Development and characterization of angiotensin I certified reference materials

Area of Science:

• Biochemistry
• Analytical Chemistry
• Clinical Diagnostics

Background:

• Angiotensin I (ANGI) is crucial for blood pressure regulation and homeostasis.
• Accurate ANGI measurement aids in diagnosing and treating various diseases.
• A standardized reference material is needed to validate diverse ANGI detection methods.

Purpose of the Study:

• To establish high-purity natural and isotope-labeled Angiotensin I (ANGI) certified reference materials.
• To ensure the accuracy, comparability, and reliability of ANGI measurements.
• To support method validation and interlaboratory comparisons in clinical diagnostics.

Main Methods:

• Characterization of natural and isotope-labeled ANGI using mass balance and quantitative nuclear magnetic resonance (qNMR).
• Determination of moisture (Karl Fischer), anion (ion chromatography), and inorganic elements (ICP-MS).
• Purity verification via isotope dilution mass spectrometry (IDMS) and labeling rate assessment (high-resolution liquid-mass spectrometry).

Main Results:

• Natural and labeled ANGI purities were determined as (0.8511 ± 0.041) g/g and (0.8696 ± 0.042) g/g, respectively.
• Labeling rates for 13C and 15N in double-labeled ANGI reached 98.98% and 99.43%.
• Established reference materials provide a reliable standard for ANGI quantification.

Conclusions:

• Development of high-purity natural and isotope-labeled ANGI reference materials.
• These materials enable accurate and comparable ANGI quantification for clinical applications.
• Supports quality control, method validation, and biomarker research in ANGI analysis.