Simultaneous determination of L- and D-carnitine using a sequential injection analysis/amperometric biosensors system

Area of Science:

• Analytical Chemistry
• Biotechnology
• Biochemistry

Background:

• Carnitine enantiomers (L- and D-carnitine) play distinct biological roles.
• Accurate and simultaneous determination of these enantiomers is crucial for various applications, including pharmaceutical quality control and metabolic studies.
• Existing analytical methods may lack the efficiency or precision required for real-time monitoring.

Purpose of the Study:

• To develop and validate a sequential injection analysis (SIA) system for the simultaneous determination of L- and D-carnitine.
• To utilize amperometric biosensors for sensitive and selective detection of carnitine enantiomers.
• To enable on-line process control for monitoring the enantiopurity of carnitine.

Main Methods:

• Development of an SIA system incorporating amperometric biosensors.
• Immobilization of L-amino acid oxidase and horseradish peroxidase (HRP) for L-carnitine detection.
• Immobilization of D-amino acid oxidase and HRP for D-carnitine detection.
• Optimization of the SIA system for precision, accuracy, and low reagent consumption.

Main Results:

• The SIA system achieved simultaneous determination of L- and D-carnitine with high precision and accuracy.
• Biosensors exhibited linear concentration ranges from pmol/L to nmol/L with very low limits of detection.
• The system demonstrated reliable on-line process control for carnitine enantiopurity at a rate of 34 samples per hour.

Conclusions:

• The developed SIA system with amperometric biosensors is a robust and efficient tool for simultaneous L- and D-carnitine analysis.
• This method is suitable for on-line monitoring and quality control of carnitine enantiopurity.
• The system's advantages include high throughput, low sample and buffer consumption, and excellent analytical performance.