
2. Remove the protective liner from one side.
3. Carefully laminate this exposed adhesive surface onto the copper tape (copper-clad film).
4. Press firmly to ensure uniform adhesion and avoid trapped air.

2. Cut the Electrodes

1. Using a precision cutter, cut two strips approximately 1 mm wide from the copper-clad adhesive sheet.
2. These strips will serve as your electrodes.

3. Place the First Electrode

1. Remove the protective layer from the adhesive side of the first copper strip.
2. Place it onto the PS crystal microscope slide (plastic microscope substrate).
3. Ensure it is straight and well adhered.

4. Place the Second Electrode

1. Repeat the same process for the second strip.
2. Position it parallel to the first electrode, leaving a gap between 0.1 mm and 0.5 mm.
3. This gap defines the active electric field region.

5. Expose the Top Adhesive Layer

1. Once both electrodes are correctly positioned, remove the remaining protective layer from the double-sided adhesive.
2. This will expose the bonding surface for the top slide.

6. Seal the Cell

1. Place a second PS crystal slide on top of the assembly.
2. Apply gentle, uniform pressure to ensure proper sealing and consistent thickness of the chamber.

7. (Optional) Electrical Connections

1. For more reliable electrical contact:
2. Apply a small amount of rosin (flux) onto the copper electrodes to improve wettability.
3. Add a small layer of solder (tin)
4. Solder thin electrical wires onto each electrode.
5. Ensure connections are solid but avoid overheating, which could damage the plastic slide.
6. Reinforce the connexion with epoxy glue

This setup enables a wide range of experiments across multiple disciplines:

1. Liquid Crystals

1. Molecular alignment under electric field
2. Phase transitions (nematic ↔ isotropic)
3. Defect dynamics and texture evolution

2. Biology & Biophysics

1. Cell motion via dielectrophoresis
2. Alignment of microorganisms
3. Membrane response to electric stimulation
4. Cell viability testing

3. Interfacial Chemistry

1. Crystal nucleation and growth
2. Localized precipitation
3. Surfactant behavior and wetting effects

4. Electrochemistry

1. Local electrodeposition
2. Corrosion processes
3. Redox reactions at interfaces
4. Micro-electrolysis

5. Materials Science

1. Conductive film testing
2. Percolation in composites
3. Thin film deformation
4. Coating inspection

6. Colloids and Suspensions

1. Particle aggregation
2. Chain formation under electric field
3. Controlled flocculation

7. Microfluidics

1. Droplet manipulation
2. Interface dynamics
3. Confined flow behavior

8. Photonics & Optical Materials

1. Electro-optical modulation
2. Birefringence changes
3. Light transmission variation

9. Corrosion & Degradation Studies

1. Initiation of corrosion
2. Localized attack visualization
3. Passive layer breakdown

10. Education & Demonstration

1. Visual demonstration of electric field effects
2. Laboratory teaching experiments
3. Real-time physics visualization

1. Always start with low voltage and increase gradually
2. Avoid highly conductive solutions unless required
3. Record experiments (video preferred for dynamic processes)
4. Keep a control sample without electric field
5. Monitor temperature and avoid overheating
6. For biological samples, ensure medium compatibility

1. Bard, A. J., Mirkin, M. V. — Scanning Electrochemical Microscopy, CRC Press, 2022
2. Kanoufi, F. — Electrochemical Microscopy, L’Actualité Chimique, 2007
3. Hapiot, P. — Scanning Electrochemical Microscopy, L’Actualité Chimique, 2007
4. Liu, H. Y. et al. — Scanning Electrochemical and Tunneling Ultramicroelectrode Microscopy, JACS, 1986
5. Techniques de l’Ingénieur — Electrochemical Microscopy Dossier, 2026
6. Evident Scientific — Electrode Fabrication and Microscopy Applications
7. Société Chimique de France — Electrochemical and Interface Studies

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