Polythiophene synthesis coupled to quartz crystal microbalance and Raman spectroscopy for detecting bacteria

Area of Science:

• Electrochemistry
• Polymer Science
• Biosensor Technology

Background:

• Conductive polymers offer versatile platforms for biosensor development.
• Immobilization of biomolecules is crucial for sensor specificity and sensitivity.
• Para-benzenesulfonyl chloride groups provide reactive sites for covalent bioconjugation.

Purpose of the Study:

• To synthesize a novel polythiophene with para-benzenesulfonyl chloride groups via an electrochemical method.
• To immobilize Protein A and antibodies onto the conductive polymer for bacteria detection.
• To evaluate the performance of the developed biosensor for pathogenic bacteria detection.

Main Methods:

• Electrochemical synthesis of polythiophene.
• Covalent immobilization of Protein A and antibodies.
• In situ monitoring using cyclic voltammetry, quartz crystal microbalance, and Raman spectroscopy.
• Detection of Salmonella enterica paratyphi.

Main Results:

• The synthesized polythiophene demonstrated high reactivity for covalent biomolecule binding.
• Successful successive immobilization of Protein A and antibodies was achieved.
• The conductive polymer platform exhibited significantly higher antibody recognition compared to gold surfaces.
• The biosensor successfully detected Salmonella enterica paratyphi.

Conclusions:

• The electrochemically synthesized polythiophene is a highly effective platform for biomolecule immobilization.
• The developed biosensor shows great potential for sensitive and specific detection of pathogenic bacteria.
• This approach offers a simple and cost-effective strategy for designing advanced immunocapture sensors.