An innovative spin on proven technology
The SDX HPLD system combines the proven ASX-560 autosampler with a novel vortex mixing dilution accessory. The SDX makes use of a high precision syringe pump for both aliquot and diluent, but goes an additional step to vortex mix the resulting dilution prior to sample introduction to ICP and ICP-MS.
The SDX employs vortex mixing to promote homogenization of a sample to ensure accurate and precise analysis following dilution. The variety of sample matrices submitted for trace element analysis necessitates the need for mixing. This capability is long overdue, and should only improve data quality by fully homogenizing a dilution mixture rather than in-line combination.
SDX HPLD Technology Description
During normal operation the autosampler probe draws a sample which passes through the SDX module and continues to the ICP.
For a dilution, the same probe is connected to a high resolution syringe pump for aliquot and diluent addition to the vortex mixing vessel. Following measurement, any remaining sample is drained and the vortex vessel is cleaned.
Dilution and Mixing
- The probe line is primed with diluent
- The syringe pulls the prescribed amount of diluent
- The probe pulls up an air gap
- The probe moves into the sample and takes the prescribed aliquot
- The probe moves to the vortex vessel and dispenses both aliquot and diluent and the mixture is vortex mixed
- The probe switches to normal operation then samples the homogenous solution
The SDX HPLD system can be set to rinse the vortex mixing vessel as many times as desired to ensure there is no carryover. The sample flow path and vortex mixing vessel are comprised completely of inert materials that are free of trace metals and easy to clean.
Vortex Mixing and Cleaning
- Aliquot and diluent are delivered to the vessel
- Vessel is mixed
- Dilution is sampled
- Fresh rinse is added and mixed
- Waste is pumped away
The SDX HPLD uses an independent rinse source from the ASX-560 Autosampler so that, if needed, a different rinse solution can be used for the autosampler probe versus the SDX-HPLD vortex mixing vessel.
The Teledyne CETAC SDX HPLD system redefines “intelligent dilution” with the ability to re-analyze a sample in a single step to fall within range. On the recognition that an analyzed sample falls outside of the calibration range the sample is re-diluted at a new dilution factor that has been calculated by the system so that it falls within the calibration range and will provide a signal of the order of 60% of that of the top calibration standard. Thus, reanalysis is only performed once and not through an incremental dilution process.