TRIS Buffers – What electrodes can I use?

TRIS-buffers are used by biochemists to control pH in the physiological range (about 7 to 8 pH) because phosphates cause undesirable side reactions with the biological substances in their test samples. However, when pH measurements are to be made on these solutions, another type of “undesirable side reaction”, involving the…

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Do you have a datasheet for FermProbe Wetted Materials?

The FermProbe Double Junction Reference System All FermProbes have two built-in electrolyte chambers that act to protect and isolate the sensitive inner AgCl reference half-cell. This “double junction”, dual-chamber design effectively prevents the most common failure modes of pH electrodes in biopharmaceutical applications. Only the inner, smaller chamber contains silver…

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Why is my FermProbe turning brown?

The longer the electrode is exposed to high temperatures (above 100 degrees C) the darker it becomes. Likewise, the higher the temperature, the darker the color. This is normal. If the electrode can be calibrated, it’s OK to use it.

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Are there different types of ports?

The electrode housing is designed to hold and protect the pH electrode while inserting it into the bioprocess vessel. There are various types of side entry ports and different groups of housings to fit each port type. The size and make of the port must first be identified in order…

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How do I choose a housing style for my pH Electrode?

The electrode housing is designed to hold and protect the PH electrode while inserting it into the bioprocess vessel. There are various types of side entry ports and different groups of housings to fit each port type. The size and make of the port must first be identified in order…

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Do I want a Guarded or Unguarded Housing?

The electrode/housing assembly can accidentally “bump” into the 25 mm port when being installed. If the pH sensing glass bulb of the electrode is not protected by a housing bulb guard, the electrode can easily be shattered. A guarded housing design is often the engineer’s first choice when choosing an…

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Why would I choose a longer electrode length?

Sometimes the tank wall can become coated with a thick layer of viscous material that does not mix well with the rest of the media. If the pH sensing bulb of the electrode is located just a couple of inches inside the tank wall, the bulb might be smothered by…

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How should I clean a FermProbe?

FermProbe® Cleaning Procedures Remove Bulb Coating Protein Deposition Warm water bath with dish detergent Warm water bath with enzyme detergent (i.e. Terg-A-Zyme®) Scrub bulb and rinse Inorganic Scale Deposits Dip only the bulb of the electrode into 0.1N hydrochloric acid Rinse Organic Oil or Films Clean with acetone and rinse Rehydrate…

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How should I compare grab sample and on-line pH measurements?

Preface: There are potential problems when comparing a laboratory pH analysis or grab sample measurement with on-line pH measurement. In order to obtain reliable data when making comparisons between these two types of pH measurements, it is essential that the proper apparatus and procedures be incorporated as outlined below: Apparatus:…

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