Page 25 - Blog
- - April 18, 2021
by Benjamin Dubansky, PhD, Animal Physiologist/Researcher
The EVOM is a special kind of voltmeter for measuring electrical properties across a layer of cells in culture or a biological membrane. It is the most commonly used commercial system for measuring across a layer of cultured cells. We are measuring TEER (TER) - Transepithelial Electrical Resistance. The EVOM3 allows us to zoom in and measure either resistance or voltage across these membranes or cells in culture.
- - April 18, 2021
The Peri-Star Pro is a popular peristaltic pump. Here we will show you how to install the tubing in the pump head so that you can use the pump.
First, remove the tubing fixture by pressing the Locking Tab on the left side of the fixture and pulling the fixture open.
Then pull the tubing through the fixture. Make sure the tubing is straight inside the fixture with no kinks.
Remount the fixture on the pump head. The rounded notch is on the right side of the fixture, and it fits against a steel rod on the Pump Head. When the other end of the fixture is pushed into place, the locking notch will snap into place against the inside of the Locking Tab.
Turn the Adjusting Screw, if necessary, to get a smooth flow.
If you have any questions about your Peri-Star Pro, just give us a call.
- - April 18, 2021
The Peri-Star Pro is a popular peristaltic pump. Here we will show how to set the system parameters for your application.
Using the Control Knob to Navigate the Menu
Press the Control Knob to enter the setup mode in the main menu, then rotate the Control Knob to toggle between the four functions. Press the Control Knob again when you get to System Setting. Turning the Control Knob toggles between the submenu items.
Define System Parameters
- Tubing ID is the first submenu. To change tubing inside diameter, click the Control Knob. After clicking, a list of tubing IDs appears. Turn to the desired tubing ID and click the Control Knob to select it.
- Test Time sets the flow time when performing a calibration. To change the time, click the Control Knob on this submenu item, then turn the Control Knob to the desired test time. Click the Control Knob to select it.
- Remote enables or disables the external remote-control module. When this menu option is enabled, you may use an external remote-control...more
- - April 08, 2021
Let’s look at the PUL-1000, a microprocessor controlled, four-stage, horizontal puller for making glass micropipettes or microelectrodes. Here we will examine the design of the unit.
Tempered Glass Lid
For safety, the lid should be closed whenever you are pulling glass or moving the unit.
Capillary Glass Clamp Pads
These two silicone clamp pads securely hold the glass when you are pulling pipettes. Check the glass OD and install appropriate pads accordingly.
Heating Filament
The PUL-1000 comes with a circular platinum/iridium box filament, which may be easily replaced with a 2.5 x 2.5 mm box filament (WPI #13834).
Glass Groove
Slide a single piece of capillary glass into the groove from one side or the other. The groove helps line up the glass to slide easily through the filament and hold it in the proper position during pulling.
Carriage
The carriage should move freely when the clamps are unlocked. It slides apart as the glass is pulled. Then, you can manually slide the two ends...more
- - April 07, 2021
Vernier scales can be used on microscopes, stereotaxic frames and micromanipulators. The vernier scale was invented by French mathematician Pierre Vernier in 1631 as an upgrade on Pedro Nunes' measurement system for precision astrolobes. With a main scale and a sliding secondary scale, a vernier is used for making precise measurements.
How a Vernier Scale Works
The vernier scale is marked with divisions slightly smaller than the divisions of the main scale. For example, a vernier scale could have 11 markings for every 10 on the main scale. That's 10 divisions on the vernier scale for every 9 on the main scale. This means that the vernier divisions are each 90% of the main scale divisions. In this case, the 0-line and the 10-line on the vernier could pair up with marks on the main scale, but none of the other divisions on the vernier would match a line of the main scale. For example, the 0 and 10-lines of the vernier scale could pair up with the 0 and 9-lines on the main scale...more
- - April 05, 2021
A peristaltic pump is a popular appliance in any laboratory. Here you will find some tips for choosing the correct tubing to use for your application with your Peri-Star Pro peristaltic pump.
Size (ID) of Tubing
In a peristaltic pump, the flow rate is determined by both the size of the tubing and the rotor speed. WPI provides two sizes of silicone tubing:
- 1/16-inch ID tubing for low flow rate at 0.2-18mL/min.
- 1/4-inch ID tubing for high flow rate at 3.5-280mL/min.
Types of Tubing
- Silicone tubing has a long service life and good chemical compatibility for aqueous and many organic solvents.
- Fluoroelastomer tubing should be used when pumping halogenated solvents.
- Vinyl tubing is used only with chemically compatible solvents.
If you have any questions about tubing for your Peri-Star Pro, just give us a call.
- - April 05, 2021
When using the Peri-Star Pro, solutions pumped should never come into contact with the pump. Here we will give you some guidelines for operating your peristaltic pump in a way that is safe for both the laboratory personnel and for the machinery.
Some solvents can permanently damage a peristaltic pump. The following rules are recommended to avoid leakage when running your Peri-Star Pro peristaltic pump.
- Follow safety rules when handling aggressive solvents.
- Pull a fresh section of tubing into the tubing fixtures regularly. If the pump gets heavy use, do this weekly.
- A fresh section of tubing should be pulled through the pump rollers before the pump is left to run unattended.
- Change the tubing immediately, if it is visibly worn.
- Be sure the tubing used is compatible with the solution being pumped.
- Always turn off the power and unplug the power cord when changing the tubing.
If you have any questions about your Peri-Star Pro, just give us a call.
- - April 05, 2021
A peristaltic pump is a type of positive displacement pump used for pumping a variety of fluids, particularly clean, sterile or aggressive fluids. Here are five reasons to choose the Peri-Star Pro peristaltic pump.
The fluid contacts only the interior of the flexible tube and thus avoids contamination from the pump or damage to the pump. This makes it easy to maintain and clean.
The Peri-Star Pro peristaltic pump provides accurate and precise fluid delivery. It can run at flow rates from 0.1mL/min. to 280mL/min. with better than 0.5% accuracy.
Peri-Star Pro has a backlit digital LCD display and a water-resistant membrane keypad.
A unique planetary gear design with eight actively driven rollers (four rollers in the higher flow rate model), together with independent fine adjustment of tubing compression, increases flow accuracy and prolongs tubing life.
The user-friendly interface makes the setup, calibration and operation easy and problem-free.
If you have any questions about the Peri-Star...more
- - March 04, 2021
WPI’s disposable scalpels come in many styles and are ideal for students, researchers, and crafters. Here we will describe some of the uses for these popular blades.
Scalpel blades come in a variety of shapes so that you can choose the ones best suited to your application.
The #10 blade is a commonly used blade for surgical applications. It is used for making large incisions through skin and subcutaneous tissues. It is similar to the #20 blade, which is somewhat larger. The #20 blade is used for larger incisions through thicker tissues or for dissection of the soft tissues in larger animals.
Blades #10, 15, 20, 21, 22, 23 and 24 are all curved and said to have a "belly." They are all used for making incisions. The sharpest area on these blades is the apex of curve at the belly. This is the spot on the blade which is used for making the incision. Since the #15 is the smallest of these belly blades, it is often used for small animal surgery where short, precise incisions are...more
- - February 24, 2021
NanoFil™ is a unique low volume syringe developed for improved microinjection in mice and other small animals. RPE and IO kits are specially designed for “hands-free” and oil-free sub-microliter injection. Originally developed for retinal pigment epithelium and intraocular injection, they can also be used for other applications.
The NanoFil syringe system utilizes a seal system that is based on a 0.46 mm shank diameter. Any needle or tubing with an outside diameter of 0.46 mm should fit the NanoFil’s seal system. Here is how to install your needle in a way that prevents damage to the gasket and keeps your needles straight.
PRO TIP: Always use surgical gloves to prevent the oils from your skin from affecting the needle or the gasket.
- To change or install a needle, loosen the screw cap by turning it counterclockwise to release the compression of the seal. If there is a needle in place, it should pull out easily.
- Remove the screw cap and the gasket from the syringe.
- Install...more
- To change or install a needle, loosen the screw cap by turning it counterclockwise to release the compression of the seal. If there is a needle in place, it should pull out easily.
