Author Archive

Tailing solvent peak during split injection? Check your column installation distance!

When performing splitless injections, it is not uncommon to witness a tailing solvent peak, given the large amount of solvent introduced onto the column over a relatively long period of time.  For split injections, however, only a small portion of the solvent loads onto the column and it occurs very quickly. This results in a […]

Are My Shut-off Valves Contaminated?

Shut-off valves provide a convenient means to control gas flows and are often used in conjunction with gas chromatography systems.  There are several types of shut-off valves including ball valves, plug valves, and diaphragm-sealed valves.  Some of these valves, ball and plug valves included, use a silicone-based lubricant to make opening and closing the valve […]

Check out Dual Vespel® Ring Inlet Seals

Inlet seals are a critical component for ensuring a leak free seal at the base of a GC inlet.  For those of you who are using standard inlet seals on Agilent or Thermo Trace instruments, Restek also offers an alternative known as the Dual Vespel® Ring seal.  This seal features a Vespel® ring on each side […]

The “Breakdown” of Endrin and DDT for Non-Environmental Chemists

As the title makes clear, this post is aimed more at non-environmental laboratory personnel who are not familiar with US EPA methods.  If you are one of those environmental lab gurus who shudders at the sound of a “pesticide degradation check”, this is probably stuff you already know. Anyways, for the rest of you, you […]

LVI-SV with MMI Inlet Using a Restek Premium 2.0 mm Single Taper Liner w/ Wool

Agilent’s Multimode (MMI) Inlet can be used as a PTV (programmable temperature vaporization) type inlet for large volume injections, with the advantage of using standard sized split/splitless liners.  This technique requires careful optimization of a number of parameters, which starts by choosing a proper inlet liner.  I recommend trying a Restek Premium 2.0 mm Single […]

Improve Recoveries and Precision for Splitless Injections by Using Wool

The use of wool in liners for splitless injections provides many advantages, including enhanced vaporization, protection of the column by acting as a trap for non-volatiles, and sample mixing/homogenization. Recently, I was asked the question, “For splitless injections, how much of a difference does wool make as far as enhancing vaporization?”  There is no simple […]