CELLine Flask

Conventionally, cell culture methods were quite laborious and often times produced less than ideal results in terms of low cell density. In addition, these methods require significant purification. That’s why Wheaton has pushed the boundaries once again and invented Celline flasks that address these areas of limitation in static tissue culture flasks.

Our main goal was to facilitate and innovate how science implemented the study of cell culture. Our new line of membrane driven flasks will produce a high-density cell culture that will allow the scientist a more abundant sample.

Wheaton continues to push the envelope in terms of providing the highest quality scientific instruments allowing science to trust their equipment and use it to their fullest potential.

Evolving with Science

Since the late 1800s, Wheaton has served the scientific community by providing top of the line science tools. We have managed to grow in relation to the advances made in science. From research to development and manufacturing, Wheaton applies the philosophy of continual innovation. We believe that only through a perpetual analysis of our own processes can we best cater to the needs of modern science.

Wheaton has long been praise for the discovery of new scientific instruments and continue to invest in the discovery of future tools.

Since the 1940’s, Wheaton has placed significant interest in developing tools for biosciences and virology. In order to assist in the development of life saving vaccines, we commissioned our engineers to create the necessary tools to facilitate new discoveries within this field.

Thus, we have created an innovative new Celline Flask that produces a higher density cell culture.

Problems with Conventional Cell Cultivation Devices

Conventional methods of small-scale bio-production required a lot of effort from the scientist and often times didn’t deliver optimal results. Handling, transporting and storage are all issues related to the conventional methodology.

Many times due to the nature of these conventional devices, scientists were forced to replicate several samples in order to have a large enough culture to work from. This would cost not only time but also valuable resources from the laboratory.

It was evident that Wheaton had to step in and innovate these tools in order to speed up the process of cell culture and reduce the overhead costs of all operations.

Benefits of Celline flasks

Wheaton’s Celline flasks reduces the handling requirements through the implementation of metabolite regulating upper membranes which allows for longer run times as well. It’s like a drip feed mechanism that will regulate the nutrient access for the cells. This allows for bulk media storage during your operation.

With the Celline flasks, you obtain maximum gas exchange as the design places the gas permeable lower membrane directly next to the cells itself. As a result, the oxygen and carbon dioxide transfer reaches optimal levels aiding in cell metabolization.

When it comes to the purification process these Celline flasks create an optimized space for cell proliferation. The upper and lower membrane creates a secluded chamber where there is a reduction of growth factors and hormones and a higher concentration of the antibody and proteins in question.

What makes the Celline Flask so amazing is that it is disposable and ready to implement at will. It creates a much higher cell density with a much more concentrated product. In turn, the operational time it takes to conduct these types of procedures are significantly reduced.

In addition, the need for using a lot of consumables also greatly diminishes.

Compared to conventional methods, these Celline Flasks are much more cost efficient and also less bulky allowing you to stack them on top of each other in order to save space. Most probably, the best feature of the Celline flask is that you do not require any other equipment to use it. Everything comes equipped with exactly what you need and if you are finished with the study, you can discard it.

Many scientists and labs have found that our line of Celline Flasks have saved them thousands of dollars and many hours of hard work. With our product, you find that not only will your work be conducted with ease; all the tedious hassles have been taken care of for you.

How does a Celline Flask function?

Our Celline flasks are composed of numerous parts. The entire assembly consists of a media port, a harvest port, pipette tip stop, harvest tube, metabolite regulating upper membrane, cell compartment spacer, gas permeable lower membrane and the base.

This assembly provides optimum conditions for your cell culture to thrive.

The media compartment allows you to store a great amount of cell culture growth medium. In turn, this significantly reduces the requirements to refresh the media as our design is fifty times the size of the cell compartment. We engineered it in this manner in order to provide longer growth periods and lower chance of cross contamination to occur.

The Metabolite Regulating Upper Membrane regulates the flow of metabolites in between the cell compartments. With a 10kDa cut off limit, the nutrient flow is highly regulated and consistent inspiring greater cell growth.

Within the Cell compartment, we have created the perfect area to inoculate and obtain the highest density cultures. The function of this compartment is to concentrate the cell, their products and it also limits the possibility for any external factors to contaminate the sample. We believe that by creating this compartment we increase the overall efficiency and purity of the sample.

At the bottom above the base, we have implemented a gas permeable lower membrane, which is placed directly against the cells. This allows for the absolute best in obtaining optimal levels of oxygen and carbon dioxide allowing for a more intense culture development.

As you can see, the process is quite simply but very effective. The device comes with absolutely everything you need to grow your next cell culture. We know that you, along with thousands of scientists who have already experienced the wonders of our Celline Flasks, will find that this is a must have in your lab.

What are the basic processes involved with Celline Flasks?

The Wheaton Celline Flask follows very simple processes in order to make cell culture development easier. Following is a brief overview of the six steps it takes to start harvesting your cell culture:

Step 1: The first step is to warm the nutrient medium and to prepare the upper membrane. You achieve this by adding a small amount of media to the top compartment, better known as the “Media Compartment”

Step 2: The second step is to inoculate the cell compartment of the device. The cell compartment is located at the rear end of the Celline flask. Simply remove the cap and apply.

Step 3: Once this has been achieved, you will fill the media compartment. There are indications as to how much needs to be filled. This compartment is fifty times larger than the cell compartment, which prolongs the medium exchange process.

Step 4: Once you have your media compartment filled to your desire it’s time to incubate in CO2. Depending on the optimum harvest schedule, you will leave the container in the incubator for roughly thee or seven days.

Step 5: If you have achieved desired results you can begin to harvest the cells from the cell compartment. However, if you require refilling the media compartment, we recommend between three, five and seven day feeding schedules however you can also customize your schedule to suit your specific cell culture.

Step 6: In the case that you had to refill the media, simply replace the Celline flasks back into the incubator and repeat until you have obtained the desired result.

A Wide Variety of Options

Wheaton provides a wide range of devices to grow a number of cell cultures. We have created these different compartment sizes in order to give the scientist options within the lab. Our sizes range from 350 mL to 1000 mL and we also provide a customizable option where you can request your own specifications where we would manufacture on demand.

Wheaton facilities pride itself by providing the best options for scientists to complete their life’s work!

A More Humane Approach

Many scientists have found that Celline Flasks provide a more humane alternative to using in vivo methods and work just as well. Obviously, there are certain instances when these methods need to be used however; these Celline flasks have proven to be just as effective in most cases.

Our Celline flasks are used for a number of applications such as antibody production, viral cultures, exosome production, protein production and much more. No longer do you need to use mice to obtain your cultures, you can use a Celline Flask as a viable substitution.

Celline Flask Applications

Our Celline bioreactors are suitable for a range of different culture application and due to its innovative design will cultivate cells at a higher density and higher concentrations. Our products do not require any adaptation to your cell culture technique as it is designed to be suitable for serum-supplemented or serum free cultures. We specifically created this to give the scientist freedom within the exploration of cell culture.

Our Celline flasks are perfect for laboratory scale applications using adherent cells attached to microcarriers. With this device, you will be able to cultivate hybridomas and many other cell types including SF, NSO and more.

Our Celline adherent is adapted to facilitate the growth of anchorage dependent cells such as CHO, BHK and HEK cells. Our bioreactor has a polyethylene terephthalate matrix woven together within the cell compartment. This creates a perfect environment for cell attachment to the surface of the membrane.

With our innovative approach to this technology, we implemented a two-compartment cell line. This means that any nutrient deficiency or oxygenation problems have now been taken care of. We have created our devices to be roughly two magnitudes higher than conventional static cell culture techniques.

In addition, due to the high densities of the cell cultures, the concentration levels of the product that can be reached with the Celline flasks are between 1 to 5mg per mL. This means that our bioreactor is perfect for antibody expression in Hybridomas, protein expression in transfected cell lines or even virus production. We have found that with this technology you can find product concentrations at roughly 50-100 times above what can be done with conventional static cell culture techniques.

Our Celline flasks are designed in such a way that maintaining your culture over a long period of time is quite simple. Due to the fact that we have created separate compartments, you can now easily and continually feed your cells without the fear of causing any mechanical stress to the culture. This means that you have the ability to continuously harvest sample specific cells as well as study the nature of your cell culture over time. Our device will sustain your culture for weeks and even months depending on the cell culture you are working with.

How to obtain optimal results with your Celline Flask

We have gone through the trouble of providing you with a “best practices” section, which you can rely on to help you achieve optimal, results with your Celline flasks. We described the basics of this process however here we’ll jump into more specific practices that will facilitate your grow.

Media Preparation

One of the most crucial aspects is handling the medium prior to use. Start by heading the medium to 37 degrees Celsius prior to adding it into the Celline flask. The large medium volume requires heating in order to prevent the cells from experiencing reduced temperatures for a long time. It maintains the heat quite effectively.

Media Composition

Wheaton always tries to provide the greatest amount of flexibility within our products. Thereby there is no need to adapt the media composition for growing cells in our devices. However, with the innovation of two compartments, we provide the scientist greater flexibility over traditional cell culture flasks.

Since our devices produce such a high-density cell culture, we recommend that you use a high glucose medium with a minimal concentration of 2.5 g/l.

With our semi-permeable membrane, we have created a separation from the cell compartment and medium compartment in terms of medium composition. When it comes to serum use in nutrient medium the standard protocol goes as follows. The cell compartment is supplemented with about 15% serum whereas the nutrient medium will only contain 1% FCS serum and in almost all cases, they are entirely free of FCS serum.

When you are using serum free medium formulations, we recommend keeping both compartments serum free. Our customers have found that instead of using expensive serum free medium, they rather used standard medium without serum in the cell compartment, and only 10% in the nutrient compartment. This not only saved them money but time as well.

Finding Media Equilibration

In order to avoid breaking when adding liquid we recommend that you wet the semi-permeable membrane before inoculation. This will ensure that your membrane remains compliant throughout the process.

Inoculating your Culture

In order to obtain speedier results the more cells you have inoculated, the quicker the capacity of the Celline flask will be reached. A typical Celline flask 1000 will allow you over 400 x 106 viable cells whereas the Celline350 can allow up to 135 x 106 viable cells. All of your cells will be limited to the cell compartment.

When you need to Harvest your Cells

Our three to seven day harvesting cycle is meant to more of a reference point as opposed to a requirement. The time in the incubator relies heavily on the type of cells you are using and you need to look at the viability and individual growth characteristics within the Celline flask. As a general rule of thumb, the best-secreted protein production can be acquired when the culture viability is hovering around the 50% marker at the time of harvest.

You could also opt in for harvesting every three days and replace the medium every six days. This is merely another protocol to follow and have proven to be successful for quick result studies. Always make sure however that the culture viability is roughly at 50% when harvesting.

Depending on your own approach to harvesting, the Celline flask provides flexible options for you in the lab. You could even harvest every three days and then inoculate half of the cells. This can go in combination with completely replacing the medium at the time of each harvest.

Depending on your growth characteristics, the results can vary. Our job at Wheaton was to create options for scientists and to allow them to explore with whichever creative process they choose. Your Celline flask will be an asset to diversifying your results and harvesting schedules.

A Few Cell Harvesting Techniques Explained

The Celline flask semi-permeable membrane is very thin. At roughly 8 microns thick, this membrane is delicate however strong enough to withstand normal handling. Dropping, banging or shaking the flask can break the thin membrane and thus it is important to empty the medium compartment with caution. Use fluid motions and allow gravity to clear the medium.

When working with our Celline Adherent flasks, try not to attempt careless maneuvering when you are harvesting your cells. If not done properly, the PET inlay matrix can become detached. In addition, by setting the vacuum of the pipette aid to a low value may minimize the amount of cells that will be removed from the cell compartment. Despite this, the entire process is much simpler than it sounds.

What to do with Osmotic Flux

It is possible for the protein gradient across the semi-permeable membrane to drive water from the medium compartment to the cell compartment. What this means is that you could experience a dilution of growth factors that can affect the growth of your cells. You can compensate for this by adding an excess of serum or growth promotion elements within the cell compartment in order to maintain the desired concentration levels. For instance, if your cell culture method relies on a 10% FBS concentration, we recommend raising it slightly to 15% within the cell compartment.

It is important however to monitor cell compartment volume during harvests in order to cater to the serum needs of your specific culture. If you require obtaining a stable cell compartment volume, you should get rid of the protein gradient on the membrane. You can supplement the medium compartment with inexpensive protein.

How to avoid liquid coming back out of the cell compartment when removing pipettes

It is important to note that when you are manipulating the cell compartment volume, you must loosen the cap. Since this bioreactor works on such a minimal scale, any changes within the compartment volume will create an increase of pressure. This pressure pushes medium out of the media compartment and into the cell compartment. When you simply loosen the cap, you allow that pressure to escape instead of pushing through the membrane. Once you have concluded all your manipulations, simply tighten the cap once more.

How to completely empty your Celline flask

When you pour out the medium from the Celline flask, it is important to keep the flask completely upside down. This creates the ideal pouring angle and will prevent the any left over medium on the lip of the neck when emptying your flask. If there is still a drop left after pouring, you can simply remove it with a pipette. If you decide to use an alcohol pad, remember to only use sterile pads to not cross contaminate or damage the membrane.

How to avoid condensation

We have specified earlier that it is important to pre-warm the medium to 37oC prior to placing it inside the incubator. Since our Celline flasks have such a large medium compartment, condensation can occur. If you are worried about a leak, the solution is very simple. All you have to do is take a dry white paper towel and dab the condensed parts. If there is no color to the water then you know that the excess liquid was due to condensation.

Avoiding Cell Compartment Burst

We have designed our Celline flasks to consider osmotic flux of water into the cell compartment. Thus, we have created a recommended protocol in relation to working volume. For the Celline 350 a recommended 5 mL is suggested and with the Celline 1000 and Celline 1000 Adherent, the recommendation is at 15mL. While the membrane is fragile, if you follow these recommendation you shouldn’t have a problem with cell compartment burst occurring. You can exceed the recommendations in terms of compartment volumes up to 1.3 times without suffering any problems. Nonetheless, we recommend rather playing it safe than pushing the envelope too much and ruining your experiment. Our engineers have worked on foreseeing most of these issues however if you exceed the recommendations we cannot guarantee results.

How much cells are recovered by Celline Flasks

If we are talking about cells growing in suspension, you should be able to retrieve nearly 100% of your cells. With some gentle pipetting you will be able to recover the cells fairly easily and if required you could also provide an additional rinse of clean medium to ensure that you have a complete cell recovery.

In relation to our Celline Adherent flasks where the cells are attached to a PET inlay matrix, gentle pipetting in an upward and downward motion should suffice. However, in most cases we have found that in order to obtain complete recovery of the cells you will need to apply a dissociating agent into the cell compartment.

Knowing how much nutrients to put into your Celline flasks

Wheaton has a variety of Celline flasks with different volumes for nutrients. Our Celline 350 holds 350mL whereas our Celline 1000 holds 1000mL. It is absolutely important that you do not exceed these volumes as the device has been designed to have an air passage to the medium compartment. By exceeding the volumes, you stand risk of membrane failure.

How much can the Semi-Permeable Membrane withstand?

Our upper semi-permeable membrane is very thin however has been designed to withstand common use. Being only 8 microns thick the membrane can experience failure if the flask is banged or shaken if there is liquid within the cell compartment. Under a typical scenario, you can expect the membrane to maintain its integrity for well over a month.

Why you should wet the membrane prior to placing cells in the cell chamber

Prior to inoculation Wheaton recommends wetting the membrane in order to ensure that, the membrane remains compliant. Since the membrane is so thin, a dry membrane is more susceptible to breaking due to volume changes. You cannot remove any air from the cell compartment unless you have pre-wetted the membrane and filled it with liquid. Dry membranes simply cannot handle the stress in volume changes into the cell compartment.

Can the Membrane become clogged over time?

Our devices have never shown a decrease of culture volume over time suggesting that there is no significant clogging that occurs. We have noticed consistent transference of nutrients and a consistent growth within cultures when using our devices.

How to reduce the risk of contamination

We recommend using a vacuum system when removing the medium. If you do not have access to vacuum systems and are pouring out the medium, simply clean the neck of the bottle with a sterile Pasteur pipette. If you are going to use alcohol, be sure to use sterile alcohol pads. Wheaton has created a Celline Class 2 Biosafety Cabinet for handling liquid.

Are there any storage requirements?

Wheaton has gone to great lengths to ensure functionality with design. Our packages come in sterile barrier blister within a foil vapor barrier pouch. Our devices have been stored under ambient conditions with no notable hindrance in performance. Obviously, the device should not be stored in high temperatures in order to avoid any changes within the dimensions of the membrane due to tensile stress. Simply storing it at room temperature should suffice.

What are the number of cells that can be cultured in Celline Flasks?

Our Celline flasks have shown for a typical murine hybridoma a viable cell concentration of around 2-3 x 107 cells/mL. If you supply enough nutrients, you will notice that cell growth will continue within the cell compartment even if you have already reached maximum capacity. In other words, you can obtain significant numbers within one of our Celline flasks. We recommend that when you harvest to maintain 50% viability in order to promote continual development over time.

Can you implement a Serum Free Medium in a Celline Flask?

We have a large number of customers who have obtained phenomenal results when using serum free medium. You must remember to place the serum free medium on both sides of the membrane for most applications. It is important to note that the use of serum free medium may no longer be necessary when our devices are being utilized. Since the secreted protein is retrieved at a high concentration from the flask, you no longer have to concentrate culture supernatant when recovering your antibodies. This takes out any type of interference with serum protein during the purification stage of your cell culture.

What about using high glucose containing medium in Celline Flasks?

For most protocols, the standard RPMI-1640 medium is used. However, some customers who rely on fiber bioreactors have been using richer mediums. As a result, you may observe a slight increase yet is very subjective upon the cell line and should rather be implemented under experimental premises. Nonetheless, by following standard protocols you will obtain stellar results every time.

Is it possible to culture leukemic cells?

With the Celline 1000, we have seen that lymphoblastic cells grow optimally. We have also noticed that cell concentrations of certain lymphoblastic cells have reached nearly twice the amount of concentration as achieved with hybridoma cells. In some cases, you may have to use, serum on both sides of the membrane and should be taken into consideration for personal optimization of condition.

What happens when you cannot focus on your cells?

Some people have found that after initial observations, they cannot refocus on the cells again. What happens in this instance is that when you remove the flask from the incubator, the air temperature drops slightly and in turn contracts the membrane within the cell compartment. This slight contraction will at times take the membrane out of focus. The solution to this problem is very simple. Simply loose the medium compartment cap with equilibrium pressure and return the membrane back to its original position.

Celline flasks versus static culture in terms of antibodies

We have found that the Celline flasks produced the equivalent binding per mg when it was compared to static culture flasks. The advantage of using our devices is that the amount of culture supernatant processing is completely eliminated which frees up time and resources. At the very minimal, you will obtain the same results for less work.

Experiencing Greater Volume than what was inoculated

At times people can find that they harvest greater volumes of cells than what was inoculated. This occurs due to osmotic gradients that traverse the semi-permeable membrane with water. If there is a protein gradient present, as when one uses a no serum medium in the media compartment, the water filters into the cell compartment. This in turn affects colloid protein concentrations due to the fact that small solutes will move across the membrane.

This is why we recommend using 15% serum in the cell compartment when you are implementing a no serum medium in the medium compartment. This will ensure you that serum concentration within the cell compartment to not become diluted to the point where greater volume is experienced.

Wheaton’s Commitment to Continual Innovation

For over a hundred and twenty years, Wheaton has worked side by side with the scientist pushing the envelope in scientific discovery. We have committed ourselves to continually elevating our standards in terms of quality and production, and will keep on investing into research and development.

We know how sensitive your life’s work is and we respect it by pouring quality into our products. The Wheaton line of Celline Flasks is designed to make the life of bio-scientists simpler.

Being the leaders in innovating scientific instruments, we have pledged to maintain our philosophy of merging functionality with design. Before our Celline flasks, cell culture was much more laborious and often times resulted in cross contamination and skewed results.

With Celline Flasks by Wheaton, you know that your cell culture is in the best of hands. Our mission is to keep you focused on what you do best.

We also have committed ourselves to providing the quickest most efficient lab supply delivery service in the world and will send all of your Celline flasks in a sterile environment in order to maintain the integrity of your experiment.

We bring convenience and quality to our clients and always strive to put their needs above all else. A scientist needs a reliable flask that will not fail and will produce high volume and high concentration within their cell culture.

We have perfected the processes of inoculation, nutrient cycles and harvesting by compartmentalization their functions and this has proven to be a great success.

Wheaton continues to push the envelope by designing and innovating new types of Celline flasks and other lab supplies. Don’t trust your cell culture to inferior products, get Wheaton’s Celline Flasks for your lab and speed up your process significantly.