SPE biosensor for cholesterol in serum samples based on electrochemiluminescent luminol copolymer

Area of Science:

• Electrochemistry
• Biotechnology
• Analytical Chemistry

Background:

• Electrochemical biosensors are crucial for disease diagnosis.
• Hydrogen peroxide electrochemiluminescence (ECL) offers high sensitivity.
• Developing efficient ECL materials is key for advanced biosensing.

Purpose of the Study:

• To develop a novel ECL biosensor for cholesterol detection.
• To enhance the electrochemiluminescence of hydrogen peroxide using a novel copolymer.
• To immobilize cholesterol oxidase for specific cholesterol sensing.

Main Methods:

• Electropolymerization of a poly(luminol-3,3',5,5'-tetramethylbenzidine) copolymer on gold electrodes.
• Immobilization of cholesterol oxidase on the copolymer-modified screen-printed electrode using chitosan.
• Optimization of ECL detection conditions for cholesterol.

Main Results:

• The novel copolymer significantly enhanced hydrogen peroxide ECL.
• The developed ECL biosensor demonstrated a linear dynamic range of 2.4 × 10(-5)-1.0 × 10(-3)M for cholesterol.
• A low limit of detection (7.3 × 10(-6)M) and good precision (10.3% RSD) were achieved.
• Satisfactory results were obtained when analyzing total cholesterol in human serum samples.

Conclusions:

• The poly(luminol-3,3',5,5'-tetramethylbenzidine) copolymer is an effective material for ECL-based biosensing.
• The developed ECL biosensor provides a sensitive, rapid, and cost-effective method for cholesterol determination.
• This biosensor presents a viable alternative to conventional methods for clinical analysis.