Bubbles Forming When Using Inlet Filters for HPLC Mobile Phases.

Bubbles Can Form in an HPLC Mobile Phase. When an HPLC pump is active, a vacuum is present in the tubing and any Filter that is connected to the pump. If the liquid cannot flow fast enough, an Air Bubble will result which is commonly called “cavitation”. This cavitation can occur for a variety of […]

Read More

Can I Use Acetone as a Mobile Phase Solvent in ANP? – FAQ

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 […]

Read More

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 […]

Read More

Can I use SS tubing with my MicroSolv sparging stone?

Our sparging/filter stones are designed to work with low pressure tubing such as PTFE, FEP, ETFE, or PFA. We offer two types of sparging devices. One type is will require the tubing to be inserted and screwed into the sparging stones. Inside there are small, sharp chads or barbs that grips into the soft tubing holding it in place. If tubing […]

Read More

How Much Volume can the 47mm HPLC Membrane Filters Handle?

The 47mm Membrane Filters can be used for vacuum Filtration of Solvents. In most cases, one of these Filters can be used until it is blocked with Particulate Matter at which time, the flow through the membrane will cease. In most applications you will use the Filters for removing small amounts of Particulate Matter from […]

Read More

How Often do You Need to Change Filters for the Filter/Degasser?

The frequency at which the Filter Membrane has to be replaced is dependent on the sample’s volume of undissolved particles. The more particles, the more frequently it has to be replaced and vice versa. For relatively clean samples (e.g. mobile phases) you could change the membrane every 500 mL or so. Filter/Degasser Product Page

Read More

How to Avoid Microbial Growth in HPLC Mobile Phases.

Bacteria can be a problem in the case of Aqueous Solvents. If present, they can create problems for an instrument’s operation. There are a few things you can do to avoid their formation in your mobile phase. One is to add an acid such as 0.1% Formic Acid. Many HPLC methods may use an acidified […]

Read More

Should I filter my HPLC Solvents and Buffers before use? – FAQ

The most common cause of excessive back pressure is due to the accumulation of particulates and or permanently adsorbed materials at the top of the HPLC Column. This could be precipitate or un-dissolved particles which can come from your samples or your mobile phase or shredded pieces of pump seals. The best way to minimize […]

Read More

Should I use methanol as the organic solvent for ANP in HPLC?

Methanol is generally not recommended for most ANP applications however a few scientists have seen success with it. Instead, it is best to use polar aprotic solvents such as acetonitrile. If using ELSD or LCMS, acetone can also be a good alternative to acetonitrile as well. However, because of its high UV cutoff, it is generally […]

Read More

The pH range of common buffers for HPLC.

The following table shows a list of common buffers and their working buffer ranges: Buffer pH Range  trifluoroacetic acid (TFA)  1.5-2.5  phosphoric acid/monobasic phosphate (pKa 1)  1.1-3.1  formic acid/formate  2.8-4.8  acetic acid/acetate  3.8-5.8  mono/dibasic phosphate (pKa 2)  6.2-8.2  ammonia  8.2-10.2  1-methylpiperidine  9.1-11.1  triethylamine  10.0-12.0 As for concentration, about 5mM is suitable for Cogent TYPE-C Silica™ […]

Read More

What are the dimensions and specifications of the 10L reservoir bottles?

Our 10L (10,000ml) solvent reservoir or mobile phase storage bottles have the following specifications: Material:                   Borosilicate Glass Code 7740 Safety Coating:        Proprietary epoxy plastic Capacity:                  10000 mL Bottle Style:              Storage Neck Style:               Wide Mouth Top Style:                 Threaded Cap Style:                 Plug Seal Cap Material:            Polypropylene Bottle Shape:           Cylindrical Cap Color:                Orange Thread Finish:          45 GL Graduation Range:  2000-9000 […]

Read More

What is an “inlet sinker” in HPLC?

I am not exactly sure, but “inlet sinker” has been used as another name for stainless steel sparging stones or stainless steel inlet filters. This term may be used since the stones are heavy and sink to the bottom of the mobile phase inlet bottles. Click HERE for HPLC Mobile Phase Filtering Ordering Information Including Sparging Stones

Read More

What is the pressure limit of the stainless steel sparging stones?

All the sparging stone products are rated to 1000 bar. However it is important to note that the tubing used and the connection of the tubing to the device may not perform at this pressure rating. The pressure limit of sparging stone is not for the filters/spargers, but for the connections. Mobile Phase Filters Ordering Information

Read More

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 […]

Read More