Elemental Contamination
Issue
The Blank is reporting 100's of thousands of counts for a specific analyte while the other analytes being reported are within a normal range
Environment
- iCAP Q
- iCAP RQ
- iCAP TQ
- ECCN: EAR99
Resolution
The first step is to locate the source of where the potential contamination could be coming to.
1) Disconnect the sample inlet from the nebulizer and block air from entering into the nebulizer by placing a piece of parafilm over the inlet. The Data Display can then be used to gauge as to whether the counts have dropped to a normal range.
a) If the counts come back into a normal range then suspect that the contamination is coming from a source before the nebulizer. This could be any of the sample tubing including peristaltic pump tubing, capillary tubing, and autosampler probes.
Another viable path for contamination is the reagents being used in the diluent, i.e. Deionized water and acids. Try finding another source of Deionized water, if running an aqueous application, to experiment. Another idea would be to utilize the Tune B or Setup solution if the elements which is reading high is not contained within this solution.
b) If the counts don't come back into normal range proceed to step 2
2) Remove the spray chamber elbow from the injector tube holder and see if the counts have dropped to a normal level. Below is a picture of what this setup looks like.
a) If the counts remain high in this configuration, suspect deposition on the cones and clean the cones. This would especially apply to low mass elements. Also it is a good idea to visually inspect the injector tube to ensure that it is free of buildup.
b) If the counts drop to normal levels then suspect a dirty spray chamber and proceed to clean it. To do this take the spray chamber and if running an aqueous matrix soak in a cold bath of concentrated acid for a couple of hours. This can be 50% HNO3 / 50% Deionized H2O if only using NItric acid in your matrix or 25% HNO3 / 25% HCL / 50% Deionized H2O if using a matrix consisting of both Nitric and Hydrochloric acid.