Urea biosensors based on PVC membrane containing palmitic acid.

Area of Science:

• Biotechnology
• Electrochemistry
• Biosensor Development

Background:

• Urea detection is crucial for diagnosing various medical conditions.
• Existing biosensors face challenges in sensitivity and stability.
• Development of efficient enzyme immobilization techniques is essential for biosensor performance.

Purpose of the Study:

• To develop and characterize a novel urea biosensor.
• To compare the performance of urease immobilized on palmitic acid-PVC versus carboxylated PVC membranes.
• To evaluate the biosensor's applicability for urea determination in biological samples.

Main Methods:

• Immobilization of urease onto poly(vinylchloride) (PVC) ammonium membrane electrodes using four different procedures.
• Incorporation of nonactine as an ammonium-ionophore and palmitic acid into the PVC membrane.
• Investigation of analytical characteristics including pH, buffer concentration, temperature, enzyme concentration, stirring rate, and immobilization methods.
• Assay of urea in serum using the standard addition method.

Main Results:

• The urea biosensor prepared with palmitic acid-PVC membranes exhibited significantly better performance than those based on carboxylated PVC.
• Optimal conditions for pH, buffer concentration, temperature, and enzyme concentration were determined.
• The biosensor demonstrated a defined linear working range and sensitivity.
• Successful urea assay in human serum samples was achieved.

Conclusions:

• The developed urea biosensor offers enhanced performance due to the use of palmitic acid-modified PVC membranes.
• The biosensor is a viable tool for accurate urea quantification in clinical samples.
• This study highlights the importance of enzyme immobilization strategies in biosensor design.