You have successfully installed your TOC analyzer and, as suggested, you run a “Leak Check” prior to starting your analysis. The leak check fails, so you tighten everything, perform another leak check, and still, the instrument does not pass. Without a plan of attack, this can be frustrating and time consuming. Fortunately, there are some troubleshooting techniques that can help.
Tags: TOC, Total Organic Carbon, Teledyne Tekmar, Analyzer, Combustion
Troubleshooting analytical instrumentation can be a cumbersome process. If we remember a few rules, the task can be simplified. First, take a moment to review the manuals for the instrumentation. Second, examine the facts and use valid reasoning to identify the root cause of the problem. Concentrate on anything that may have changed, like a column, trap, etc. Avoid “quick fixes” as they may cause more problems down the road. The most important thing is to be patient.
Tags: Purge and Trap Concentrator, GC/MS, chromatography, Analytical Instrumentation, Concentrator, Autosampler, GC, MS
With helium increasing in scarcity and price, many laboratories are looking for cheaper and more readily available alternatives. Some have also been restricted or cut off completely from their suppliers due to the demand. In the realm of gas chromatography, this leaves hydrogen and nitrogen as the most viable alternatives for carrier gas. Gas generators are available from a variety of vendors for both hydrogen and nitrogen. Installation of one of these generators can lead to considerable cost savings over its lifetime, especially when changing from helium gas cylinders. New methods are also starting to allow alternative gases to accommodate these supply challenges.
Tags: hydrogen, nitrogen, helium, gas alternative
In gas phase analysis, water can be a big challenge. Like the analytes of interest, it is volatile. Generally in gas chromatography, water can be the enemy of just about every component of the GC, from the injector to the column to the detector. And when using a purge and trap concentrator for the sample preparation, the matrix is water, so dealing with it is unavoidable. Our task, then, is to try to decrease the amount of water and minimize the effects of water on the GC and the resulting chromatography.
Tags: Purge and Trap Concentrator, chromatography, US EPA Method 524.3, SIM, US EPA Method 524.2, gas phase analysis
The Unregulated Contaminant Monitoring Program (UCMR3) recently announced a new rule that requires public drinking water facilities to collect data on roughly 30 contaminants from January 2013 through December 2015. For the VOC portion of this rule, seven (down from the original nine) were selected for analysis by US EPA Method 524.3, using selective ion monitoring (SIM) to reach MRLs as low as 0.03 µg/L.
Tags: VOC, drinking water, US EPA Method 524.3, Unregulated Contaminant Monitoring Program, UCMR3, selective ion monitoring, SIM