pH Measurement for Low Volume Flow

The Sensorex pH Detector is designed for use with a variety of instrumental techniques such as FIA, HPLC and IEF.  It also is used to continuously monitor the pH of low volume flows in bench scale chemical systems.

The 50 and 200 microliter internal volume flow cells are available in acrylic or PVDF. (Consult factory for details of other construction materials.) They are supplied with inlet and outlet fittings sized for standard 1/16" OD tubing. The cells' ports have 1/4-28 threads which accept a variety of other tube fittings.

The small internal volumes of these pH Detectors are achieved by using a flat surface pH electrode located at the top of the flow cavity. The resulting rectangular cross-section flow path has no protruding parts which could interfere with a clean, sweeping flow.

The result of this design is the fast system response shown on the performance curves in the data sheet. Download the PDF (to the right) for complete details.

The Flat Surface Electrode, Sensorex Model S450C, is a combination pH/Reference electrode.  It includes both a pH and reference half cell.   The reference electrode is a sealed, gel-filled design and includes a peripheral, semi-porous polyethylene junction. For applications where unwanted chemical reactions can occur in the presence of silver or chloride ions, a double junction version is available, Model S450CD.  Use the double junction  where proteins precipitate in the presence of heavy metals such as silver. The double junction design will prevent this precipitation. Both single and double junction versions of this combination electrode are supplied with a 76 cm (30 inch) cable and with a variety of connectors. 

Flow Cells

The following flow cells are provided with 1/16 inch tube fittings.  Order the pH Electrode separately.

pH Electrode

These electrodes are supplied with 76 cm (30 inches) cable. Please specify needed connector or make and model of pH meter you will be using.