(Jiangxi New Materials Co., Ltd.)
The glass liner in the capillary vaporization chamber of the chromatograph, during use, due to the special properties of the sample, causes Residues in the silanized glass-lined tube will lead to poor repeatability of retention time and area, detection of ghost peaks, instrument baseline fluctuations, noise interference and other malfunctions.
Usual processing method: first take out the inner liner reasonably and observe the shape of the glass liner, such as the shape When abnormality occurs, correct analysis cannot be performed. Observe whether the inner wall of the glass liner is contaminated or has sample pad debris. Some contaminants are the cause of repeatability errors or ghost peaks. The glass liner is damaged. Damage is caused by The reasons for poor repeatability are quartz wool in the glass liner and improper filling of quartz wool.
Chromatograph lining tube
How to clean glass liner
Remarks: graphite pressure The solvent attached to the ring is the cause of ghost peaks
Please remove the graphite pressure ring when cleaning the glass liner with solvent. Remove the injection pad residue attached to the quartz wool. Use a thin rod to poke out the quartz wool and install new quartz wool. Remove dirt adhering to the inner wall of the glass liner. After removing the quartz wool, scrub the inner wall with gauze soaked in solvent (acetone, etc.). The heavily dirtied part on the inner wall of the glass liner is immersed in a solvent (acetone, etc.) for several hours. Then, wipe the inner wall with gauze dipped in solvent.
DMCS (dimethylchlorosilanization) treatment of glass liners
Phenomenon: The peak reproducibility of some pesticide samples is poor and biased. Adsorption, decomposition, peaks become smaller, and the content is inaccurate. Cause: The glass liner or quartz wool of the inlet is too active. Produce adsorption and decomposition.
Treatment method: 1. Clean the glass liner and quartz wool with acetone and other organic solvents, dry them and soak them in 5% DMCS/n-n-hexane overnight. 2. Take out the glass liner and quartz wool that have been soaked overnight, clean them 2-3 times with methanol immediately, and then soak them in methanol for about an hour. 3. Take it out from methanol, dry it and store it with silane under dry conditions.