High-performance Ag/AgCl conductive paste for reference electrodes, sensors, and printed electronics

Sigma-Aldrich™ Silver/Silver Chloride (Ag/AgCl) Paste (60/40) is a highly conductive, screen-printable reference electrode paste designed for fabrication of electrochemical sensors, diagnostic devices, environmental monitoring electrodes, and flexible printed electronics. With a precisely controlled 60% silver / 40% silver chloride ratio, this paste delivers excellent electrochemical stability, consistent potential behavior, and efficient conductivity for high-performance sensor platforms.

This material is supplied as a ready-to-print paste, optimized for polyester mesh screens and low-temperature curing. It is widely used in academic research, environmental analysis, biomedical diagnostics, and printed electronics manufacturing.

Key Features & Benefits

High Electrochemical Stability

• Ideal for forming reference electrodes in voltammetric, potentiometric, and amperometric systems
• Reliable and reproducible electrode potential under varied environmental and ionic conditions

Optimized Conductivity & Performance

• Sheet resistivity <100 mΩ/sq (20 µm thick film on alumina)
• High signal consistency for analytical and sensing applications
• Provides robust adhesion to a wide variety of substrates

Screen-Printing Optimized

• Coverage: 200 cm²/g (156 mesh polyester screen)
• Viscosity: 2.0–5.5 Pa·s for excellent print definition
• Long screen life (>3 hours) for production-scale workflows
• Suitable for semi-automatic and manual screen printers
• Not recommended for stainless steel mesh (corrosion possible)

Low-Temperature Curing

• 60°C for 30 minutes, or
• 80°C for 10 minutes
• Compatible with heat-sensitive substrates

Chemical & Technical Information

Applications

1. Environmental & Chemical Sensors

Used extensively for:

• Heavy metal detection in water
• Multi-analyte electrochemical sensing
• Detection of dissolved oxygen, pH, anions, and pollutants

2. Biomedical & Diagnostic Devices

• Point-of-care disposable sensors
• Potentiometric glucose and metabolite dipstick sensors
• Electrochemical biosensors

3. Printed Electronic Devices

• Ag/AgCl reference electrode tracks
• Flexible circuit printing
• Disposable test strips
• Lab-on-chip systems

4. Research & Academic Applications

Cited in numerous peer-reviewed studies, including:

• Environmental remediation sensors (Palisoc et al., 2021)
• Oxygen gas detection in RT ionic liquids (Lee et al., 2017)
• Cosmetic analyte quantification sensors (Charoenkitamorn et al., 2022)
• Urine glucose detection systems (Caldara et al., 2023)
• Multi-analyte electrochemical detection platforms (Kunpatee et al., 2020)

Processing & Handling

Screen-Printing Guidelines

• Use polyester mesh (156–230 tpi)
• Avoid stainless steel mesh (corrosive reaction possible)
• Use plastic palette knives, not metal

Drying Conditions

• 60°C for 30 minutes
• or 80°C for 10 minutes

Compatible Substrates

• Polyester
• PVC
• Polycarbonate
• Alumina

Ordering Information

Sigma-Aldrich™ Ag/AgCl (60/40) Screen-Printing Paste is a premium conductive reference electrode material optimized for electrochemical sensors, diagnostics, environmental monitoring, and printed electronic devices. Its high stability, excellent conductivity, and printability make it a trusted choice for research labs and manufacturing environments requiring dependable Ag/AgCl electrode performance.