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NOTE: A heat treated tip is ideal for penetrating tough membranes. (It is not recommended for chronic implantation.) This process is performed using a microforge in which the heating element is positioned in close proximity to the tip in order to melt the Parylene-C distal to the exposed metal. It provides a smooth transition and produces better adherence of the Parylene-C to the metal. Both the KT and non-KT electrodes are heat-treatable. The heat treatment is applied only to the parylene coating. The heat melts the parylene so it feathers down close to the shank near where the tip is exposed. This removes the abrupt edge where the parylene has been removed to create the tip exposure. The purpose is to prevent the parylene from delaminating from the electrode during implantation into tissue which could catch on the edge. Heat treatment does not work well in chronic applications, because the feather edge is susceptible to fluid intrusion overtime, which will alter the impedance characteristics...more

Profile A Metal Microelectrodes

Introductory Assortments

Each of these assortment kits includes electrodes with different impedance within each style. Use an assortment kit to determine which electrode you need for your experiment. Each box includes the electrodes listed. There are no mix and match assortment kits.

Profile A

Profile B

Profile C

Assortments Profile A Comparison Chart 

Assortments Profile B Comparison Chart 

Assortments Profile C Comparison Chart 

Concentric Electrodes*

Profile B

Eliminate the cost and trouble of making your own micropipettes — WPI can quickly supply your need for consistently sized pre-pulled glass micropipettes for injection of dyes or proteins into cells, oocytes and for many other biomedical laboratory applications. Tip diameters (ID) range from 0.1 to 10 micrometers. Micropipettes are available as plain shank or with luer fittings.

• Schott Duran borosilicate glass
• 0.5 micrometer and smaller ID micropipettes include an internal glass fiber for easy filling
• Tip inner diameter tolerance ±20%
• Short taper yields high strength
• Nominal length ≈ 50 mm
• OD:ID = 1.33:1
• Standard capillary outer diameters are 1.0 mm (thin-wall) or 1.14 mm
• Every pipette individually tested and inspected
• Vacuum packed

Silanized Tips (Luer Shank)

Silanization waterproofs the glass to retard water when inserting into cell. This will not let the outside fluid run down the pipette and get inside so easily.

WPI offers an array of metal microelectrodes. In this guide, we will look at introductory assortments, concentric electrodes, profile A, profile B and profile C electrodes. For basic information on these types of metal electrodes, see the Metal Microelectrode Basics page. Links to these related posts appear below this article.

Eligoy Steel is a *Cobalt/chromium/nickel alloy.

Deciphering Part Numbers

Luer kits contain many plastic parts made of a variety of materials. A common question is how to sterilize these parts. Common sterilizing methods include:

• EtO (gas)–a chemical steriliant small enough to penetrate the microbial cells that destroying nuclear cell components
• 70/30 Alcohol
• Cidex (Activated Dialdehyde solution)
• Autoclaving (wet 121°C, 15PSI for 30 minutes)–Before autoclaving, verify that the caps are properly loosened or removed to prevent any accidental implosion. Carefully clean the items with distilled water before autoclaving, because some chemicals that are inert on plastic resins at room temperature causes deterioration at high temperatures.

Can the Luer Kits be Autoclaved?

We offer to following luer kits. This table shows the materials used in each kit and whether or not the plastic parts are autoclavable.

What Materials are Autoclavable?

This table shows a...more

WPI offers a variety of precious metals and wire. The table below compares the specifications of the various wires. The following hints are offered to help you understand the part number codes and choose the wire you need:

• Micro coaxial cables (MAXxxxx) are ideal for microelectrode fabrication and construction of similar research tools. The dual shielding eliminates electrical interference caused by radio frequencies (RF), electrostatic and microphonics (e.g., bending and vibration). Available with single or dual (twin) conductors.
• Thermocouple wire is for tem­per­a­ture mon­i­tor­ing. TCK3050 has a chromel/alumel pair, for use in inert or oxidizing atmosphere at 1500-1800 °F.
• Teflon-coated stainless steel (type 304) wire (SSTxxxx) is available in 25-ft and 50-ft lengths. The Teflon coating is 4µm thick.
• Carbon wire (C3005) is a single 30µm fiber of electrochemically activated car­bon. This fiber is especially useful in micro-elec­tro­chem­i­cal experiments.
• Carbon filament wire (...more

WPI’s microelectrode holder-half-cells couple fluid-filled glass micropipettes to high input impedance amplifiers. A Ag/AgCl pellet (or a silver wire) molded into the holder body provides stable potential. Electrical connection is made via male 2mm pins or female 2mm sockets. The pipette may be mounted axially or at right angles to the holder. Pipettes are held with screw-caps or rubber gaskets (without caps). Filling WPI microelectrode holders with electrolytes containing chloride results in stable electrode potential. Suitable electrolytes include KCl, NaCl andCaCl₂. Holders are supplied for standard WPI single capillary tubing of 1.0, 1.2, 1.5 and 2.0mm outside diameters. (Call WPI regarding custom designs for other glass diameters.) The holder style you select will depend on your experimental application, space, and instrumentation.

Hints for selecting and ordering micropipette holders

1. Determine the required electrical connection on the holder. For example, if you wish to connect...more