Functionality of dielectrophoretically immobilized enzyme molecules.

Area of Science:

• Biotechnology
• Nanotechnology
• Electrochemistry

Background:

• Enzyme immobilization is crucial for biosensor development.
• Traditional methods can alter enzyme activity or require chemical modification.
• Nanoelectrode arrays offer high surface area for immobilization.

Purpose of the Study:

• To immobilize horseradish peroxidase (HRP) on nanoelectrode arrays using dielectrophoresis (DEP).
• To demonstrate the preservation of HRP enzymatic activity after DEP immobilization.
• To explore DEP as a novel method for creating bioactive surfaces for biosensing.

Main Methods:

• Horseradish peroxidase (HRP) was immobilized on nanoelectrode arrays via alternating current dielectrophoresis (DEP).
• Enzyme function was assessed by oxidizing dihydrorhodamine 123 to rhodamine 123 using hydrogen peroxide.
• Fluorescence microscopy was used for localization of enzyme and product.
• Experimental parameters were optimized for even enzyme distribution and efficiency.

Main Results:

• DEP successfully immobilized HRP onto nanoelectrode arrays.
• Immobilized HRP retained enzymatic activity, evidenced by rhodamine 123 production.
• Fluorescence microscopy confirmed enzyme and product localization.
• Optimized DEP parameters ensured even enzyme distribution and high efficiency.

Conclusions:

• Dielectrophoresis (DEP) is an effective method for immobilizing enzymes like HRP while preserving their activity.
• DEP eliminates the need for chemical modification of enzymes for immobilization.
• This technique offers a novel approach for preparing bioactive surfaces for biosensing applications.