Can you trust your buffer solution?

GMP, GLP, ISO 9001, EN 45000, Calibration, Verification, Traceability, and Certification from an accredited organization: Key words those are increasingly important. The calibration of pH and Redox electrodes has never been easy. All calibration procedures assume that the labelled values of the calibration buffers are correct. But buffer values can change over time and so can your results

A complete range of patented buffer solutions provides never before achieved pH stability. Hamilton guarantees DURACAL pH buffers for 5 years after the date of manufacture. The pH 9.21 and pH 10.01 buffers are even stable in air. See the diagram below for details. High buffering capacity provides rapid, stable calibration. Preservatives are added to prevent microbial and mold growth.

Traceability

An important issue for the production of Certified Reference Material is to ensure the traceability through an unbroken chain of comparisons to reference mate­rial of the highest metrological quality (Primary Reference Material).

• Closed Loop Traceability: Unlike other manufacturers where only a top-down traceability is applied, Hamilton is work­ing with circular or closed loop traceability. The closed loop traceability ensures the users of Hamilton DURACAL buffer a unique reliability!

• Top-down traceability: At Hamilton, the pH value of DURACAL buffers is de­termined by comparison against two Sec­ondary Reference Buffer Solutions. These are purchased from accredited suppliers for Secondary Reference Materials. The so­lutions themselves are compared against Primary Reference Solutions from PTB¹⁾ or NIST ²⁾.

• Bottom-up traceability: To ensure the highest possible accuracy and full reliability of the pH value, a representa­tive number of samples from every single production lot is sent to a German DKD³⁾ laboratory (DKD-K-06901) for an external, independent and impartial verification. In this laboratory, the DURACAL samples are compared against Secondary Reference Solutions from DKD-K-06901.

The Secondary Reference Solutions are of course compared against Primary Refer­ence Solutions from PTB. At this stage, the loop is closed: the PTB Primary Refer­ence Solution is the starting and ending point of the traceability loop. DKD provides Hamilton with a calibration certificate for every DURACAL production lot.