Lab Supplies

A 4-way stopcock allows for 360 degrees of rotation and has the states (shown below) for each of the four available positions. A 3-way stopcock has only three positions and has the first three states shown below.

In the first state, liquid flows between points A and B.
In the second, it flows between points A and C.
In the third, it flows between points B and C.
In the fourth state (4-way only), it flows between all three points.

While they are sold in the popular kit 14011, they are also sold separately:

• 14035-10–4-way Stopcock...more

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...more

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
• ...more

The physical properties of glass depend upon the chemical composition of the glass, as well as how the glass was manufactured. Glass has no set melting point, but four temperatures are of primary importance when discussing glass production.

• Working Point - This is temperature that the glass is soft enough to work. At this temperature, the glass viscosity is 10⁴ poises.
• Softening Point - At this temperature, glass deforms easily, even by forces of gravity. The glass viscosity is 10^7.6 poises.
• Annealing Point - When glass reaches the annealing point and remains for a few minutes, many of the internal stresses of the glass formation are obviated. During the annealing process, the glass is heated to the annealing temperature and then allowed to cool at a controlled rate. Glass that is not annealed is prone to crack or shatter with minor temperature fluctuations...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...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...more

Choosing the right parts for your application is critical. Below you will find a table comparing many common parts to help you determine just what you need.

Cables

Specially designed tips as small as 36 gauge (110 micron OD) are offered in both blunt and beveled styles. Our studies have shown that these tips will cause less trauma to the tissue than any other form of micro syringe currently in use. NanoFil has a unique coupling mechanism that allows many different forms of small tubing and tips to be coupled with the syringe barrel.

Direct Microinjection by Hand

This is the simplest and most economical way to inject. Any of our tips can be inserted directly into the NanoFil syringe. Even the SilFlex tubing can be inserted to switch from hand injection to the other methods listed below. The limitation of this method is the difficulty...more