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Suction electrodes are used with muscle research systems to record the action potentials from the stretch receptors at the same time that the length and tension of the muscle are recorded.

 Materials

• soldering iron with solder
• wire strippers
• wooden-handled dissecting pin
• alcohol burner
• can or tube of contact or plastic cement
• fine flat file
• emery cloth
• electrical tape
• popsicle stick
• two pieces of chlorided silver wire (0.005” dia, 5” long)
  (See Chloriding Silver Wire.)
• three feet of shielded, two-conductor, insulated cable
• three color-codedconnectors that will mate to the connectors on the input cable for the amplifier
• three feet of flexible plastic tubing (20 gauge Tygon or PE 100)
• 18-gauge needle
• 3-way stop cock
• 3cc syringe
• 1cc tuberculin syringe
• glass micropipette tip

Procedure

1. The connectors and electrodes need to be attached to the ends of the shielded, two-conductor cable. Take one end of the cable and carefully strip 5 inches of insulation off the end.
   NOTE: Minimize the number...more

An amplifier, in simplest terms, is an electronic device that magnifies an input signal. However, the way an amplifier is designed to handle noise and bandwidth limitations greatly affects the quality and sustainability of the final output signal.

Defining Terms

To knowledgeably discuss amplifiers, let’s define a few terms.

• Gain – The gain is the multiplier defining how much the amplitude of an input signal is increased. A signal with an X1 gain is not amplified. An X10 gain produces an output signal ten times greater than the input signal.
• Noise – Any unwanted signal fluctuations are called noise. While noise can also result from external sources, for the purpose of this discussion, we are primarily concerned with the noise resulting from the inner workings of the electronic device, our amplifier. This intrinsic noise is called shot (or schott) noise.
• Signal to Noise Ratio (SNR) – The ratio of the output signal to the noise of the amplifier is called the signal to noise ratio. The smaller...more

Use the table below to compare WPI and Bovie part numbers.

A New Generation of Fiber Optic Oxygen Sensors Based on Luminescence Lifetime

Oxygen measurement is simpler than ever. Just stick a disposable, oxygen-sensitive "spot" to the inside of a flask, beaker, test tube or bottle, and fill the container 

with the solution to be tested. Then, on the outside of the glass container, hold the fiber optic wand close to the spot to take a reading. As the spot reacts with oxygen, it gives off light, which is measured with the fiber optic wand. This ingenious system is highly accurate and affordable. Two different units (which use the same operating principles are available: OXY-MINI and OXY-MICRO. 

The OXY-MINI system is optimized for process control and biotechnology applications. The OXY-MICRO is designed for biological research applications including implanting into tissues, cell cultures, profiling of biofilms and sediment related bioassays. The measurement principle of the sensor system is based on the detection of oxygen concentration as a function...more

• Flexible Teflon microprobes are used for implantation in tissue, in spectrophotometer cuvettes, rectally in neonatal mice, in water baths, PCR thermal cyclers, etc.
• Animal rectal temperatures during surgical procedures and pyrogen testing.
• Skin temperature measurement during exercise physiology studies.

When precise temperature measurements are required, WPI can provide you with a very accurate monitor and thermocouple microprobes. WPI monitors have both resolution and accuracy of 0.1°C in the 0-50°C range and are traceable to NIST standards, whereas, other competitive electronic thermometers have an accuracy that is usually to 0.5°C or worse. Furthermore, all our type T clinical probes are guaranteed accurate to 0.1°C, due to our stringent wire standards. These are five times more accurate than competitive probes made with regular “Special Limits” wire.

Probe Sterilization Methods:

The needle microprobes and animal rectal probes are all designed to withstand sterilization by ETO gas...more

You can use the PZMIV stereo microscope with a stereotaxic frame as shown in the image below. This setup shows a PZMIV-BS. The U-frame Base Plate (502045) is shown, but most stereotaxic frames can be used in this way. Choose a stereo microscope objective that allows you plenty of room to work. For example, the 0.5X objective has 187mm working distance, or the 0.32X objective has 296mm working distance. You could also add a Z-LITE-Z186 illuminator. If necessary, use a 5 to 10 lb.counter weight on the boom stand base to prevent the microscope from tipping.

More Info

WPI offers a range of isolators and stimulators. Use the chart below to find the components that are compatible.

See Selection

EVOM was the first instrument designed to perform routine Trans Epithelial Electrical Resistance (TEER) measurement in tissue culture research. EVOM2 is the next generation, redesigned for greater usability.

The EVOM2 sports the following features:

Types

It is common for a researcher to attach a camera to a microscope. Three types of cameras are available, and two are suitable for microscopy work:

• Television (Direct video)
  • 4:3 old style video, NTSC, PAL, 480i
  • 16:9 HDTV (DVI 1.0 compliant), 720P
• Computer capture
  • USB connection
  • Firewire connection
• Commercial cameras
  • Fixed lens cameras
  • SLR cameras

First, determine what you want to do:

• Capture images
• View live video

The cameras that do both are more expensive. Lower cost options capable of live view and image capture usually are capable of capturing fewer frames per second.

Television Style Cameras

Television style cameras send live video images to a television set. They can use the old 4:3 (boxy) format or the new 16:9 cinematic format. These cameras do not come with software, nor do they connect to a computer without adding a special interface to the computer. This image can be recorded by DVRs or by adding a video input and capture card to your computer. These cameras can record video...more

Dri-Ref™ reference electrodes were developed by WPI to have extremely low electrolyte leakage properties, hence the name “Dri-Ref.” In addition to this key feature, these electrodes exhibit stable and reproducible potential and low resistance. Stored in KCl when not in use, they have a long life expectancy. Low leakage is achieved by using KONBO™, a product combining modern ceramic and conductive polymer technology, as the liquid junction. Electrode resistance is low, an important consideration when making low-noise measurements.

Although the internal filling solution contains KCI, the low fluid leakage means Dri-Ref may be used in combination with ion selective electrodes, including those for K⁺ and Cl^-, without significant contamination from the reference electrode.

The Dri-Ref electrodes are chemically resistant to strong acids and alkalines. Dri-Ref electrodes are not suitable for use in organic solvents. In addition, the long, thin FLEXREF may be easily manipulated to accommodate...more