If you are using LCMS, the simple answer is yes but pH is also something to consider. Acetone has a high UV cutoff and therefore can be a problem for UV detection. However, this is not a problem when using LCMS or ELS detectors such as the Corona CAD. You can use Acetone to replace Acetonitrile […]
Category: Mobile Phase Suggestions
Can I use benzene as a mobile phase solvent in HPLC?
Benzene can be used as an HPLC solvent in theory. It is compatible with standard HPLC instrumentation and will not damage an HPLC column. However, we would not recommend using this solvent for two main reasons. First, it is strongly UV-absorbing so would not be suitable for UV-based detection methods. Second, it is a known carcinogen and therefore […]
Can you use a Sparging Stone for Removal of Dissolved Oxygen? FAQ
Yes, Sparging Stones have been shown to remove dissolved Oxygen (or CO2) from Water or Wine. The efficiency of Sparging is influenced by many factors, such as Bubble Size, Contact Time between the Gas and Wine, Temperature of the Wine, Gas Pressure, and the Flow Rate of Gas in relation to the Flow Rate of […]
Compatibility Guidelines for Safety-Coated Mobile Phase Reservoir Bottle Use – Tips
The plastic coating of the Safety-Coated Mobile Phase Reservoir Bottle is not compatible with dry heat in excess of 110 °C, an open flame or other direct heat source, use on hot plates, autoclaving above 121 °C, or temperatures below -20 °C. However, it is compatible with use in dishwashers or microwaves, provided that the […]
Do the MicroSolv mobile phase bottle caps have holes to insert tubing through?
Yes, there are three holes in the top of the cap which are threaded for use with standard low pressure male nuts as shown below in the image. This cap has 2 different size through holes which allows for two different size tubing or different venting while the other size (shown) has one size threaded hole […]
How to prepare 10 mM ammonium acetate buffer, 90:10 in acetonitrile for HPLC and LCMS. – Tips.
When you see something like “10 mM ammonium acetate in 90:10 acetonitrile : buffer” in a method, you may be wondering how exactly this mobile phase solution is prepared. For example, is it 10 mM with respect to the total solution (i.e. with acetonitrile added) or just with the aqueous component? Do you just mix […]
How to Use Bubble Point to Filter Water through Hydrophobic Membranes.
Bubble Point pressure is the differential pressure required for a liquid to flow through a dry filter membrane. The differential pressure is either a positive pressure on the liquid layer on top of the membrane or a vacuum applied below the membrane or a combination of the two. The bubble point pressure is determined by […]
Ideas on Pressure Increases after Each HPLC Injection – Tip
Question: I am injecting cell extract samples on my HPLC instrument and I find that the back pressure increases after each run. Any ideas on what the problem might be? Answer: There are a number of possible causes. First, always be sure to sonicate and filter your mobile phase before introducing to the LC system especially […]
If I do not degas my mobile phase for HPLC, what are the consequences? – FAQ
Solvents that are exposed to the atmosphere have the ability to absorb compressible CO2 and Oxygen. When your HPLC has low back pressure, the actual linear flow of materials could be different then when you have higher back pressure. This is due to the compressibility of air v. the compressibility of gas. This means that […]
Use Teflon bottles for A and B solvents in negative ion mode LCMS.
You will want to have both your A and B solvents (aqueous and organic) in Teflon mobile phase reservoir bottles. The reason for using these bottles is that sodium present in borosilicate glass mobile phase reservoirs can lead to issues for anionic analytes in negative ion mode LCMS. These include phosphates and organic acids but […]
Why is Nylon called Nylon? FAQ
According to the “Answers Corporation” website, nylon was developed at both New York and London, simultaneously. However, it has also been stated that the letters “nyl” were arbitrary and the “on” was copied from the suffixes of other fibers such as cotton and Rayon. A later publication by DuPont (Context, vol. 7, no. 2, 1978) […]
Why should I use your Bottle Caps for HPLC Mobile Phase Bottles – FAQ
Keep your mobile phase content consistent and clean while preventing dangerous pressure build up in the bottles. Keeping these caps on the bottles with the tubing through it prevents dust and dirt from getting in to the solvents and reduces outgassing from the same solvents and reduces absorption of CO2 from the atmosphere to keep […]