FAQ

Firstly, refer to the manual to verify your understanding of how the equipment is supposed to work. If you still think there is a problem, use the test dummy membrane to isolate the instrument from the chamber system. If the problem is still there then there is likely an electrical fault in the equipment. Please contact Physiologic Instruments and talk to one of our friendly staff members to help diagnose the problem and recommend a process to remedy the defect.  

Yes, you will need a computer running the Windows operating system (OS). What type depends on which of our Acquire and Analyze hardware system you have purchased. One system requires a parallel port set to ECP or EPP mode in the BIOS and operating under the Windows XP, Vista, 7, 8, 8.1 32 bit operating system. The latest version uses a USB 2.0 interface and can run on any of the Windows operating systems including the Windows 10 64 bit OS. 

From three to eight feet depending on the equipment you order (examples: a single channel VCC600 or 2-channel VCC MC2 requires only about 3 feet; a 6 or 8-channel system using the VCC MC6 or VCC MC8 with data acquisition and computer requires a minimum of 5 feet, but 6-8 feet is more comfortable). We have found it important to mount the instruments on a shelf above and behind the Ussing chamber system to prevent problems due to spilling of saline solutions onto the electronics. For example, see (LINK to pic)

OptiGain control is an option for our multichannel voltage/current clamps that enables changing internal jumper selections from a set of external switches. All of our voltage/current clamps were designed for use with a wide variety of tissues by providing internal jumpers to select current gain and fluid resistance compensation range (3 jumpers per channel). This works well for labs predominantly using only one tissue type; however, much more frequently now labs switch types and sizes of tissues. For example, they may use very small biopsy tissues (0.008 cm²) in the morning and then change to using cell cultures grown on Snapwell inserts (1.12 cm²) in the afternoon. Opening the instrument and manually changing all the jumpers is too laborious for this so we designed electronic switching we call Optigain to enable changing these jumpers on all channels from a set of 2 switches on the front panel. Physiologic Instruments is the only company that has this feature to enable scientists to quickly and easily optimize the electronics for use with a very wide range of epithelial tissues.

No, the equipment is fully calibrated prior to shipping and calibration should only be done by Physiologic Instruments.  The equipment has proven to be quite stable and should stay within calibration for a minimum of 3 years.  If you are concerned with the equipment’s operation or have determined that the equipment is overdue for a calibration, please contact us and we will schedule your equipment for service (requires the equipment to be shipped back to Physiologic Instruments please contact us if you need proper shipping material).

The instruments all have circuits to select the appropriate mains voltage. Before we ship the equipment, we preset all equipment for use with the specific type of electrical power at your laboratory which may be 100, 120, 220, or 240V at 50 and 60 Hz.

The EasyMount Ussing chambers were designed to be used with a wide variety of epithelial tissues and cell cultures by using a “carrier system” in which the tissue or cell culture is first mounted in a specific holder that is then slid into the chamber. Thus, by simply changing the tissue carrier, which we call a “slider”, epithelial, and some endothelial tissues, ranging in size from the very small (new born mouse trachea or insect intestine) to human nasal or intestinal biopsy, mouse or rat intestine, bovine intestine, human cornea or corneal endothelium, frog skin, bladder, etc. as well as cell cultures can all be mounted in the same chamber – only the slider has to be changed. Aperture sizes for our slider range from 0.002 to 1.27 cm²_. Please note, sliders are chamber specific and cell culture inserts can only be mounted in the P2300 chamber.

Yes. Please see answer to previous question.

First, go through the manual and test the equipment according to the testing protocol using a dummy membrane. If you are still having problems call Physiologic Instruments and a representative will help to verify the problem and will either help you fix the problem or arrange for equipment repair.

This option can be retrofitted to all VCC MC6 and VCC MC8 series instruments. It is not currently available for the VCC MC2 or VCC600.

We recommend recalibration: 1) after three years of use; 2) if you move the equipment to a new facility; or, 3) if the equipment was stored for a few years. However, if you notice that the meter displays a positive or negative integer -- is not zero when your equipment is in standby mode (i.e., at power-up), or you notice spurious data during collection you should consider sending the equipment back to Physiologic Instruments for checkout and recalibration.

Yes, we design and manufacture are own chamber equipment and have manufactured custom sliders to hold a variety of tissue samples. Please contact us directly (858 451-8845) to discuss your needs. Turn-around time for a relatively small number of tissue sliders usually ranges from 2 to 8 weeks depending on slider complexity and our workload at that time.

Yes, you can perform both bioelectric measurements (PD, Isc, Rt, Gt) concomitant with flux studies or drug permeability studies. Ion flux measurements are enhanced because the mean Isc is calculated from measurements over the entire flux period rather than, as typically done, by the average of only two values, the beginning and end currents.

As described in another FAQ specimens are mounted in our Ussing chambers using specifically designed holders that we call “sliders”. We have a wide variety of these available and can design custom sliders for your particular tissue should that be needed. Tissues that have been studied in our chambers include native epithelium as well as cell culture models from airway, nasal mucosa, intestine, stomach, taste buds, esophagus, bladder, vagina and uterus, cornea, skin and kidney. Endothelium from cornea or blood-brain barrier in culture can be studied as well.

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Physiologic Instruments has been selling Ussing Chamber systems and accompanying software for nearly 25 years.

The slider is usually made out of acrylic or delrin (acetal).  To clean the sliders you will use the same cleaning procedure as for the Ussing chambers.  Please refer to the cleaning instructions included with the manual or contact us and we will gladly send you a description.

The main consumables physiologic saline solutions, test agents, electrode tips (sold in bags of 100, P2023-100) that must be filled with agar and saline, permeable membrane supports (Corning, Millipore, or Nunc) if you are using cell cultures, and after considerable use, you will likely need to recondition or replace the voltage and current electrodes (P2020-S, see instruction sheet).

Sliders are interchangeable only with a chamber that whose part number begins with the same first 3 characters as the chamber (e.g., slider p/n P23xx when P23 indicates compatibility with the P2300 chamber). Physiologic Instruments current makes three types of EasyMount Ussing chambers that work with a variety of tissue holders and permeable membrane support holders referred to as sliders. The three models are interchangeable with respect to the EasyMount chamber stand. These models are:

 1) The P2300 standard chamber is the most versatile. It has a working bath volume of 2.5 to 7 ml for each chamber half the chamber and handles both small 0.008 cm² and large tissue samples 1.27 cm² as well as the most popular permeable membrane supports for all cell culture  models (see P2300 slider list).

2) The P2400 is a low volume chamber having a working volume of 1.2 - 7.0 ml.  This specialized Ussing chamber is valuable for studies that include the use of rare or costly drugs. Tissue sliders for the P2400 range in aperture size from 0.002 cm² - 0.71 cm^{2 (}P2400 sliders)^.  Because it is designed for low volume, the P2400 is not compatible with cell culture inserts.

3) The P2500 chamber is designed to be used for rat or larger animal intestine. It has only one slider with an aperture of 22 mm x 5 mm (1 cm²).  This Ussing chamber increases the tissue area of rat intestine that can be studied in this Ussing system which is useful for drug perfusion and ion flux studies as well as for collecting endogenously released peptides from tissue samples.  The working volume can range from 2.5 ml to 7 ml.

Ultimately, the answer is Yes. If you purchase the equipment directly from Physiologic Instruments, Inc. then please contact us directly for any warranty issues. If you purchased from a reseller of our equipment, please contact the reseller to make a warranty claim.

Yes. The system is easily expandable to 24 or even 32 channels. Currently each set of 8 channels requires its own A&A system. We hope to have a multisystem version of the A&A system available in 2016.

Please contact us for a quote and more information on how to optimize your setup for greater throughput.  You may be eligible for a multisystem discount.

Yes, we sell directly to both domestic and international locations.  There are several benefits to buying directly from the manufacture including price, faster delivery, and direct and knowledgeable customer support. Physiologic Instruments will ship the equipment for delivery directly to your laboratory.

Note: All of our products warranties are fully covered worldwide (see warranties). 

We prefer to sell our equipment as a complete system which includes a considerable discount in price compared to à la carte. The other advantage of this is that all components in our systems are designed to connect and work together as a unit which greatly simplifies the user experience. However, we realize some customers already own components such as specific chambers or competitor’s instruments which they can’t afford to duplicate.  We are happy to work with these customers to provide components that will work with their existing equipment. Please let us know exactly what equipment you already have and what you want to accomplish, then we will recommend individual components that will work for your studies.

Yes, we offer a full installation and training package which includes installation of all the equipment, verification of equipment function, and 1½ days of training in how to operate the equipment, design and run specific protocols and analyze and export data from the software. Our training staff members have a Ph.D. in physiology and extensive experience in epithelial transport studies.

At Physiologic Instruments we pride ourselves on making the best product for the best price. We have many good friends in the research community and can’t arbitrarily give discounts to certain customers, but not others.  We keep our prices competitive and fair, but profitable enough to remain in business and support our customers for years to come.

We accept purchase orders from university, pharmaceutical or government research labs with whom we have agreed upon payment terms. Advance payment by credit card can be arranged. Credit card fees may apply. Please contact us for further information.

Many orders are “custom” so we assemble them at the time of order from components that we try to keep in stock. As such, most orders can be shipped in 1-5 weeks after receipt of order depending on their complexity. Many accessories can be shipped from stock. The time for delivery will depend on geography and the class of service you choose for shipping. If you order a custom or specialized slider for one of our Ussing chambers, the design and production process may take four to six weeks.

If you purchased our Installation and training package, then don’t do anything except to make sure you received all the boxes (e.g., 3 of 3) and keep all boxes together in a safe place – we will take care of the rest when we arrive to install the system. If you did not order the installation and training package then you will need to carefully unpack the boxes and check the contents against the packing list. Immediately report any shortages to your supplier. Fully read the operator’s manual and install the equipment accordingly. Voltage/current clamp instruments are factory calibrated; please do not make any internal adjustments without first contacting Physiologic Instruments.