ISE8700-8800-8900-Series

Supported Applications

The Omega ISE Standards, ISA & Reference Outer-fill Solutions series provides Ion Selective Electrode (ISE) systems for measuring specific ions in aqueous solutions. The series supports the measurement of Ammonia (NH₃), Ammonium (NH₄⁺), Bromide (Br⁻), Cadmium (Cd²⁺), Calcium (Ca²⁺), Carbon Dioxide (CO₂), Chloride (Cl⁻), Copper (Cu²⁺), Cyanide (CN⁻), Fluoride (F⁻), Fluoroborate (BF₄⁻), Iodide (I⁻), Lead (Pb²⁺), Nitrate (NO₃⁻), Nitrogen Oxide (NOx), Perchlorate (ClO₄⁻), Potassium (K⁺), Silver/Sulfide (Ag⁺/S²⁻), Sodium (Na⁺), Surfactant (X⁺, X⁻), and Water Hardness (Ca²⁺/Mg²⁺). The ISE-8710 Ammonia Gas-Sensing Electrode is used to measure dissolved ammonia in aqueous solutions without requiring sample distillation; the measurement is not affected by sample color or turbidity. It can also be used to measure the ammonia ion after conversion to ammonia or organic nitrogen following Kjeldahl digestion of the sample.

Operating Conditions & Performance

The series operates within process temperature ranges of 0 to 50 °C and 0 to 80 °C, depending on the specific electrode model. Response times are documented as either 30 seconds or 20 seconds across different sensor types. Measurement capabilities span a wide range of concentrations expressed in Molar (M) and parts per million (PPM). For example, Ammonia measurement ranges from 1.0 to 5x10⁻⁷ Molar (17000 to 0.01 PPM), while Copper ranges from 1 x 10⁻¹ to 1 x 10⁻⁸ Molar (6350 to 6.4 x 10⁻⁴ PPM). Slope performance varies by ion, with values such as 57 ±2 mV per Decade for Ammonium and 27 ±2 mV per Decade for Cadmium.

Interferences are specific to the target ion. For instance, volatile amines interfere with Ammonia measurements; K⁺ interferes with Ammonium (PVC); S²⁻, I⁻, CN⁻, and high levels of Cl⁻ and NH₃ affect Bromide; and Ag⁺, Hg²⁺, Cu²⁺ impact Cadmium. The series requires specific reference electrolytes such as NaCl, KNO₃, (NH₄)₂SO₄, or 4M KCL depending on the electrode configuration.

Configuration Options

The ISE8700-8800-8900-Series is available in multiple housing materials and sensor configurations to accommodate different analytical needs. The series supports Epoxy, PVC, and Glass housings. Sensor types include Gas-sensing Combination, Polymer membrane mono, Solid-state mono, and Combination electrodes.

Configuration options for the ISE-8710 Ammonia electrode follow a model number guide structure: ISE-8710 - <Electrode Type> - <Accessory> - <Filling Solution> - <Standard> - <Cap> - <Other Options>. Available accessories and consumables include:

• Standards: 0.1M NH4Cl, 1000 ppm Nitrogen Standard
• Filling Solutions: Ammonia Electrode Filling Solution (PHFS-8710), Sodium Hydroxide Solution (10M)
• Caps and Mounting: Flow-thru cap for flow-thru applications
• Replacement Parts: New membrane (20mm x 20mm) and Small O-ring

The series includes a comprehensive selection of ISE Standards, ISA & Reference Outer-fill Solutions. These are offered in various volumes including Standard solutions (475 mL), ISA (Ion Strength Adjuster) at 475 mL, and Reference Outer-Fill solutions at 125 mL for both Single Junction and Double Junction configurations.

Key Product Differences

The series distinguishes between Epoxy/PVC mono-electrodes and Glass combination electrodes. For example, Ammonium is available as ISE-8711 (PVC housing, Polymer membrane mono) or ISE-8712 (Glass housing, Combination). Similarly, Bromide offers ISE-8720 (Epoxy, Solid-state mono) and ISE-8722 (Glass, Combination).

Reference electrode requirements vary by model. Some electrodes utilize a Double Junction Reference Electrode (PHE-3211), while others use a Single Junction Reference Electrode (PHE-3111). The Ammonia Gas-Sensing Electrode connects to the meter in the same manner as any other combination electrode and does not require an external reference electrode. Specific pH ranges are defined for each ion, such as "above 11" for Ammonia, "4 to 10" for Ammonium (PVC), and "2 to 14" for Bromide.