The MicroSolv Zero and Controlled Flow CE capillaries are definitely compatible with the standard Beckman PA800 and MDQ capillary cartridges. These capillaries have a 360um OD and should have no issue with the standard cartridges. NOTE: These capillaries are not precut to size nor do they have a detection window. This would be the responsibility of the user to […]
Category: Zero Flow Capillary FAQ
At what temperature do I store the neutral-coated Zero Flow Capillaries?
The capillaries should be stored at room temperature (approximately 22C) in a dry place. It does not depend on the ID of the capillary. Many customers actually tape them to the wall near their CE instrument. Capillaries for CE Ordering Information
At which pH will my CE method optimize with these capillaries?
These capillaries columns are pH independent. What that means is the flow does not change significantly with different pH levels. The optimal pH will be the pH at which your analytes separate best. Click here to view Zero and Controlled flow capillaries for CE
Can I use a laser to make a window for the Controlled Flow/Zero Flow Capillaries?
No, these capillaries have a special covalently bonded coating on the inside capillary wall (linear polyacrylamide) that may be damaged using a laser. The outer polyimide coating should be removed only by a specific protocol. This procedure uses fuming sulfuric acid to chemically remove the outer polyimide coating. Capillaries for CE Ordering Information
Can I use the MicroSolv Window Maker or similar units on the Zero or Controlled Flow CE Capillaries?
It is not normally recommended that one use high heat to remove the polyimide coating on the capillary. This could create a “void” in the wall coating and produce erroneous results. It is best to use chemicals to remove the polyimide in this case. Be sure to follow good laboratory practices when using hazardous chemicals. […]
Do you sell bared fused capillaries for CZE that are completely UV-transparent?
No, all of our CE capillaries are coated with polyimide. This polymer imparts structural rigidity to the capillary but has the disadvantage of being non-UV-transparent. Without the coating, the capillary would be very brittle and will break easily. However, this does not present a problem in typical usage since you only need a small portion of the […]
Do you sell CE capillaries of various outer diameters?
The only outer diameter (OD) bare fused silica capillary for CE that we sell is 365µm. Capillaries for CE Ordering Information
Do you sell CE capillaries with pre-made windows?
We do not sell CE capillaries with a pre-made window for a few reasons; most importantly, the window is fragile often causing damage during shipping. In order to ensure quality capillaries are delivered to our customers, it is best that the end-user makes the window themselves. Another reason we do not offer these capillaries with pre-made windows is […]
For the bonded or coated CE capillaries, do you have other lengths?
The bonded or coated capillaries are only available in 1M lengths. The reason is that it is very difficult to push the bonded reagent through a 50um or 75um tube and get proper coating. Ordering Information for Controlled Flow and Zero EOF Capillaries
How can I remove polyimide from your capillaries without using heat?
To remove polyimide coating from our Simplus™ brand or Zero™ or Controlled Flow™ capillaries for CE without using heat, it is best to use fuming sulfuric acid at 100°C. You may want to heat the acid on a hot plate in a small shallow plate, using a fume hood and all the safety equipment needed. Then dip the capillary into […]
How do the CE capillaries provide different amounts of flow?
We coat the bare fused silica with a proprietary polymer that has a large amount of Sulfonic acid groups exposed to the lumen of the capillary. The different flow rates of the columns are due to differing amounts of polymer. The more the polymer the less of a flow. Click here to view Zero and […]
How does the Zero Flow CE Capillary work?
The Zero Flow™ CE capillary is made from a bare fused silica capillary but has an inner coating which is covalently bonded with linear polyacrylamide (LPA). Since it does not have any ionizable groups it is considered “effectively neutral” and has not charge. Therefore noticeable EOF is not observed when using this capillary even when current is applied across the field […]
I don’t see buffer coming out of the Zero Flow™ Capillary. Is the capillary defective?
Zero Flow™ Capillaries by MicroSolv are designed to be Electro-Osmotic-Flow (EOF)-free. This is due to a covalently bonded inner coating that eliminates surface hydroxyl group activity responsible for bulk flow or EOF. Therefore it is normal to observe “no eluent” of buffer or any liquid even at high voltages. This can be beneficial because uncontrolled EOF is known to contribute to a lack […]
If I use a buffer at pH of 9.0 and temperature of 30-35C with the Zero EOF Capillaries (cat# 04650-ZF), what capillary lifetime should I expect?
If you use a pH buffer even with moderate ionic strength, at pH 9, the capillaries would not be expected to last very long. It is hard to predict how many runs you get because it will depend on your run times, your conditioning step, etc. However, these capillaries are not designed for a pH higher than 8. The silica […]
Is the conditioning of the Controlled and Zero CE capillaries the same as with a bare fused silica capillary?
No. Inside the front cover of the column case is a special set of conditioning steps that must be taken. It is important that these conditions be followed. You can also see these conditions on our website by clicking on this link: Controlled Flow capillary Conditioning Steps. Click here to view Zero and Controlled flow capillaries […]
What are the terms such as high flow rate in Controlled Flow CE capillaries based on?
The terms High, Medium and Low are based on a relative flow when compared to Bare Fused Silica Capillaries. The Controlled Flow capillary always is slower than bare silica but the High Rate is the highest of the Controlled Flow capillaries. A set of conditions on a bare silica column that provides a migration time […]
What is a Zero EOF CE capillary mostly used for?
There are many uses for Zero EOF in HPCE. One use is to allow analytes to separate based on electrophoretic mobility only. The Zero EOF capillary is an excellent choice for this technique because, regardless of the pH you use to ionize your analytes, the flow will still be zero. Another use is cIEF. Click […]
What is the proper way to remove the outside polyimide coating on Zero EOF Capillaries without damaging the inner polymer coating?
Normally one would use high heat from the CE Window Maker™ or a similar item to remove the polyimide coating of a CE capillary. However, the polymer that is present on the inside wall of the Zero EOF Capillary will be damaged so it is not recommended. The void that results at this section of capillary will adversely affect […]
Which internal diameters (ID) do these CE capillaries come in?
These capillaries are available in both 50m and 75m ID width. The length of the capillary is 1 meter. Click here to view Zero and Controlled flow capillaries for CE
Will my analyte absorb to the polymer used in the Controlled or Zero Flow coated capillaries for CE?
The Controlled and Zero EOF Capillaries usually produces a very low sample to polymer interaction (wall) and absorption. Your analytes could be different however as it will depend on the hydrophobicity of your analyte. The more hydrophobic and neutral, the more chance it will be adsorbed. If it is charged it is not likely to stick. […]