Polyaniline Langmuir-Blodgett film based cholesterol biosensor

Area of Science:

• Biotechnology
• Biosensor Development
• Electrochemistry

Background:

• Cholesterol monitoring is crucial for cardiovascular disease management.
• Developing sensitive and reliable cholesterol biosensors is an ongoing research area.
• Langmuir-Blodgett (LB) films offer a platform for controlled immobilization of biomolecules.

Purpose of the Study:

• To covalently link cholesterol oxidase (ChOx) to polyaniline-stearic acid (PANI-SA) LB monolayers.
• To develop and characterize a novel ChOx/PANI-SA LB film/ITO bioelectrode for cholesterol detection.
• To evaluate the performance of the developed bioelectrode for cholesterol quantification.

Main Methods:

• Preparation of ChOx/Glu/PANI-SA LB films on indium-tin-oxide (ITO) coated glass.
• Characterization using Fourier Transform Infrared spectroscopy (FT-IR), cyclic voltammetry, and scanning electron microscopy (SEM).
• Performance evaluation using linear sweep voltammetry (LSV) for cholesterol concentration measurements.

Main Results:

• The developed bioelectrode exhibited linearity for cholesterol concentrations ranging from 25 to 400 mg/dL.
• Sensitivity was determined to be 88.9 nA mg(-1) dL with a high correlation coefficient (0.9988).
• A low Michaelis-Menten constant (1.21 mM) indicated enhanced interaction between immobilized ChOx and cholesterol.

Conclusions:

• The ChOx/PANI-SA LB film/ITO bioelectrode is a promising platform for sensitive and accurate cholesterol detection.
• The PANI-SA LB film facilitates effective immobilization and enhances the enzyme's interaction with cholesterol.
• This biosensor design offers potential for improved clinical diagnostics of hypercholesterolemia.