Electrodes for pH measurement Which electrode for which application? Application Specifics Electrode Order no. Application Specifics Electrode Order no. Standard laboratory, various samples, General Viscotrode 6.0239.100 Unitrode 6.0260.010 Detergents, pH 0...14, T = 0...100 °C General surfactants Samples with pH >10 Profitrode 6.0255.100 Routine analysis in similar samples, Ecotrode Gel 6.0221.600 Bleaching & dye baths Profitrode 6.0255.100 pH 1...11 Leather, Dampening solutions (offset printing), glue Unitrode 6.0260.010 Demineralized, drinking and sea water, paper, Water Aquatrode Plus 6.0257.600 Leather, paper, textiles (surface measurement) Flat-membrane 6.0256.100 weakly buffered solutions textile industry Washing liquors Viscotrode 6.0239.100 Waste water General Unitrode 6.0260.010 Dye baths, ink, wood stain, lacquers Profitrode 6.0255.100 Sulfide-containing waste water Profitrode 6.0255.100 Paints, Dispersions, emulsions, resins, Surface measurement or aqueous Unitrode 6.0260.010 Soil samples Flat-membrane 6.0256.100 lacquers, suspensions suspensions solvents Paint (surface) Flat-membrane 6.0256.100 Culture media, small volume samples Biotrode 6.0224.100 Non-aqueous, polar solvents EtOH-Trode 6.0269.100 Fertilizers Unitrode 6.0258.600 Agriculture, Electroplating, General Profitrode 6.0255.100 plant breeding Liquid manure Profitrode 6.0255.100 metal Acidic electroplating baths Unitrode 6.0258.600 Nutrient solutions Viscotrode 6.0239.100 processing Cutting-oil emulsions Viscotrode 6.0239.100 Protein-containing solutions Porotrode 6.0235.200 Concentrated acids Profitrode 6.0255.100 General Unitrode 6.0258.600 Food, Photographic baths, fixative solutions Profitrode 6.0255.100 Protein-containing food, beer Porotrode 6.0235.200 stimulants Emulsions, suspensions, dispersions Unitrode 6.0260.010 Penetration measurement (dough, cheese, meat) Spearhead 6.00226.600 Polymer dispersions (water-based dispersion Drinking water Aquatrode Plus 6.0257.600 paints and adhesive dispersions on basis of Ecotrode Gel 6.0221.600 Juices, wine, spirits Unitrode 6.0260.010 acrylic acid esters and styrene) Creams, liquid formulations, medicinal syrups Special Viscotrode 6.0239.100 Samples at pH >12 Unitrode 6.0258.600 applications Pharmaceutical mouthwashes, raw materials Temperature 80...100 °C Unitrode (Idrolyte) 6.0258.600 industry, Dialysis solutions, urine Unitrode 6.0260.010 Ion-deficient solutions, weakly buffered solutions Aquatrode Plus 6.0257.600 biology Gastric juice, serum, small-volume samples Biotrode 6.0224.100 Non-aqueous, polar solvents EtOH-Trode 6.0269.100 Infusion solutions Aquatrode Plus 6.0257.600 Penetration measurement Spearhead 6.00226.600 Protein-containing solutions Porotrode 6.0235.200 Protein-containing solutions Porotrode 6.0235.200 Shampoos, emulsions, shower gels, lotions, Viscotrode 6.0239.100 Biotrode 6.0224.100 Small volume samples Cosmetics perfumes Flat-membrane 6.0256.100 Make-up Microelectrode 6.0234.100 Surface measurements Flat-membrane 6.0256.100 Skin (surface measurement) Flat-membrane 6.0256.100 Biofuels EtOH-Trode 6.0269.100 www.pH-measurement.com Practical tips, care and maintenance of pH electrodes Unitrode Ecotrode Gel Spearhead Flat-membrane Aquatrode Plus Profitrode Viscotrode Biotrode pH electrode Porotrode pH electrode EtOH-Trode Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass Combined pH glass electrode, fixed ground- electrode, twin-pore electrode, fixed electrode, flexible electrode, flexible electrode, plied Pt-wire electrode, twin-pore electrode, ceramic electrode, fixed electrode, fixed joint diaphragm. diaphragm. ground-joint diaphragm. ground-joint dia-ground-joint dia- diaphragm. diaphragm. capillary diaphragm. ground-joint diaphragm. ground-joint dia- • Very low alkali error • For routine • For low-conductivity phragm. phragm. • For small-volume • For measurement • For protein-containing • For pH-measurement phragm. • Insensitive to measurements in or weakly buffered • For difficult matrices • For viscous, protein samples in semi-solid samples or viscous samples on surfaces • For pH-measurements contamination similar samples solutions • Very easy to clean or sulfide-containing • For protein-containing • Maintenance-free • Reference electrolyte: (e.g. skin, leather, in EtOH and other • High-temperature • With lifetime • Very rapid response • Double-junction solutions samples and samples reference electrolyte Porolyte2) paper, textiles) polar solvents resistance indicator • Insensitive to construction • Easy-to-clean containing organic (gel) 6.2318.000 • Very rapide response • Double-junction • Maintenance-free contamination diaphragm solvents • Very easy to clean • Very easy to clean • For measurement construction Ordering info reference electrolyte • Shaft diameter 3 mm of small-volume 6.0259.100 (gel) Ordering info Ordering info • Reference electrolyte: samples without cable, 6.0253.100 All without cable, Idrolyte1) 6.2308.040 plug-in head G without cable, plug-in head G 6.0260.010 plug-in head G 6.0255.100 (with Pt1000), Ordering info Ordering info Ordering info Ordering info Ordering info Ordering info Ordering info 6.0257.600 (fitting length: 113 mm) fixed cable 6.0221.100 6.0239.100 6.0224.100 6.0226.100 6.0235.200 6.0256.100 6.0269.100 (with Pt1000), without cable, 6.0255.110 without cable, without cable, without cable, without cable, without cable, without cable, 6.0258.600 without cable, plug-in head G (fitting length: 170 mm) (with Pt1000), without plug-in head G plug-in head G plug-in head G plug-in head G plug-in head G plug-in head G plug-in head U cable, plug-in head U 6.0221.600 6.0255.120 6.00226.600 iAquatrode Plus: (with NTC), without (fitting length: 310 mm) (with Pt1000), iUnitrode: 6.0278.3003) 6.0277.3003) cable, plug-in head U dProfitrode: without cable, dUnitrode: 6.00200.3004) dAquatrode Plus: 6.00204.3004) plug-in head U 6.00202.3004) Use 6.2308.040 Store in c(KCl) = sat. Store in 6.2323.000 Store in bridge Store in 6.2323.000 Store in 6.2308.040 Store in 6.2308.000 Store in 6.2323.000 Store in 6.2323.000 If reference electrolyte Idrolyte1) as reference 6.2308.000 storage solution only. electrolyte. storage solution. Idrolyte1). KCl sat. storage solution. storage solution. is c(KCl) = 3 mol/L electrolyte for measure- Do not wipe electrode. Do not wipe electrode. Do not wipe electrode. Do not wipe electrode. Do not wipe electrode. Rinse with water or Rinse with water or Add a small drop of store in 6.2323.000 ment at temperatures ethanol to remove ethanol to remove dist. water on the storage solution. 80...100 °C or to Rinse with water/ For cleaning/care For cleaning/care For cleaning/care Do not clean the contamination. contamination. surface to be measured. Do not wipe electrode. suppress protein ethanol to remove 6.2325.000 pHit kit 6.2325.000 pHit kit 6.2325.000 pHit kit diaphragm mechani- precipitation by KCl. contamina tion. is recommended. is recommended. is recommended. cally because the Do not remove Do not wipe electrode. Do not wipe electrode. For cleaning/care platinum wire may contamination in Slightly lift ring-shaped Slightly lift ring-shaped For cleaning/care For cleaning/care 6.2325.000 pHit kit Do not wipe electrode. be damaged. pinhole diaphragm sleeve for cleaning sleeve for cleaning 6.2325.000 pHit kit 6.2325.000 pHit kit is recommended. Unitrodes filled with mechanically or with ground-joint dia- ground-joint dia- For cleaning/care is recommended. is recommended. c(KCl) = 3 mol/L a needle. The gel phragm. phragm. 6.2325.000 pHit kit should be solely stored electrolyte might be Loosen stuck ground- Loosen stuck ground- is recommended. in 6.2323.000 damaged. joint by immersing in joint by immersing in storage solution. Remove electrode hot water for a few hot water for a few For cleaning/care slowly from sample to minutes to dissolve minutes to dissolve 6.2325.000 pHit kit avoid underpressure adhering material. adhering material. is recommended. in the gel electrolyte. Spare ground-joint diaphragm for Profitrodes 6.0255.1X0: order no. 6.1243.020 8.109.6004EN – 2019-04 1) Idrolyte is a glycerol-based electrolyte whose ion activity corresponds to that of c(KCl) = 3 mol/L. 3) An iConnect 2.854.0010 is required to connect an iTrode to the instrument. 2) Porolyte is a KCl solution that has been gelled by polymerization and is used in electrodes with a capillary diaphragm (Porotrode). 4) dTrodes can only be used with a digital measuring module at an OMNIS Titrator / Titration Module.