Binding study of lysozyme with Al(III) using chemiluminescence analysis

Area of Science:

• Analytical Chemistry
• Biochemistry
• Pharmacokinetics

Background:

• Accurate quantification of aluminum (Al(III)) in biological samples is crucial for understanding its physiological effects and toxicity.
• Existing methods for Al(III) detection may lack the sensitivity or applicability for real-time monitoring in complex matrices like saliva.

Purpose of the Study:

• To develop and validate a sensitive flow injection-chemiluminescence (FI-CL) method for the detection of Al(III) using luminol and lysozyme.
• To investigate the binding interaction between lysozyme and Al(III) to establish the basis for the chemiluminescence enhancement.
• To apply the developed method for the continuous monitoring of Al(III) in human saliva after oral administration of aluminum hydroxide.

Main Methods:

• Utilized luminol as a luminescence probe in a flow injection-chemiluminescence system.
• Employed lysozyme as a binding agent to enhance the chemiluminescence signal in the presence of Al(III).
• Determined the binding constant (K) and number of binding sites (n) using a proposed interaction model.

Main Results:

• A significant enhancement of chemiluminescence intensity was observed with increasing Al(III) concentration, exhibiting linearity from 0.3–30.0 pg mL⁻¹.
• The method achieved a low detection limit of 0.1 pg mL⁻¹ for Al(III).
• Successful application in monitoring picogram levels of Al(III) in human saliva, with peak concentrations of 101.2 ng mL⁻¹ at 3.0 hours post-ingestion and calculated pharmacokinetic parameters (ka, k, t½).

Conclusions:

• The developed FI-CL method offers a sensitive, reliable, and continuous approach for quantifying Al(III) in human saliva.
• The study provides insights into the pharmacokinetics of Al(III) absorption and elimination following oral intake of aluminum hydroxide.
• This technique holds potential for clinical and research applications requiring precise Al(III) level monitoring.