© Agilent Technologies, Inc., 2010 April 6, 2010 5990-5631EN Maximizing ICP-MS Productivity for High Matrix Samples Using the 7700x with ISIS Discrete Sampling Integrated Sample Introduction System (ISIS) Achieving the highest productivity in ICP-MS requires optimization of the sample uptake and washout steps, which account for more than half of the overall run time in a typical ICP-MS method. The ISIS option for the 7700 Series can be configured for maximum productivity using Discrete Sampling or DS which, while much faster than conventional sample introduction, still allows multiple replicates to be measured from each sample injection as required by USEPA methods. The Result A standard Agilent 7700x ICP-MS fitted with an optional ISIS-DS system was used for the measurement of a sequence of high matrix standard reference materials, 1/10 diluted seawaters, and all EPA 6020A required QA/QC samples. 275 analyses were performed in 8 hours 8 minutes, with an average run to run time of 1.99 minutes per sample. Excellent internal standard stability (Figure 1) is evidence of superior matrix tolerance and long term stability. Figure 2. The key components of high productivity Combined ICP-MS Technologies for High Matrix Sample Analysis The unique combination of ISIS-DS, HMI and He mode for universal interference removal delivers much faster analysis, while also providing effective removal of polyatomic interferences, and the highest matrix tolerance of any ICP-MS – Figure 2. For more information on the 7700x visit the Agilent Technologies web site at: www.agilent.com/chem/icpms High Productivity Analysis of High Matrix Samples Maximum productivity requires more than just fast analysis times; it also requires the robustness and stability to maintain high speed analysis for an extended period. The typical ICP-MS interface is designed to tolerate samples containing up to 0.2% total dissolved solids (TDS). Above this level, the plasma may become overloaded, leading to: • Signal drift caused by gradual deposition of undissociated material on the interface cones • Higher levels of polyatomic interferences (such as strongly- bound matrix oxides) • Increased suppression (signal loss), especially for poorly ionized analytes such as Be, B, Zn, As, Se, Cd and Hg The Agilent 7700x ICP-MS was designed to alleviate these problems by increasing the matrix tolerance of the plasma, as well as enhancing the performance of the 3 rd generation Octopole Reaction System (ORS 3 ) cell operating in helium collision mode (He mode). Agilent High Matrix Introduction (HMI) System The 7700x includes the unique HMI system which dilutes the aerosol stream from the spray chamber, thereby reducing the aerosol and matrix loading on the plasma. The result is a significant increase in the effective plasma temperature, which effectively eliminates matrix suppression, and also allows samples containing % levels of TDS to be analyzed routinely, without the need for time consuming dilutions of over-range samples. Helium Collision Mode He mode on the ORS 3 cell is widely acknowledged as the most effective and reliable method for removing the unknown and variable polyatomic interferences typically seen in complex natural samples. Since He mode works for any polyatomic interference, it provides significantly shorter run times compared to reaction cell methods, where multiple cell gases are typically required to address all the interferences that occur in complex samples. ISIS-DS He Collision Mode High Matrix Introduction (HMI) System High Speed Sample Uptake and Rinseout Fast, Reliable Removal of all Interferences Ultimate Matrix Tolerance Figure 1. Minimal Internal Standard signal drift for sequence of 275 high matrix environmental samples (not all sample names are shown)

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April 6, 2010

5990-5631EN

Maximizing ICP-MS Productivity forHigh Matrix Samples Using the7700x with ISIS Discrete Sampling

Integrated Sample Introduction System (ISIS)Achieving the highest productivity in ICP-MS requires optimization of the sample uptake and washout steps, which account formore than half of the overall run time in a typical ICP-MS method.The ISIS option for the 7700 Series can be configured for maximumproductivity using Discrete Sampling or DS which, while much fasterthan conventional sample introduction, still allows multiple replicatesto be measured from each sample injection as required by USEPAmethods.

The ResultA standard Agilent 7700x ICP-MS fitted with an optional ISIS-DSsystem was used for the measurement of a sequence of high matrixstandard reference materials, 1/10 diluted seawaters, and all EPA6020A required QA/QC samples. 275 analyses were performed in8 hours 8 minutes, with an average run to run time of 1.99 minutesper sample. Excellent internal standard stability (Figure 1) is evidenceof superior matrix tolerance and long term stability.

Figure 2. The key components of high productivity

Combined ICP-MS Technologies for High Matrix Sample AnalysisThe unique combination of ISIS-DS, HMI and He mode for universal interference removal delivers much faster analysis, whilealso providing effective removal of polyatomic interferences, andthe highest matrix tolerance of any ICP-MS – Figure 2.

For more information on the 7700x visit the Agilent Technologiesweb site at: www.agilent.com/chem/icpms

High Productivity Analysis of High Matrix SamplesMaximum productivity requires more than just fast analysistimes; it also requires the robustness and stability to maintainhigh speed analysis for an extended period. The typical ICP-MSinterface is designed to tolerate samples containing up to 0.2%total dissolved solids (TDS). Above this level, the plasma maybecome overloaded, leading to:

• Signal drift caused by gradual deposition of undissociated material on the interface cones

• Higher levels of polyatomic interferences (such as strongly-bound matrix oxides)

• Increased suppression (signal loss), especially for poorly ionized analytes such as Be, B, Zn, As, Se, Cd and Hg

The Agilent 7700x ICP-MS was designed to alleviate these problems by increasing the matrix tolerance of the plasma, aswell as enhancing the performance of the 3rd generation OctopoleReaction System (ORS3) cell operating in helium collision mode(He mode).

Agilent High Matrix Introduction (HMI) SystemThe 7700x includes the unique HMI system which dilutes theaerosol stream from the spray chamber, thereby reducing theaerosol and matrix loading on the plasma. The result is a significantincrease in the effective plasma temperature, which effectivelyeliminates matrix suppression, and also allows samples containing %levels of TDS to be analyzed routinely, without the need for timeconsuming dilutions of over-range samples.

Helium Collision ModeHe mode on the ORS3 cell is widely acknowledged as the mosteffective and reliable method for removing the unknown andvariable polyatomic interferences typically seen in complex naturalsamples. Since He mode works for any polyatomic interference,it provides significantly shorter run times compared to reactioncell methods, where multiple cell gases are typically required toaddress all the interferences that occur in complex samples.

ISIS-DS

He Collision Mode

High Matrix Introduction(HMI) System

High Speed Sample Uptakeand Rinseout

Fast, Reliable Removalof all Interferences

Ultimate Matrix Tolerance

Figure 1. Minimal Internal Standard signal drift for sequence of 275 high matrix environmental samples (not all sample names are shown)