English
General description
The red-colored citric acid/sodium hydroxide/hydrogen chloride buffer solution is gravimetrically prepared using high-quality reagents, in accordance with DIN EN ISO/IEC 17025, at a registered calibration laboratory. Its pH value of 4.00 at 20°C is measured following a 5-point calibration method, using a combined glass electrode. The measurement is made following DIN 19268 using reference buffer solutions compliant to DIN 19266, NIST, IUPAC, Ph. Eur, and USP. Its pH value is strongly dependent on the temperature and therefore a constant temperature must be maintained during its use.
Please visit ISO certificates and Site Quality Self-Assessments to access the current certificates of accreditation.
Download your certificate at http://www.sigma-aldrich.com to view certified values, including uncertainty and expiry date.
Application
The buffer solution is meant to be used as a calibration standard for pH measuring instruments or pH electrodes and as a control for measuring the pH of other solutions.
Features and Benefits
Measured and qualified at an ISO/IEC 17025 and ISO 17034 accredited laboratory
Directly traceable to secondary reference standard from NIST and primary certified reference standard from PTB
Ready-to-use solution
Available in a sealed plastic bottle and sustainable Titripac® packaging for a reduced waste generation
Accompanied with a detailed and batch-specific certificate of analysis (CoA) for an effective audit
Product label follows the ISO Guide 31 and contains information about ordering number, article description, lot number, safety data, and expiry date
Packaging material subjected to comprehensive stability studies as per ISO Guide 35
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany
Titripac is a registered trademark of Merck KGaA, Darmstadt, Germany
