Electrospun hemoglobin microbelts based biosensor for sensitive detection of hydrogen peroxide and nitrite

Area of Science:

• Electrochemistry
• Biosensors
• Materials Science

Background:

• Hemoglobin (Hb) is a crucial protein for oxygen transport.
• Developing efficient biosensors requires stable and active immobilization of biomolecules.
• Direct electrochemistry of Hb offers potential for mediator-free biosensing.

Purpose of the Study:

• To develop a highly porous hemoglobin (Hb) microbelts-based biosensor.
• To investigate the electrochemical properties of Hb microbelts for sensing applications.
• To evaluate the performance of the Hb microbelts biosensor for detecting hydrogen peroxide and nitrite.

Main Methods:

• Direct electrospinning of Hb onto a glassy carbon (GC) electrode without immobilization matrix.
• Characterization using Ultraviolet-visible (UV-Vis) spectroscopy and Fourier transform infrared (FTIR) spectroscopy.
• Electrochemical evaluation using cyclic voltammetry and amperometry.

Main Results:

• Hb retained its native structure in electrospun microbelts.
• Hb microbelts modified GC electrode exhibited enhanced electrocatalytic activity for H2O2 and nitrite reduction.
• The amperometric biosensor demonstrated fast response, wide dynamic range, and low detection limits (0.61 µM for H2O2, 0.47 µM for nitrite).
• Superior apparent Michaelis-Menten constants (K(M,app)) were observed (0.093 mM for H2O2, 0.713 mM for nitrite).

Conclusions:

• Electrospun Hb microbelts significantly enhance the direct electrochemistry of Hb.
• The developed biosensor is effective for sensitive and selective detection of H2O2 and nitrite.
• This approach holds great potential for mediator-free biosensor applications.