Restek is a leading developer and manufacturer of chromatography columns and accessories. We provide analysts around the world with the innovative tools they need to monitor the quality of air, water, soil, foods, pharmaceuticals, chemical, and petroleum products.
Nice video! this is in my school materials, i could see what bleeding is on a graph but couldn't put it in the right words. Now i know that it is additional unwanted signals in the graph caused by the degradation of the stationary phase caused by a reactive chemical like a strong acid or base or by oxygen contamination so it is very important to filter for oxygen in the carrier gas.
This can vary greatly. As a default, we'd always recommend checking with your instrument manufacturer's guidelines. These are generally around every six months. How much you are injecting, how much is your split, how dirty are your samples can all impact this. Cleaning split vent lines is generally reserved for a situation where you feel it is needed, such as seeing some ghost peaks or other evidence of contamination. In an extreme case, when you notice incorrect flow rates and may suspect some clogging.
Sou de São Paulo Brasil e trabalho com um cromatógrafo com duas colunas e quando injeto a mesma amostra nos dois, tem muita diferença no resultado, e sinal do fid do front e 6,2 e do back está em 7,8. vou fazer um vídeo e mostrar aqui nos comentários ok.
Muito obrigado amigo, moro em São Paulo Brasil, e trabalho com um cromatógrafo com duas colunas e uma está com o sinal (fid) muito alto, o front está com 6,2 e o back com 7,8, quando injeto a mesmo amostra nos dois, dá uma diferença, e também no final da corrida e sinal aumenta muito. Vou fazer um vídeo mostrando o ocorrido.
Can you help me, the back detector shows temp not installed. And my infront gas (N2) flow rate i set is 45, but the screen show range 51 - 60. Can you help?
I have faced an ignition cut-off when the sample was injected. Upto injection of sample flame is on and shows a good signal. but when injected immediately, the ignition will cut. what is the reason? can you please tell me?
What are you injecting and how much? You may wish to troubleshoot by trying to inject less or a different solvent. You can also do an no injection instrument blank to see if it is a timing/flow issue rather than the injection itself. You can find instructions on how to do that here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-tpebPhvQERY.htmlsi=DNIgtobWEzHsxpe3
I have an Agilent ZORBAX NH2 and Carbohydrate column which is used for HILIC separation for sugar. Since those 2 columns have not been used for a period of time. Which solvents are suitable to use for cleaning and regeneration?
For any specific column, we would always recommend referencing the original manufacturer's instructions. Here is some information that may be helpful www.agilent.com/cs/library/datasheets/public/820629-008D.pdf For general information on LC column regeneration, we have a nice blog post www.restek.com/chromablography/resurrecting-an-old-reverse-phase-lc-column--should-i-could-i-how-would-i
In the past, the serrated edge was recommended for use for cutting some smaller ID metal columns. Generally, even those are now recommended to be cut with the smooth edge.
Can one extrapolate two neighbor peaks with resolution below 1.0? Is it correct to integrate the area of extrapolated peaks that are artificially deconvoluted?
Compounds like carboxylic acids, can be very difficult to get good peak shapes. Depending on the column phase, there may be columns specifically designed to work with acids that can help. Stabilwax-DA columns are an example. Derivitization is also used for some compounds to improve peak shapes - fatty acids are often methylated before being analyzed for this reason. Some analysts also do priming injections - injecting high concentration standards to help occupy active sites before doing their analytical injections. There are many options, but they can all have their pros and cons.
Congratulations for the video, but I don't understand how a pulsed split injection can have the liner with increased pressure if the injector outlet opens?
The pressure controls of the GC system are designed to handle these pressure changes. So while there is still flow going through the column (and out the split vent, septum purge, etc.) pulsed injection allows users to temporarily elevate the pressure in the injection port.
Hi sir, In case of benzene in carbomer as per USP method ... the benzene standard getting deterioration after 1 or 2 injections through splitless mode where i have been connected with split line in the GC...is this problem are having connection with split liner...
That will depend on your instrument. Many can use standard compression fitting caps, but you should check your instrument manual or instrument manufacturer to be sure.
I'm careful if I can ask here, but is it possible to analyze isophthalic acid by GC-MS? I have been having a tailing problem for a month. I will buy all the products you recommend. Somebody help me T^T
Tailing happens when the analyte of interest retains in the column. How the oven is programmed, gas flow rate, or the column used could impact your acid. You might need to look into different columns since you are dealing with aromatic acids, like Chromaton N-AW-HMDS with 5% Apiezon L column.
