Investigating aluminium citrate speciation by high performance liquid chromatography

Area of Science:

• Analytical Chemistry
• Environmental Science
• Toxicology

Background:

• Aluminum (Al) toxicity is species-dependent.
• Separation of small molecular weight toxic Al complexes is currently limited.
• Developing analytical methods for Al speciation is crucial for understanding its toxicity.

Purpose of the Study:

• To evaluate High-Performance Liquid Chromatography (HPLC) coupled with atomic absorption spectroscopy for separating aluminum citrate from other Al species.
• To investigate the potential of various HPLC stationary phases and mobile phases for Al complex separation.

Main Methods:

• HPLC separation was combined with atomic absorption spectroscopic detection of Al.
• Nine different HPLC stationary phase supports and numerous mobile phases were examined.
• Specific mobile phases and columns (Cyclobond III, cyano) were tested for Al citrate and Al desferrioxamine retention.

Main Results:

• The Cyclobond III and cyano columns showed initial promise for Al citrate separation.
• Al citrate was retained for approximately 9 minutes on Cyclobond III with a specific mobile phase.
• The cyano column offered better Al citrate recovery (up to 65%) but limited retention time manipulation.

Conclusions:

• Current HPLC methods show potential but lack the reproducibility and sufficient retention for routine quantitation of Al citrate in biological samples.
• Further optimization of stationary and mobile phases is needed for effective separation of toxic Al species.
• The study highlights the challenges in developing analytical techniques for complex aluminum speciation.