PourBoy® 4 Sterile Media Dispenser, incl. Pump-Tubing Set

PB4:  $918.92 - In Stock

Power Options

Pumping Speed

Variable Speed

This new device is so good, you can actually get excited about pouring Petri dishes. We periodically ask labs for their "wish lists", and on more than one occasion, researchers have said, "A good, inexpensive, reliable sterile media dispenser." Most devices on the market are either expensive, unreliable peristaltic pumps, or expensive unreliable motor-driven, syringe-based pumps.

     At Tritech Research, we designed a system combining simple, yet elegant, foot pedal controlled electronic dispensing circuitry with an inexpensive, detachable, miniature, high-tech electromagnetic pump that is easy to sterilize to make the PourBoy 4.  It can still be sterilized with alcohol, hydrogen peroxide, and hot water.  See our Extra Pump-Tubing set (PB4-PTS) product description for more details. The standard Single-speed model dispenses at a rate of approx. 3 mL / sec. The Variable Speed option allows for slower rates than this. For higher flow rates, we have added a High Speed pump option. This higher-capacity pump runs at about 12ml/sec, and it is available with a variable speed option as well.

Great new features on the PourBoy® 4 include:
  • easily user-calibrated to accurately deliver volumes from 0.1 to 999.0 mL
  • user-settable pause interval from 0.1 to 999 seconds between each dispensing operation
  • user memory to store common dispensing operations, i.e different Petri dish sizes
  • microprocessor-controlled accuracy, and a fully digital, wipe-to-clean membrane keypad

Note: The PourBoy® 4 pumps are designed to pump smooth liquids, like aqueous solutions, hot molten agar, and oils, but not particulate materials like grits, grains, pastes, etc.  For example, it is great for dispensing hot agar growth media into Petri dishes and dispensing sterile cell culture media, but not suitable for dispensing oatmeal or Drosohila food.  The PourBoy 4 is a new improved replacement for the PourBoy III.  It uses less expensive pumps yet they are less prone to jamming, and it has built-in temperature compensation for improved calibration accuracy over a wide range of media temperatures.  The PourBoy 4 is the preferred device for C. elegans labs that need to dispense NGM medium and pour thousands of Petri dishes per week. Here is a recent publication referencing the PB4:

Re-replication of a Centromere Induces Chromosomal Instability and Aneuploidy. Stacey L. Hanlon, Joachim J. Li. PLOS Genetics. April 22, 2015.

Feel free to contact us for your special dispensing needs, such as integration with computer-controlled multichannel dispensers.  If you can think of it, we can probably make it!

Approximate specifications of the PourBoy IV:

Height: 14cm (5.5")
Width: 15.5cm (6")
Depth: 20cm (8")
Weight: 1kg (2.2 lbs)
Pumping rate, full speed, Standard Pump, normal conditions: 3ml / sec
Pumping rate, full speed, High Speed Pump, normal conditions: 12ml / sec


Q: I am having media contamination problems when using my PourBoy. How can I sterilize the pump tubing set?
A: There is a very easy and effective way to sterilize the pump-tubing set - you can recirculate hydrogen peroxide through it. The "drugstore grade" 2% hydrogen peroxide works fine for this. While alcohol is pretty good at killing most bacteria, hydrogen peroxide is very effective at killing both bacteria and fungus, yet it is much more compatible with the internal components of the pump than bleach (which is not recommended). Of course, it is also important to do negative controls when looking for the source of contamination. Hopefully, you already know that there is no contamination already present in the "sterilized" media or the Petri dishes. The next time that you pour a batch plates you could manually pour a few using a sterile pipette to make sure that the source of the contamination is not upstream from the PourBoy.

Q: How precise and consistent is the PourBoy?
A: The PourBoy can deliver liquid volumes precisely from 0.1 mL to 999.0 mL. The precision is controlled by a microprocessor, which ensures consistency of aliquots. Precision using the standard pump is typically within 2%. Reproducibility can be affected by hydrostatic pressure - the difference in height between the input medium and the output dispensing tube. Do what you can to minimize changes in this height over the course of dispensing. This difference is more pronounced with the High Speed pump than the Standard pump.

Q: Do you have to hit the foot pedal for each dispensing operation?
A: The PourBoy has two dispensing modes, Manual and Automatic. In Manual Mode, the set volume is dispensed each time the foot pedal is pressed. In Automatic Mode, you can set the pause interval between deliveries of media, and press the foot-pedal once to start and once to stop the cycle.

Q: What is the difference between a Standard and a High Speed PourBoy?
A: The High Speed PourBoy is capable of a 5x faster rate of media flow than the standard version. The pump can dispense liquids at a rate of ~800ml/minute vs. ~180ml/min. Both versions have a variable speed option. Without the variable speed option, the pump always runs at its maximum speed; the variable speed allows it to slow down to flow rates below maximum.

Q: What happens if the PourBoy sterile media dispenser ends up clogged?
A: We ALWAYS recommend that you purchase an extra of pump-tubing set (PB4-PTS) with your PourBoy sterile media dispenser in case you encounter any problems with the pump or tubing getting clogged. This way, you can quickly change out the pump-tubing set, continue working, and worry about cleaning it later.

Q: Does the PB4 Media Dispenser need to be used in a sterile culture hood (for pouring plates)?
A: It is always best to pour sterile media in the hood to reduce the chance that mold spores or bacteria or dust will fall into your media. We recommend avoiding contamination at all costs! Also, if your hood has laminar airflow, that will also help to evaporate any condensation that forms on the Petri dish lids and to cool and gel the plates more quickly.

Q: After I pour agar in the plates, how long should I leave them exposed to the air before I cover them with the lids?
A: To avoid contamination, it's best not to wait at all. Before pouring the plates, if you allow the media to cool (while stirring on a hot plate with a magnetic stirring bar) to about 45-50°C, then you can close the dishes immediately. The resulting condensation should evaporate after several hours. We recommend first forming a stack of plates, for example, 5 plates tall (or 10 plates if you have good balancing skills). Then, we suggest lifting the top 4 plates, plus the lid from the bottom plate and shooting the media into the bottom plate. Next, lower the stack, putting the lid back on the bottom plate, and lift the top 3 plates plus the lid from the second-to-the-bottom plate, and shoot media into that 2nd plate, etc. It is important not to move the plates around after you have poured them and before they fully gel, to avoid a messy surface. You'll get the hang of it in no time!

Q: How can I avoid contamination of the plates and gelling media inside the PourBoy pump?
A: First, always follow the instructions that come with the PourBoy and autoclave 2 bottles of distilled water along with your media. Run one bottle of hot water through the PourBoy before you pour your media to preheat the tubing and pump and wash out / sterilize any contamination. Run the second bottle through the PourBoy *immediately* after you pour the last plate to wash out any media before it can gel in the system.

If you have a small emergency where you have to stop pouring plates for a few minutes, redirect the dispensing tube back into your flask of medium and use the automatic mode to keep recirculating the medium through the tubing so that it doesn't cool and gel in the tubing and pump! Even 1 minute of stationary medium could cause an unpleasant gelling problem.

Q: What is a recommended practice for pouring plates?
A: We recommend holding the output tube in your hand and aiming it into the dishes at a 30-45 degree angle. If you find that the stream is not smooth enough or dripping at the end of each dispensing operation, you could insert a piece of smooth glass or plastic tubing at the end of the output tube to act as a nozzle. Do make sure that the nozzle is still being sterilized with the same procedure you use on the rest of the tubing.

Q: Would you recommend the standard pump or the high-speed pump for pouring 100mm diameter petri dishes?
A: 100 mm diameter dishes will typically get filled half-way up with about 40 ml of agar-based media. The standard pump will dispense 40 ml in about 12-15 seconds. At this rate, it will be very tame and accurate within 1 - 2%. The high speed pump will dispense 40 ml in about 3 seconds. At this rate, it will come out with some force (but you should be able to avoid spattering by aiming properly) and will be accurate to about 5%. The variability is caused by hydrostatic pressure. When the height of the agar media surface is higher than the height of the tubing pointed at the dish, the flow through the pump is faster. The flow will become slower as the media is depleted, thus decreasing the height difference between the media surface and the dishes. The high speed pump is more sensitive to this effect than the standard pump. Having the media in a wider flask reduces the height difference as compared to having it dispensed from a tall, narrow flask. If you were dispensing 100 ml at a time, we would definitely recommend the high speed pump to save time. If you are pouring 15 ml or less into 60 mm petri dishes or smaller, we would recommend the standard pump for a tamer pour speed and higher accuracy.

Q: If I order the high speed model of the PB4, can I still adjust the speeds to slower rates?
A: Yes, as long as you order the variable pump speed option, you can adjust the speed from anywhere between about 1ml/sec to 12 ml/sec. It is also possible to switch back and forth between the high speed pumps and standard pumps by swapping out the pump and coil yourself. However, if you order the standard model, it will require a factory upgrade if you want to use the high speed pumps later.

Q: How can I prevent the tubing to stay submerged in the media instead of floating up to the top when using the High Speed PB4?
A: The extra vibration from the high speed pump could be causing the weight of the tubing outside the flask to pull on the tubing inside the flask. You can try taping the tube in place or shoving something against it at the neck of the flask to see if that solves the problem.

Q: Will I need a handle of some kind or is the tubing cool to the touch when dispensing molten agar?
A: The silicone rubber tubing provides a bit of insulation, so you probably will not need a handle when touching the tubing. You could use lab gloves which also will provide a layer of insulation.

Q: How can I attach a sterile syringe to the PB4 tubing?
A: To make a piercing adapter tip to inject large volumes, I suggest a large-bore needle / cannula with an O.D. of slightly over 1/8 inch so that it fits tightly inside the PB4's output tube. If it were for much smaller volumes than 40ml, you could use a 1cc syringe body with slip-tip output as an adapter for standard luer-lok / slip-tip needles that are available up to about 16 gauge.

Q: Which replacement parts would you recommend for the PB4 for extended use?
A: The PourBoy base unit and coil have no moving parts (except the push buttons) and are generally very robust. The item with the most variability and sensitivity is the pump cartridge because it has small springs and small apertures that could get clogged with gelled agar or particulates. For some people they last years, and for others they might last less than a year. Over the years, a few people have also managed to damage the foot pedal or the plug / receptacle for it.

† These are our list prices. If you are paying with an Institutional Purchase Order or by check, you qualify for a 7.5% discount. Click here to change your payment method and see the lower prices.