Determination of K, Na, and Zn in Albumin Using Flame AAS

Determination of K, Na, and Zn in Albumin Using Flame AAS

Significance of the Topic

The accurate measurement of potassium, sodium and zinc in albumin is critical for clinical diagnostics and biochemical research. Monitoring these ions in protein matrices supports understanding of physiological functions, drug transport and enzyme activity. Reliable methods enable quality control in pharmaceutical and clinical laboratories.

Objectives and Study Overview

This application study aimed to develop and validate a flame atomic absorption spectrometry method for quantifying K, Na and Zn in albumin samples. Key goals included achieving high accuracy, repeatability and sensitivity within a streamlined workflow using standard software settings.

Methodology and Used Instrumentation

Sample Preparation

• Albumin samples at 25% concentration were diluted according to expected ion levels.
• Standards and quality controls prepared with trace metal grade acetic acid in deionized water.
• Calibration range from blank to 1 mg/L for all elements.

Instrumentation

• Agilent 240 FS double-beam flame AA spectrometer.
• Reflective optics and Czerny-Turner monochromator (185–900 nm) with holographic grating.
• Fully programmable flame controller supporting air/acetylene and nitrous oxide/acetylene flames.
• Automated lamp turret for multi-element analysis, high-speed deuterium background correction.
• PTFE nebulizer and spraychamber with adjustable impact bead for corrosion resistance.

Analytical Conditions

• Sodium and potassium measured in emission mode; zinc in absorption mode with D2 correction.
• Bandpass set to 0.2–1.0 nm, fuel flow 2 L/min, triplicate readings.

Main Results and Discussion

Calibration and Quality Control

• Linear calibration curves through the origin with correlation coefficients ≥ 0.998.
• Method detection limits: Na 0.008 mg/L, K 0.009 mg/L, Zn 0.001 mg/L.
• QC recoveries within 99–103% both after calibration and at run end.

Sample Analysis

• Measured concentrations aligned closely with customer estimates (RSD ≤ 0.8%).
• Spike recoveries between 100–107%, duplicates within 5% variability.

These results demonstrate method accuracy, precision and suitability for albumin matrices.

Benefits and Practical Applications

The presented flame AAS approach offers a cost-effective, rapid and robust protocol for routine laboratory analysis. The automated instrument features and software cookbooks simplify operation and reduce setup time, making it ideal for clinical, pharmaceutical and research environments requiring high throughput and reliable ion quantification.

Future Trends and Opportunities

Advancements in miniaturized atomizers, coupling with high-resolution spectrometers and integration with automated sample handling promise further improvements in sensitivity and productivity. Emerging software algorithms for spectral deconvolution and real-time quality monitoring will enhance data reliability and expand applications to more complex protein and biological matrices.

Conclusion

The Agilent 240 FS flame AAS method delivers accurate, repeatable measurements of K, Na and Zn in albumin. Calibration linearity, low detection limits and robust QC performance affirm its suitability for clinical and industrial laboratories. Automated controls and established software protocols facilitate efficient routine analysis.

Reference

L H J Lajunen and P Peramaki Spectrochemical Analysis by Atomic Absorption and Emission Royal Society of Chemistry Cambridge 2004
US Department of Health and Human Services National Institutes of Health website Accessed July 10 2006