Sub-femtomolar capacitance-based biosensing of kanamycin using screen-printed electrodes coated with redox-active...

Area of Science:

• Biosensor technology
• Electrochemical analysis
• Food safety applications

Background:

• Antibiotic residues, like kanamycin, pose risks to consumer health and food safety.
• Sensitive and reliable detection methods are crucial for monitoring these residues.

Purpose of the Study:

• To develop an ultrasensitive capacitance-based biosensor for detecting kanamycin.
• To achieve label-free detection of kanamycin at sub-femtomolar concentrations.

Main Methods:

• Fabrication of a melanin-like polymeric film (MLPF) on gold nanoparticles (AuNPs) modified electrodes via potential-pulse-assisted method.
• Electrochemical polymerization of dopamine and kanamycin aptamer for MLPF formation.
• Label-free detection using electrochemical impedance spectroscopy to monitor pseudocapacitive property variations.

Main Results:

• Achieved a wide linear response for kanamycin detection from 1 fM to 100 pM.
• Demonstrated a remarkable limit of detection of 0.3 fM (S/N=3).
• Successfully applied the biosensor for kanamycin detection in milk samples with good recovery.

Conclusions:

• The developed aptasensor is a reliable and efficient tool for detecting trace kanamycin levels.
• This technology holds significant promise for antibiotic residue determination and ensuring dairy product safety.
• Contributes to safeguarding consumer health and maintaining high food safety standards.