Mixed urease/amphiphile LB films and their application for biosensor development.

Area of Science:

• Biotechnology
• Biosensor Technology
• Surface Chemistry

Background:

• Urea detection is crucial for various applications, including environmental monitoring and clinical diagnostics.
• Enzymatic field-effect transistors (ENFETs) offer a promising platform for sensitive and selective analyte detection.
• Developing stable and efficient enzyme immobilization techniques is key to improving ENFET performance.

Purpose of the Study:

• To determine the optimal conditions for creating a stable mixed urease/octadecylamine (ODA) film at the air-water interface.
• To investigate the efficient transfer of this film onto a pH-ISFET surface.
• To characterize the performance of the resulting urea enzymatic field-effect transistor (ENFET).

Main Methods:

• Formation and characterization of a mixed urease/octadecylamine (ODA) film at the air-water interface.
• Transfer of the ODA-urease film onto a hydrophobized pH-ISFET surface.
• Electrochemical and device performance measurements of the fabricated urea ENFET.

Main Results:

• Optimal conditions for a stable urease/ODA film formation were established.
• The film was successfully transferred to the pH-ISFET, creating a functional urea ENFET.
• The urea ENFET demonstrated a detection limit of 0.2 mM, a response time of 15 seconds, and a dynamic range of 0-20 mM.

Conclusions:

• A stable mixed urease/octadecylamine film can be effectively prepared and utilized for urea detection.
• The developed urea ENFET exhibits excellent sensitivity, rapid response, and a wide dynamic range.
• This work presents a robust method for fabricating high-performance enzymatic biosensors for urea monitoring.