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Certified sec. standard reference buffer solution

potassium dihydrogen phosphate/di-sodium hydrogen phosphate, pH 6.86 (25 °C), Certipur®

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certified reference material

Quality Level


complies with DIN 19266

product line



potassium dihydrogen phosphate/di-sodium hydrogen phosphate


6.86 (25 °C)


food and beverages
general analytical
industrial qc



storage temp.


General description

The certified secondary standard reference buffer solution (potassium dihydrogen phosphate/disodium hydrogen phosphate) is gravimetrically prepared using high-quality reagents in high-purity water. Its pH value is measured by differential potentiometry with two platinum hydrogen electrodes against primary certified reference materials from NIST & PTB. It is qualified using a 5-point calibration method, in accordance with DIN 19268, against certified primary reference standards as per DIN 19266.

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The buffer solution can be used to calibrate, qualify, and monitor pH measuring instruments and as a control for testing other buffer solutions.

Features and Benefits

  • Available in a sealed 100 mL high-density plastic bottle
  • Subjected to detailed stability studies as per ISO Guide 35
  • Product label carryies relevant information on order number, article description, lot number, expiry date and safety data, in accordance with ISO Guide 31
  • Accompanied with a detailed and batch-specific certificate of analysis (CoA) for an effective quality management system
  • Measured and qualified in an ISO/IEC 17025 and ISO 17034 accredited laboratory
  • Traceable to SRMs from NIST and primary certified reference standards from PTB

Analysis Note

pH-value: 6.861 - 6.867
For complete data see the enclosed certificate

Legal Information

CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany

Storage Class

12 - Non Combustible Liquids




Not applicable


Not applicable

Certificates of Analysis (COA)

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