Collision / reaction cells applications

Further applications of ICP-MS with a collision/reaction cell in trace, ultratrace analysis and isotope ratio measurements are described in Chapter 8.16 17 20 22 27 28... 

Alternatively, the use of a modified spray chamber in line between the tubing and the plasma connection to increase the signal duration and improve the signal stability has been reported in another archaeometric application [108]. The use of this approach permits the simultaneous aspiration of a nebulized aerosol or of a gas (e.g., N2), which represents another possibility for damping the signal before the plasma. This procedure has been demonstrated to be preferable over the use of a gas inside a collision/reaction cell, as it is able to buffer the effect of the matrix on the mass discrimination [101]. 

Yip Y-C, Sham W-C. Applications of collision/reaction cell technology in isotope dilution mass spectrometry. Trends Anal Chem. 2007 26 727-43. 

There is no question that collision/reaction cells have given a new lease on life to quadrupole mass analyzers used in ICP-MS. They have enhanced its performance and flexibility, and most definitely opened up the technique to more demanding applications that were previously beyond its capabilities. However, it must be emphasized that when assessing this technology, it is critical that you fully understand the... 

F. Keenan and W. Spence, Theory and Applications of Collision/Reaction Cells How Collision and Reaction Cells Work for Interference Removal in ICP-MS, Thermo Fisher Scientific Web-based Presentation, 2007, http //breeze.thermo.com/crcs. 

In fact, these application limitations have led some vendors to reject the cool plasma approach in favor of collision/reaction cell technology. So, it could be that the cool plasma capability of an instrument may not be that important if the equivalent... 

This procedure is applicable to the determination of thirteen elements (Al, As, Cd, Cr, Cu, Pb, Mn, Ni, Se, Ag, Tl, V, and Zn) in acid digested FGDW, utilizing a collision/reaction cell to remove molecular interferences and internal standardization to compensate for suppression and enhancement effects caused by sample matrices. Let us take a closer look at this procedure. 

In fact, these application limitations have led some vendors to reject the cool plasma approach in favor of collision/reaction cell technology. So, it could be that the cool plasma capability of an instrument may not be that important if the equivalent elements are superior using the collision/reaction cell option. However, you should proceed with caution in this area, because on the current evidence not aU collision/ reaction cell instruments offer the same kind of performance. For some instruments, cool plasma DLs are superior to the same group of elements determined in the collision cell mode. For that reason, an assessment of the suitability of using cool plasma conditions or collision/reaction cell technology for a particular application problan has to be made based on the vendor s recommendations. 

For this reason, it should also be emphasized that when you are comparing systems, it should be done with your particular analytical problem in mind. In other words, evaluate the interference suppression capabilities of the different collision and reaction cell interface approaches by measuring BEC and DL performance for the suite of elements and sample matrices you are interested in. In other words, make sure it works for your application problem. This is even more important with the newer triple quadrupole collision/reaction cell approach because it is complicated and at the time of writing, there are very few applications in the public domain. 

Because of the disparity of the reaction rates of the two neutralization reactions, the analyte can be efficiently determined after the introduction of ammonia as a reactive gas into the multipole. There are many excellent reviews about the development and applications of collision/reaction cell in ICP-MS. " In order to eliminate the new isobaric interferences produced by secondary reactions, two methods are commonly used in the commercial instrument the discrimination of kinetic energy or mass filtering. " The former mainly utilizes the post-cell kinetic energy discrimination (KED) to suppress transport of the produces of the side reactions to the analyte in the hexapole and octapole cell instruments. Whereas in the latter, the quadrupole cell has a capability to reduce the formation of the unwanted side product ions by selecting an appropriate mass bandpass. The details of the KED and bandpass approaches can refer to many excellent books and reviews. " " ... 

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