Q: What is the impurity capture column?
Answer: In the process of chromatographic separation, especially when gradient elution or instrument system is used for a long time, it is easy to produce chromatographic peaks that sometimes do not exist, which is commonly known as ghost peak. There are many reasons for ghost peak, but in many cases it is caused by impurities in mobile phase and unclean instrument system.
The ghost Buster column impurity capture column developed by Welch Materials can effectively adsorb and remove impurities in the system, so as to prevent the interference of impurity peak to target peak.
Q: What is the working principle of the small column?
Answer: Many instruments on the market have online filtration devices, which are mainly aimed at the interception of solid particles, but they can not intercept the organic pollutants causing ghost peaks. After careful research and development, Welch Materials has developed a filler that can strongly adsorb weakly polar and non-polar organic impurities without changing the composition of mobile phase (without ion pair reagent), which can effectively eliminate such pollutants, reduce the probability of ghost peaks and prolong the service life of chromatographic column and instrument.
Q: What is the installation and use of impurity capture column?
● When in use, install the impurity capture column between the gradient mixer and the injector. Please ensure that the small column is installed before the injector. If it is installed after the injector, it will have strong adsorption on the sample.
● For the new column, please use 80% methanol water to flush the ghost Buster column impurity capture column with a flow rate of 0.5ml/min, and then connect the equipment for use after 20 minutes.
● Not all impurities can be adsorbed by ghost Buster column impurity capture column.
● If ion pair reagent is used in the mobile phase, it may adsorb ion pair reagent and affect the retention time or peak type of the target. For this kind of mobile phase conditions, please decide whether to use the small column according to the chromatographic effect.
● The service life of impurity capture column is related to chromatographic analysis conditions, mobile phase brand and purity. If the capture effect becomes worse, it is recommended to replace it in time, instead of unlimited use after connection.
● Ghost Buster column impurity capture column is used as a purification widget of the instrument. It is equivalent to the on-line filter on the instrument, but the on-line filter can only filter solid particles, and it can not only filter solid particles, but also purify the organic pollutants in the system, which is a better protection for the instrument and chromatographic column.
● Before and after the use of buffer salt mobile phase, pay attention to the use of high proportion of water for transitional flushing to avoid the precipitation of buffer salt and the blockage of filler.
● When it is found that the capture effect of the small column is not ideal, try to flush the small column with 100% acetonitrile, and the outlet end of the small column shall not be connected to the instrument.
In the gradient system, the impurity trapping column leads to the increase of
Q: What about the effect of mixing lag volume on separation?
Answer: Generally, the impurity collector 4-column is connected with the impurity collector 6-column × The volume of 50mm specification is 400 μ 50. It has little impact on the routine detection. If there is any impact, please connect the impurity capture column to the mixer or switch the water phase channel in front of the valve.
Does it need to be removed to change from gradient to isocratic condition?
It does not need to be removed without affecting the separation effect, because the elution capacity of the mobile phase is the same under equal degree conditions, so ghost peaks are generally not detected, but it does not mean that there are no pollutants in the mobile phase.