Enzymatic rotating biosensor for ciprofloxacin determination

Area of Science:

• Analytical Chemistry
• Biochemistry
• Electrochemistry

Background:

• Enzymatic systems offer high sensitivity for analyte detection.
• Catechol-mediated reactions coupled with electrochemical detection are valuable analytical tools.
• Accurate quantification of pharmaceuticals like ciprofloxacin (CF) is crucial.

Purpose of the Study:

• To develop and validate a sensitive biosensor for ciprofloxacin detection.
• To investigate the use of immobilized horseradish peroxidase (HRP) and catechol in a rotating biosensor system.
• To assess the performance of the biosensor for analyzing pharmaceutical samples.

Main Methods:

• On-line interfacing of a rotating biosensor with continuous flow processing.
• Immobilization of HRP on a rotating disk for catechol oxidation in the presence of hydrogen peroxide.
• Electrochemical detection of catechol reduction products at a glassy carbon electrode (-200mV).

Main Results:

• Ciprofloxacin reacted with catechol via Michael addition, forming piperazine-quinone derivatives and reducing peak current.
• The highest response for CF was observed around pH 7.
• The method determined CF concentration in the range of 0.02-65µM (r=0.999) with a detection limit of 0.4nM.
• The biosensor processed up to 25 samples per hour.

Conclusions:

• The HRP-rotating biosensor provides a highly sensitive and efficient method for ciprofloxacin determination.
• The developed analytical method is suitable for application in pharmaceutical sample analysis.
• The system demonstrates the utility of enzymatic biosensors for rapid drug quantification.