pH and Electrochemistry
Instruments and other methods to measure pH, conductivity, specific ions, dissolved oxygen, and other parameters; may be handheld or benchtop and manual or electronic (analog or digital); includes pH indicator papers, electrodes, and other probes.
pH and electrochemistry meters and related products are used to assess acidity and alkalinity, conductivity, specific ion concentrations, and dissolved oxygen in water, wastewater, and other solutions. Electrochemistry meters may measure a single parameter (like pH) or they may be multiparameter meters, capable of performing a combination of tests (pH plus conductivity, for example).
Electrochemistry meters are used with various probes and electrodes designed for specific purposes or types of solutions. Electrodes with epoxy bodies are useful for testing food, beverages, and other materials where broken glass could be a problem. Other electrodes are made to withstand higher than usual impact; for use with solutions that contain large particulates; and for compatibility with biological buffers.
Electrodes must be carefully stored and maintained for optimal performance. It’s important to select the right storage bottles and electrode filling, cleaning, rinsing, and storage accessories.
Electrochemistry meters also require regular calibration and maintenance. Standard and certified pH buffers as well as conductivity and specific ion standards are available. Other accessories include electrode supports, bulb guards, cables, connectors, and adapters.
Indicator paper and test strips are another simple, portable, and qualitative way to quickly determine pH and other analytes. The paper or strips contain chemical indicators that produce color reactions. A comparison chart (included) helps to interpret the results. Available in various pH ranges, these are sometimes called “litmus” paper.
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Thermo Scientific™ Orion™ ROSS Ultra™ Epoxy Bodied pH/ATC Triode™
Accurately measure pH and temperature together in just one electrode, with a built-in temperature sensor.
| Type | pH/ATC Combination Electrode |
|---|---|
| Warranty | 18 Months |
| Length (Metric) | 120 mm |
| Precision | 0.01 |
| Isopotential Point | 7 |
| pH Range | 0 to 14 |
| Diameter (Metric) | 12 mm |
| Filling Solution Type | None required |
| Material | Rugged Epoxy Body, Filled with Low Maintenance Gel |
| Junction | Glass Capillary |
| pH Relative Accuracy | 0.03 pH for buffers using automatic temperature compensation |
| Temperature (Metric) Operating | 0°C to 80°C |
| Internal Reference | ROSS |
Thermo Scientific™ Orion Star™ A322 Conductivity Portable Meter PROMO
Accurately monitor conductivity, TDS, salinity, resistivity and temperature with this conductivity portable meter designed for challenging field tests.
Thermo Scientific™ Orion™ Ionplus™ Sure-Flow™ Bromide Combination Ion Selective Electrode
Measure bromide ions in aqueous solutions quickly, simply, accurately and economically.
| For Use With (Equipment) | ISE Meter |
|---|---|
| Junction | Sure-Flow Junction |
Thermo Scientific™ Orion™ Star A325 pH, Conductivity and Temperature Portable Waterproof Multiparameter Meter Kit - PROMO
Retrieve accurate results from any location with the Thermo ScientificTM Orion StarTM A325 pH/Conductivity Portable Multiparameter Meter.
Thermo Scientific™ Orion™ Versa Star Pro™ DO Benchtop Meter
Get premium performance and flexibility with this benchtop meter with module for dissolved oxygen (optical/polarographic) and temperature.
| Power Rating | DC input: 9VDC, 1A |
|---|---|
| Temperature (Metric) Range | -5.0°C to +105.0°C |
| Resolution (Polarographic DO) | 0.01, 0.1mg/L |
| Pressure Range | 400 to 850mmHg |
| Memory | Non-volatile memory preserves data log, calibration log and meter settings |
| Languages | English, Spanish, French, Italian, German, Chinese, Portuguese and Korean |
| Measurement Modes | Dissolved Oxygen (% Saturation),Dissolved Oxygen (mg/L with Temperature and Barometric Pressure) |
| Power Supply | Universal AC adapter (included) |
| Barometric Pressure Correction | 400 to 850mmHg, automatic using built-in barometer or manual entry |
| Data Management Details | Transfer single, range or all data points to printer or computer |
| Display Type | Color graphic LCD with user-customizable options |
| Data Points | 2000 with Date and Time Stamp |
| Calibration Modes | Water-saturated air, air-saturated water, manual (Winkler titration), zero point |
| Certifications/Compliance | CE, TUV 3-1, FCC Class A |
| Temperature Probe Calibration | 1 point temperature offset calibration |
| Salinity Factor | 0.0 to 45.0 ppt, automatic correction using manual entry of sample salinity |
| Stability | Selectable fast, medium, slow or Smart Stability setting; Selectable off or Automatic Smart averaging setting |
| Warranty | 3 year meter and module warranty |
| Sensor Types | RDO optical dissolved oxygen sensor or polarographic dissolved oxygen sensor |
| Percent Saturation Range Polarographic DO | 0.0 to 600.0 % saturation |
| Log Function Type | Automatic data logging with Auto-Read, Timed and Single Shot measure modes; manual data logging with |
| Relative Humidity Range | 5 to 85 %, non-condensing |
| Range (RDO) | 0.00 to 50.00 mg/L |
| Dimensions (L x W x H) | 28 cm x 24 cm x 10 cm (11 in. x 9.5 in. x 3.9 in.), modules add ≤ 2 cm (0.8 in.) L & H |
| Percent Saturation Range (RDO) | 0.0 to 500.0 % saturation |
| Temperature Selection | Automatic with ATC temperature probe |
| Keypad | Numeric with menu-specific function keys and dual purpose scroll/shortcut keys |
| Outputs | USB (2), RS232 |
| Backlight Option | Yes |
| Percent Saturation Relative Accuracy (RDO) | ±2 % saturation ≤ 200 % saturation, ±10 % saturation > 200 % saturation |
| Range (Polarographic DO) | 0.00 to 90.00 mg/L |
| Accuracy (Barometer) | ±6mmHg |
| Methods | 10 per channel |
| Pressure Resolution | 0.1mmHg |
| Channels | 4 (Customizable with modules) |
| Resolution (RDO) | 0.01, 0.1mg/L |
| Percent Saturation Resolution (RDO) | 0.1, 1 % saturation |
| Percent Saturation Relative Accuracy (Polarographic DO) | ±2 % saturation or ±2% of reading whichever is greater |
| Inputs | 9 pin MiniDIN (RDO optical or polarographic DO sensor with built-in temperature), two stirrer inputs (stirrer probe) |
| Accuracy (Temperature) | ±0.1°C |
| Weight (Metric) | 1.2 kg, modules add 0.2 kg each |
| Temperature (English) Operating | 41°F to 113°F (ambient) |
| Accuracy (Polarographic DO) | ±0.2mg/L or ±2% of reading, whichever is greater |
| AC Adapter | Universal 50-60 Hz, 100-240 VAC power adapter (Cat. No. STARA-PWR) |
| Alarm Output | Set point alarm, high/low limit alarm, calibration due alarm |
| IP Rating | IP-54 |
| Percent Saturation Resolution (Polarographic DO) | 0.1, 1 % saturation |
| Weight (English) | 2.5 lb., modules add 0.5 lb. each |
| Resolution (Temperature) | 0.1°C (0.1°F) |
| Temperature (Metric) Operating | 5°C to 45°C (ambient) |
| Percent Saturation Range (Polarographic DO) | 0.0 to 600.0 % saturation |
| Accuracy (RDO) | ±0.1mg/L up to 8mg/L, ±0.2mg/L from 8 to 20mg/L, ±10% of reading up to 50mg/L |
Thermo Scientific™ Orion Star™ A323 Dissolved Oxygen Portable Meter
Accurately monitor dissolved oxygen (optical/polarographic) and temperature with this RDO/DO portable meter for challenging field testing.
| Temperature (Metric) Range | 0.0°C to 50.0°C |
|---|---|
| Resolution (Polarographic DO) | 0.01, 0.1mg/L |
| Pressure Range | 400 to 850mmHg |
| Memory | Non-volatile memory preserves data log, calibration log and meter settings |
| Languages | English, Spanish, French, Italian, German and Chinese; Portuguese and Korean available with software update |
| Measurement Modes | Dissolved Oxygen (% Saturation),Dissolved Oxygen (mg/L with Temperature and Barometric Pressure) |
| Power Supply | 4 AA batteries (included) or universal AC adapter (sold separately) |
| Barometric Pressure Correction | 400 to 850mmHg, automatic using built-in barometer or manual entry |
| Battery Life | 800 hours |
| Data Management Details | Transfer single, range or all data points to printer or computer |
| Display Type | Graphic LCD with Backlight |
| Data Points | 5000 with Date and Time Stamp |
| Calibration Modes | Water-saturated air, air-saturated water, manual (Winkler titration), zero point |
| Certifications/Compliance | CE, TUV 3-1, FCC Class A |
| Temperature Probe Calibration | 1 point temperature offset calibration |
| Salinity Factor | 0.0 to 45.0 ppt, automatic correction using manual entry of sample salinity |
| Stability | Selectable fast, medium, slow or Smart Stability setting; Selectable off or Automatic Smart averaging setting |
| Warranty | 3 Year Meter Warranty |
| Sensor Types | RDO optical dissolved oxygen sensor or polarographic dissolved oxygen sensor |
| Percent Saturation Range Polarographic DO | 0.0 to 600.0 % saturation |
| Log Function Type | Automatic data logging with Auto-Read and Timed measure modes; manual data logging with Continuous m |
| Battery Type | Four AA (included) |
| Relative Humidity Range | 5 to 85 %, non-condensing |
| Range (RDO) | 0.00 to 50.00 mg/L |
| Dimensions (L x W x H) | 24 cm x 10 cm x 6.5 cm (9.5 in. x 3.9 in. x 2.6 in.) |
| Percent Saturation Range (RDO) | 0.0 to 500.0 % saturation |
| Temperature Selection | Automatic with ATC temperature probe |
| Keypad | Comprehensive with menu-specific function keys and dual purpose scroll/shortcut keys |
| Outputs | USB, RS232 |
| Backlight Option | Yes (Selectable) |
| Percent Saturation Relative Accuracy (RDO) | ±2 % saturation ≤ 200 % saturation, ±10 % saturation > 200 % saturation |
| Range (Polarographic DO) | 0.00 to 90.00 mg/L |
| Accuracy (Barometer) | ±6mmHg |
| Methods | 10 per channel with password protection |
| Pressure Resolution | 1mmHg |
| Channels | 1 |
| Resolution (RDO) | 0.01, 0.1mg/L |
| Percent Saturation Resolution (RDO) | 0.1, 1 % saturation |
| Percent Saturation Relative Accuracy (Polarographic DO) | ±2 % saturation or ±2% of reading whichever is greater |
| Inputs | 9 pin MiniDIN (RDO optical or polarographic DO sensor with built-in temperature) |
| Accuracy (Temperature) | ±0.1°C |
| Weight (Metric) | 0.5 kg |
| Temperature (English) Operating | 41°F to 113°F (ambient) |
| Accuracy (Polarographic DO) | ±0.2mg/L or ±2% of reading, whichever is greater |
| AC Adapter | Universal 50-60 Hz, 100-240 VAC power adapter (sold separately, Cat. No. 1010003) |
| Alarm Output | High/low limit alarm, calibration due alarm |
| IP Rating | IP-67 |
| Percent Saturation Resolution (Polarographic DO) | 0.1, 1 % saturation |
| Model | Orion Star A323 RDO Optical/Dissolved Oxygen/Temperature Portable Meter |
| Weight (English) | 1.2 lb. |
| Resolution (Temperature) | 0.1°C (0.1°F) |
| Temperature (Metric) Operating | 5°C to 45°C (ambient) |
| Percent Saturation Range (Polarographic DO) | 0.0 to 600.0 % saturation |
| Accuracy (RDO) | ±0.1mg/L up to 8mg/L, ±0.2mg/L from 8 to 20mg/L, ±10% of reading up to 50mg/L |
Thermo Scientific™ Orion™ Cupric Ion Selective Electrodes
Measure cupric ions in aqueous solutions quickly, simply, accurately and economically.
| Type | Combination ISE |
|---|---|
| For Use With (Equipment) | ISE Meter |
| Junction | Sure-Flow Junction |
Thermo Scientific™ Orion™ Iodide Ion Selective Electrodes
Get fast, stable and reliable iodide ions readings in aqueous solutions.
| For Use With (Equipment) | ISE Meter |
|---|
Thermo Scientific™ Orion™ Versa Star Pro™ Conductivity Benchtop Meter
Get high accuracy, premium performance and ultimate flexibility with this conductivity benchtop meter designed for conductivity, total dissolved solids (TDS), salinity, resistivity and temperature.
| Power Rating | DC input: 9VDC, 1A |
|---|---|
| Salinity Measurement Modes | Practical salinity (psu) or natural sea water (ppt) |
| Range (Resistivity) | 2 ohm to 100.0 megohm |
| Memory | Non-volatile memory preserves data log, calibration log and meter settings |
| Languages | English, Spanish, French, Italian, German, Chinese, Portuguese and Korean |
| Measurement Modes | Conductivity,TDS,Salinity,Resistivity with Temperature |
| Power Supply | Universal AC adapter (included) |
| Data Management Details | Transfer single, range or all data points to printer or computer |
| Display Type | Color Graphic LCD with User-customizable Options |
| Data Points | 2000 with Date and Time Stamp |
| Certifications/Compliance | CE, TUV 3-1, FCC Class A |
| Temperature Probe Calibration | 1 point temperature offset calibration |
| Stability | Selectable fast, medium, slow or Smart Stability setting; Selectable off or Automatic Smart averaging setting |
| Resolution (Conductivity) | 0.001 μS minimum, auto ranging up to 4 significant digits |
| Range (Conductivity) | 0.001 μS/cm to 3000 mS/cm |
| Log Function Type | Automatic data logging with Auto-Read, Timed and Single Shot measure modes; manual data logging with |
| Relative Humidity Range | 5 to 85%, non-condensing |
| Dimensions (L x W x H) | 28 x 24 x 10 cm (11 x 9.5 x 3.9 in.), modules add ≤ 2 cm (0.8 in.) L & H |
| Accuracy (TDS) | 0.5% of reading ±1 digit |
| Temperature Selection | Manual or automatic with ATC temperature probe |
| Keypad | Numeric with menu-specific function keys and dual purpose scroll/shortcut keys |
| Outputs | USB (2), RS232 |
| Backlight Option | Yes |
| Compatible Probes | 2-cell or 4-cell conductivity sensors with built-in temperature |
| Methods | 10 per channel |
| Cell Constant | 0.001 to 199.9 cm-1 |
| Temperature (Metric) Reference | 5, 10, 15, 20, 25°C |
| Channels | 4 (Customizable with modules) |
| TDS Factor Range | Linear (0.02 to 9.99) |
| Range (Salinity) | 0.06 to 80.00 psu, 0.05 to 42.00 ppt |
| Temperature Compensation | Linear, nLFn (non-linear ultra pure water), nLFu (non-linear ultra pure degassed water), EP (off wit |
| Accuracy (Salinity) | 0.5% of reading ±1 digit |
| Resolution (Salinity) | 0.01 psu or 0.01 ppt minimum, auto ranging |
| Accuracy (Conductivity) | 0.5% of reading ±1 digit > 3 μS; 0.5% of reading ±0.01 μS ≤ 3 μS |
| Inputs | 8 pin MiniDIN (conductivity sensor with built-in temperature), two stirrer inputs (stirrer probe) |
| Accuracy (Temperature) | ±0.1°C |
| Weight (Metric) | 1.2 kg, modules add 0.2 kg each |
| Calibration Points (Conductivity) | 6 |
| Temperature (English) Operating | 41°F to 113°F (ambient) |
| Resolution (Resistivity) | 1 ohm or 0.1 megohm, auto ranging |
| Accuracy (Resistivity) | 0.5% of reading ±1 digit |
| AC Adapter | Universal 50-60 Hz, 100-240 VAC power adapter (Cat. No. STARA-PWR) |
| Resolution (TDS) | 0.001 ppm minimum, auto ranging up to 4 significant digits |
| Calibration | Conductivity with calibration editing option and temperature |
| Alarm Output | Set point alarm, high/low limit alarm, calibration due alarm |
| IP Rating | IP54 |
| Weight (English) | 2.5 lb., modules add 0.5 lb. each |
| Resolution (Temperature) | 0.1°C (0.1°F) |
| Temperature (Metric) Operating | 5°C to 45°C (ambient) |
| Temperature Range (Metric) | -5°C to +105°C |
Thermo Scientific™ Orion Star™ A329 pH/ISE/Conductivity/Dissolved Oxygen Portable Multiparameter Meter
Accurately measure pH, ion concentration, conductivity, dissolved oxygen and temperature with our pH/ISE/conductivity/RDO/DO portable meter.
| Salinity Measurement Modes | Practical salinity (psu) or natural sea water (ppt) |
|---|---|
| Resolution (Polarographic DO) | 0.01, 0.1mg/L |
| Pressure Range | 400 to 850mmHg |
| Range (Resistivity) | 2 ohm to 100.0 meg-ohm |
| Memory | Non-volatile memory preserves data log, calibration log and meter settings |
| Advanced ISE Functions | Segmented (point-to-point) slope, non-linear selectable auto-blank, low concentration range stabilit |
| Languages | English, Spanish, French, Italian, German and Chinese; Portuguese and Korean available with software update |
| Measurement Modes | pH,mV,Relative mV,TDS,ORP with Temperature,Salinity,Conductivity,Resistivity with Temperature |
| Resolution (ISE) | 0.0001 minimum, 1 to 3 significant digits (user selectable) |
| Power Supply | 4 AA batteries (included) or universal AC adapter (sold separately) |
| Barometric Pressure Correction | 400 to 850mmHg, automatic using built-in barometer or manual entry |
| Data Management Details | Transfer single, range or all data points to printer or computer |
| Battery Life | 800 hr. |
| Display Type | LCD Graphic, Backlit |
| Resolution (mV) | 0.1mV |
| Data Points | 5000 with Date and Time Stamp |
| Calibration Modes | Water-saturated air, air-saturated water, manual (Winkler titration), zero point |
| Temperature Probe Calibration | 1 point temperature offset calibration |
| Certifications/Compliance | CE, TUV 3-1, FCC Class A |
| Salinity Factor | 0.0 to 45.0 ppt, automatic correction using conductivity reading or manual entry of sample salinity |
| Accuracy (mV) | ±0.2 mV or ±0.05% of reading whichever is greater |
| Accuracy (ISE) | ±0.2 mV or ±0.05% of reading whichever is greater |
| Warranty | 3 Year Meter |
| Temperature Accuracy | ±0.1°C |
| Stability | Selectable fast, medium, slow or Smart Stability setting; Selectable off or Automatic Smart averaging setting |
| Calibration Points (ISE) | 1 to 5 |
| Resolution (Conductivity) | 0.001 μS minimum, auto ranging up to 4 significant digits |
| Range (Conductivity) | 0.001 μS/cm to 3000 mS/cm |
| Log Function Type | Automatic data logging with Auto-Read and Timed measure modes; manual data logging with Continuous m |
| Battery Type | 4 AA (included) |
| Relative Humidity Range | 5 to 85 %, non-condensing |
| Range (RDO) | 0.00 to 50.00mg/L |
| Dimensions (L x W x H) | 24cm x 10cm x 6.5cm (9.5 in. x 3.9 in. x 2.6 in.) |
| Accuracy (TDS) | 0.5% of reading ±1 digit |
| Temperature Selection | Manual or automatic with ATC temperature probe |
| Percent Saturation Range (RDO) | 0.0 to 500.0 % saturation |
| Keypad | Comprehensive with menu-specific function keys and dual purpose scroll/shortcut keys |
| Outputs | USB, RS232 |
| Temperature Range (English) | 22.0°F to 221.0° F |
| Range (Relative mV) | ±2000.0 mV |
| Calibration Points (pH) | 1 to 5 |
| Backlight Option | Yes (Selectable) |
| Percent Saturation Relative Accuracy (RDO) | ±2 % saturation ≤ 200 % saturation, ±10 % saturation > 200 % saturation |
| Range (Polarographic DO) | 0.00 to 90.00mg/L |
| Range (mV) | ±2000.0 mV |
| Accuracy (Barometer) | ±6mmHg |
| Range (ORP) | ±2000.0 mV |
| Methods | 10 per channel with password protection |
| Pressure Resolution | 1mmHg |
| Cell Constant | 0.001 to 199.9cm-1 |
| Temperature (Metric) Reference | 5, 10, 15, 20, 25°C |
| Range (pH) | -2 to 20 |
| TDS Factor Range | Linear (0.02 to 9.99) |
| Channels | 3 |
| Accuracy (pH) | ±0.002 |
| Range (ISE) | 0.0001 to 19900 with selectable units of ppm, Molar, mg/L, %, ppb or none |
| Range (Salinity) | 0.06 to 80.00 psu, 0.05 to 42.00 ppt |
| Resolution (RDO) | 0.01, 0.1mg/L |
| Temperature Compensation | Linear, nLFn (non-linear ultra pure water), nLFu (non-linear ultra pure degassed water), EP (off with warning) or off |
| Accuracy (Salinity) | 0.5% of reading ±1 digit |
| Resolution (Salinity) | 0.01 psu or 0.01 ppt minimum, auto ranging |
| Percent Saturation Resolution (RDO) | 0.1, 1 % saturation |
| Accuracy (Conductivity) | 0.5% of reading ±1 digit > 3 μS; 0.5% of reading ±0.01 μS ≤ 3 μS |
| Percent Saturation Relative Accuracy (Polarographic DO) | ±2 % saturation or ±2% of reading whichever is greater |
| Inputs | BNC (pH or ORP electrode), pin-tip (reference electrode), 8 pin MiniDIN (conductivity sensor with built-in temperature or ATC temperature probe), 9 pin MiniDIN (RDO optical or polarographic DO sensor with built-in temperature) |
| Weight (Metric) | 0.5 kg |
| Calibration Points (Conductivity) | Up to 5 |
| Temperature (English) Operating | 41°F to 113°F (ambient) |
| Resolution (Resistivity) | 1 ohm or 0.1 meg-ohm, auto ranging |
| Isopotential Point | 7.000pH |
| Accuracy (Polarographic DO) | ±0.2mg/L or ±2% of reading, whichever is greater |
| Accuracy (Resistivity) | 0.5% of reading ±1 digit |
| AC Adapter | Universal 50-60 Hz, 100-240 VAC power adapter (sold separately, Cat. No. 1010003) |
| Range (TDS) | 0.001 ppm to 200.0 ppt |
| Resolution (TDS) | 0.001 ppm minimum, auto ranging up to 4 significant digits |
| Calibration | pH with calibration editing option, ion concentration (ISE) with calibration editing option, relativ |
| Calibration Points | 1 point relative mV (RmV) mode, 1 point ORP mode |
| Alarm Output | High/low limit alarm, calibration due alarm |
| IP Rating | IP67 |
| Percent Saturation Resolution (Polarographic DO) | 0.1, 1 % saturation |
| Model | Orion Star A329 pH/ISE/mV/RmV/ORP/Conductivity/TDS/Salinity/Resistivity/RDO Optical/Dissolved Oxygen/Temperature Portable Meter |
| Weight (English) | 1.2 lb. |
| Temperature (Metric) Operating | 5°C to 45°C (ambient) |
| Temperature Range (Metric) | -5.0°C to +105.0°C |
| Percent Saturation Range (Polarographic DO) | 0.0 to 600.0 % saturation |
| Temperature Resolution | 0.1°C, 0.1°F |
| Accuracy (RDO) | ±0.1mg/L up to 8mg/L, ±0.2mg/L from 8 to 20mg/L, ±10% of reading up to 50mg/L |
Thermo Scientific™ Orion™ Double Junction Glass Bodied Combination pH Electrode
Capture accurate measurements of a variety of samples types, including solvents, with Orion glass body pH electrodes.
Thermo Scientific™ Orion™ ROSS™ Sure-Flow™ Thin Stem Epoxy Bodied Combination pH Electrode
Attain stable, drift-free measurements of challenging samples in narrow containers using a sure-flow electrode with its unique free-flowing liquid-to-liquid junction.
Mettler Toledo™ pH Sensor InLab™ Pure Pro-DES™
A glass body, combination pH electrode with integrated temperature sensor, DES sensor head, bridge electrolyte and a fixed glass sleeve junction. Designed for low-ion samples like ultra-pure water, deionized water
OHAUS™ Starter Series Electrode: STSURF 2-in-1 Flat pH Electrode
Use in combination with Starter bench and portable meters. OHAUS Starter Series Electrode: STSURF 2-in-1 Flat pH Electrodes need to work with STTEMP30 temperature electrodes for 0.01 pH accuracy.
Thermo Scientific™ Orion™ Single Junction Sure-Flow™ Epoxy Bodied Combination pH Electrode
Attain stable, drift-free measurements of challenging samples using a sure-flow electrode with its unique free-flowing liquid-to-liquid junction.