Buffer solution

General description
The buffer solution (citric acid/sodium hydroxide/hydrogen chloride) is gravimetrically prepared using high-quality reagents in high-purity water. It is quality controlled and qualified in an ISO/IEC 17025 accredited calibration lab. Its pH value of 4.00 at 20°C is qualified using a combined glass electrode following a 5-point calibration method, in accordance with DIN 19268, against certified primary reference standards as per DIN 19266, IUPAC, NIST, USP, and Ph. Eur.

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Application
It is used in analytical procedures for calibration, qualification, and monitoring of pH measuring instruments and as a control for testing other buffer solutions.
Features and Benefits
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
Ready-to-use solution available in a sealed bottle and an innovative Titripac® packaging for positive environmental impact due to reduced waste generation
Long-lasting with a shelf life of 3 years
Accompanied with a batch-specific and detailed certificate of analysis (CoA) for an effective audit
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany
Titripac is a registered trademark of Merck KGaA, Darmstadt, Germany