The SRS^® 300 Self-Regenerating Suppressor^® uses AutoSuppression^® technology. The ions required for eluent suppression are generated by the continuous electrolysis of recycled water, truly state of the art.

A New Era in Suppression

The SRS 300 uses AutoSuppression, a technique that goes beyond the power of classical chemical suppression, to combine high performance with unparalleled ease-of-use. The SRS 300 offers:

• Low background noise levels
• Fast startup and equilibration times
• Trace anion and cation determinations
• Ability to interface to a mass spectrometer
• Compatibility with all Dionex ICS and DX chromatography modules
• Three-fold increase in backpressure tolerance compared to previous generations

The SRS 300 Self-Regenerating Suppressor enhances analyte conductivity while suppressing eluent conductivity (background). This results in a dramatic improvement in analyte detection limits. The ions required for eluent suppression are generated by the continuous electrolysis of water, therefore, there are no regenerant solutions to make and no need for off-line regeneration of the suppressor.

The SRS 300 delivers low backgrounds and low noise levels for the full range of Dionex ion-exchange IonPac columns and eluents, even under high concentration gradient conditions. Combined with the revolutionary Eluent Generator, it delivers truly automated, minimal-maintenance Reagent Free ^TM  Ion Chromatography (RFIC ^TM ).

Low Background Noise Levels

The ability of an ion chromatograph (IC) to reach method detection limits (MDLs) at ppb and sub-ppb concentrations is dependent upon many system parameters affecting sensitivity. Because sensitivity is determined the ratio of signal to noise, one of the most important system parameters is the ability of the suppressor to suppress the eluent and lower background conductivity. The suppressor must also lower the baseline noise so the data system can differentiate the signal from noise for integration. If the suppressor is "noisy" (because it does not suppress adequately or has unacceptable electronic noise)  ppb sensitivity cannot be achieved. The SRS 300 will help you improve your MDLs by offering low background and baseline noise, along with the capacity required to suppress even high-concentration gradient eluents.

Ruggedness

New hardware enhancements have improved the ruggedness of the SRS 300 by improving its backpressure tolerance threefold over previous suppressors.

Fast Start-Up Equilibration Times

These improvements provide improved noise performance and faster startup time upon the initial installation, and day-to-day startup. This means you can start running ppb-level analyses within 2 hours of initial installation or after about 10 minutes with day-to-day startup.

ASRS^® 300 for Trace Anion Determinations

The major benchmark application of sensitivity in IC is the ability to analyze trace-level anions in drinking water. Perchlorate, also, can be determined down to 0.5 ug/L using the AS16 and ASRS 300 suppressor.

For anion applications the SRS 300 is the premier hydroxide suppressor and provides low noise performance under a variety of concentrations. For example, the suppressor is designed to support the high-concentration (65 mM KOH) requirement of the perchlorate application with AS16 chemistry.

Atlas^® Suppressor for Carbonate-Based Applications

The ASRS 300 also provides lower noise and improved startup time for carbonate applications, however the suppressor noise performance will not be as good as the standard Atlas suppressor.

CSRS^® 300 for Cation Applications

For cation applications, the CSRS 300 handles all applications covered by the standard CSRS ULTRA II and CSRS ULTRA suppressors and gives comparable or better results.

Interface for IC/MS

In addition, new revisions to EPA Method 314.0 will mandate the confirmation of perchlorate by the molecular ion at 99 m/z and the isotopic molecular ion at 101 m/z. 

The mass spectrum below clearly demonstrates that no interferences are present from the ion chromatograph, the column, or the suppressor at these mass ranges.

Previously a special version of the standard ASRS ULTRA II (2-mm) suppressor that had been preconditioned for fast startup and minimal sulfate interference was required for IC-MS applications. With the SRS 300, the entire family of suppressors receives this preconditioning so no special version is required for IC-MS applications. The ASRS 300 (2-mm) is the recommended solution for anion systems employing MS detection.

Upgrade to the SRS 300

The good news is that if you own a Dionex IC,  you can take advantage of the capabilities of the SRS 300.  The new SRS 300 products directly replace the SRS ULTRA II. All you need to do is install the new SRS 300 into your current system.

Two versions will continue to be available: the ASRS 300 for anion analysis and CSRS 300 for cation analysis. Both versions offer rugged design, solvent and gradient compatibility, and can be operated at temperatures up to 35 °C for anion versions or 40 °C for cation versions. The suppressors are available in 2- and 4-mm formats.

The SRS Gas-Assisted Regeneration Kit provides low noise without the need for external water, significantly reducing water usage and waste. The gas-assisted recycle mode is a method of SRS operation that replaces the external water mode for aqueous eluents. For eluents containing solvent, the gas-assisted external water mode can be used to reduce the amount of deionized water required for regeneration.

Displacement chemical regeneration (DCR) mode is an easy-to-use mode of operation for chemical suppressors. DCR mode eliminates the need for pressurized regenerant bottles or a regenerant pump. In this mode, the regenerant is displaced with conductivity cell effluent, delivering the regenerant to the suppressor at a flow rate equal to the eluent flow rate. At setup, the regenerant bottle is completely filled with regenerant. As the cell effluent is pumped into the regenerant bottle, the regenerant is forced out into the suppressor regen chambers. No additional pump or pressure is required. Eluent and regenerant bottles are of equivalent volumes and new regenerant is prepared when new eluent is installed. The low regenerant flow rate, which is equivalent to the eluent flow rate, minimizes waste and allows unattended operation, offering an economical option to the AutoRegen^® or pressurized bottle modes.

The Suppressor Cleanup Kit provides off-line cleanup of suppressors. The kit includes one 1-L plastic bottle, one pressure regulator (0–30 psi/210 kPa), one 2-way valve, and all of the tubing and fittings required for operation.