Q&A

The liquid aspirated may be affected by hydrostatic pressure, therefore, when using long tips (#801 tip (250μL), #805 tip (1200μL)) with the same pipettor, it is necessary to adjust the pipettor scale according to the height of liquid aspirated.

The total length of the tip can be found in the general catalog PDF or online shop.

“””#503 is of the Eppendorf type, while #703 is of the Gilson type, and their outer appearance differs. However, since the inner diameter of the fitting part is the same, both can be used with the same pipette. The system racks are also designed to be interchangeable.”

We offer empty racks for each model separately. Please check the comprehensive catalog PDF or online shop for empty rack availability.

The polycarbonate (transparent) type is suitable for repeated autoclaving. The polypropylene (semi-transparent) type is more affordable, but it may experience some fitting issues with exchange plates due to susceptibility to heat deformation.

The compatibility with multi-channel pipettes from various manufacturers has been verified, but there are some models where compatibility has not been confirmed. If you specify the suction volume range, we can provide samples of rack tips for testing with your pipette before purchase. We recommend conducting a pre-purchase test with your pipette.

The #804C is the successor model. The dimensions of the tip are all the same, but now they come with improved graduations.

#204 and #207 have graduations at 2 and 10μL. #705 has graduations at 20, 50, and 100μL. #706 has graduations at 200, 500, and 1000μL. #805 has graduations at 50, 100, 200, 500, 800, and 1000μL. You can also check this information in the general catalog PDF or online shop.

We use polyethylene (PE). The heat resistance temperature is up to 80°C, so autoclaving is not possible.

Refill plates come with only the tips set on the plate, without racks (base and lid). They are intended for refilling after using the system rack. Both refill plates and system racks are individually packaged.

Some pipettes have detachable tip ejectors (for removing tips). When attaching the removed ejector, please ensure that it is securely attached to the designated position. If the attachment position is too low, the tip will not fit snugly onto the nozzle cone.

The products with this mark on our website and in the Watson general catalog are applicable. Most of our products are applicable.

If there is uneven wear or damage to the mating part (nozzle cone), it may cause trouble. Also, if the same phenomenon is observed with other pipettes of the same model that you are using, it may indicate a batch defect in the tips. We apologize for the inconvenience, but please contact us through our website.

Filter tips are all sterilized, so we do not sell them in bulk packaging.

Unfortunately, they cannot be autoclaved. The material of the filter is polyethylene, which cannot withstand temperatures of 121°C. Therefore, we sell them all pre-sterilized using radiation.

Refill plates come with only the tips set on the plate, without racks (base and lid). They are intended for refilling after using the system rack. The case after use can also be used as an autoclave rack for non-filter tips.

The #415/ #515/ #5155/ #615/ #815/ #8155/ #915 (for shading)/ Prokeep 1.5 mL tubes have graduations at the 200 and 1000 μL positions respectively. Hyper microtubes, #715/ #7155 only, have graduations at the 500, 1000, and 1500 μL positions.

In models 131-715C, 131-7155C, 131-815C, 131-8155C, and 131-415C, we guarantee a centrifugal strength of 20,000 × G (water 1.0 mL, 15 minutes).For other microtubes, please check the PDF catalog or contact us for details.

Depending on the sample being centrifuged, it may not withstand 20,000 G due to its specific gravity or chemical resistance. Also, even at the same 20,000 G, extended centrifugation times may lead to damage. (For example, subjecting 1 mL of high-concentration ethanol/isopropyl alcohol to 20,000 G for 30 minutes can result in fine cracks, and in the worst case, breakage has been confirmed.)

While some expansion and contraction may occur during autoclaving, deformation or discoloration is rare. Please verify the water level, temperature settings, and actual temperature during operation of your autoclave. If the autoclave is operating properly and issues with the tubes recur, it may indicate a batch defect in the tubes. We apologize for the inconvenience, but please contact us via the inquiry form.

We do not guarantee that the caps will remain closed during heat treatment of the tubes. Please use dedicated tools. Depending on the reactants, there is a risk of tube rupture due to sealing the lid.

We have sterilized tubes available for the following product numbers. All are divided into sets of 10 with the caps already opened.※Excluding 131-015US (lidless microtubes).
※Sterilized tubes
131-715CS-N・131-7155CS-N・132-620CS-N・131-815CS-N・131-8155CS-N・131-415CS-N・131-615CS-N・131-515CS-N・131-5155CS-N・131-015US・130-806CS-N

We use virgin polypropylene.

Please do not use in the liquid phase under any circumstances. We do not guarantee storage in the liquid phase for quality and safety management. Please store in the gas phase.

Watson screwcap tubes are tested under the following conditions. If your centrifuge comes with a dedicated adapter, please be sure to use it in conjunction.
・For 0.5 mL tubes: 17,000 × G (0.5 mL of water for 15 minutes)
・For 1.5 mL tubes: 20,000 × G (1.0 mL of water for 15 minutes)
・For 2.0 mL tubes: 20,000 × G (1.5 mL of water for 15 minutes)

Please start using within one year from the manufacturing date.

Do not store the bag open and unused. Once the bag is opened, the sterilization effect is lost. Be sure to open it in a clean bench or safety cabinet just before use.

Please refer to our verification results table for reference. The storage temperature also affects the expiration date, so we recommend lower temperatures for those considering long-term storage.
(ReferenceＵＲＬ：https://watsonbiolab.com/products/pvp/livingsituation_e.pdf）

In general, lowering the temperature reduces the metabolic rate of both aerobic and anaerobic bacteria. Reduced metabolism decreases the consumption of biochemical energy (ATP, glucose, etc.) in bacterial cells, thereby enabling long-term preservation of the bacteria.

One of the reasons for the higher survival rate is also the original purpose of oxygen absorbers, which is ‘mold prevention.’ Inadequate storage conditions, such as storing in a high humidity environment, may lead to the growth of mold on the filter paper, which readily absorbs moisture from the air. In such cases, the stored strains may perish. Additionally, the use of oxygen absorbers reduces aerobic respiration metabolism in aerobic bacteria. Reduced metabolism decreases the consumption of biochemical energy (ATP, glucose, etc.) in bacterial cells, thereby enabling long-term preservation of the bacteria. Therefore, the survival rate increases when oxygen absorbers are used, especially for aerobic bacteria. (Metabolism does not decrease for anaerobic bacteria.)

Storing at -80°C may cause the adhesive of the protective seal on the plate to malfunction. Please avoid storing below -20°C and consider stacking with seal surfaces facing each other for storage. Storing with seal surfaces facing each other prevents curling of the protective seal.

This validation data is obtained using indigenous E. coli commonly used in food quality testing and is not recombinant.※ Recombinant E. coli, genetic engineering strains, host E. coli, and other terms may vary depending on the individual, but they all refer to the same thing.

Autoclaving may cause some expansion and contraction, but the dimensions of each rack are as follows:
For 201/207: W 118 x D 82 x H 64 (mm) PP type is H 67 mm.
For 204: W 118 x D 82 x H 40 (mm) PP type is H 42 mm
For 705: W 118 x D 82 x H 62 (mm) (PP type)
For 503/ 703: W 118 x D 82 x H 64 (mm) PP type is 67 mm
For 801: W 118 x D 82 x H 101 (mm)
For 505: W 118 x D 82 x H 63 (mm)
For 502/ 706/ 804: W 131 x D 89 x H 92 (mm)
For 805: W 131 x D 89 x H 143 (mm)
For 401: W 131 x D 89 x H 143 (mm)

Please refer to the “Microplate Dimensions Chart (PDF)” for various dimensions of culture plates and tighter plates.※The dimensions table provided is only for products listed in the comprehensive catalog.