HPLC - Frequently Asked Questions

General HPLC Column Questions	Column-Specific Technical Questions	General Technical Questions
General Business Questions

General HPLC Column Questions

Question: What is the difference between ODS-2 and ODS-3?

Answer: ODS-3 is part of the "3 Series" of GL Sciences Inertsil product line. The 3-Series product line was an improvement on the 2-series product line, in that the silica purity was increased, the chemical and physical stability of the silica was enhanced, and the bonding and end capping were optimized to create a more deactivated phase. Additionally, ODS-3 provides much lower operating pressure than ODS-2. We will always supply ODS-2 and the rest of the 2-Series (C8, Ph, C4, Sil 150A) for established methods. But for new methods, we recommend trying the 3-Series products.

Question: How long should my column last?

Answer: Ah, the age-old question that every chromatographer struggles with. If your sample is perfectly free of particulates, does not bind not specifically to the column packing, and is completely innocuous towards the silica and bonded phase chemically, your colulmn can last for thousands of injections. However, this ideal situation exists only in most HPLC column manufacturing QA/QC labs. In the real world, your column may last between 1 and 5000 injections, depending on your sample, sample preparation, and how the colulmn is treated and stored.

Question: When I first connected my column, the pressure was fine and I achieved good peak separation. Now the pressure has increased and my peaks are not as sharp and my retention times are inconsistent. Why?

Answer: Most likely, your sample or sample matrix contains components that are sticking to the injector, the column frit, or the column packing material. This is common with many real-world HPLC samples. You will need to devise a sample preparation method, including filtration, along with a column cleaning and storage regime that helps promote maximum column lifetime.

General Business Questions

Question: What is the difference between Inertsil I have gotten from other vendors and Inertsil I receive directly from GL Sciences, Inc?

Answer: GL Sciences, Inc. invented Inertsil and has made the silica packing material, in it's Japan manufacturing factory, for EVERY Inertsil column ever sold. In the past, some vendors obtained bulk materials and packed their own columns. To avoid inconsistencies in product performance, testing, labeling, etc., GL Sciences, Inc. discontinued selling bulk packing in 2005. Now, all Inertsil columns you use, regardless of the source, should have been produced by GL Sciences in Japan.

Question: Does GL Sciences sell directly to customers?

Answer: Yes, we sell directly to end-users as well as company-specific purchasing organizations such as VWR and Fisher.

Question: How do we set up an account?

Answer: Simply, call, FAX, or email a purchase order containing Ship-To, Bill-To, Attn:, Purchasing Agent Contact phone and email, Accounts Payable Contact phone and email, end-user email, items to be ordered including order numbers and descriptions if available, a EIN for Corporations or SS for Sole Proprietors, and a purchase order. We'll confirm the order with you almost immediately whichever way you choose to start business with us. GL Sciences' EIN number is 20-2340664 and we are a California C Corporation.

Question: Does GL Sciences provide eCommerce?

Not at this time. We will be initiating eCommerce during the late spring of 2007 for our 50 most popular items.