Electrochemical determination of L-arginine in leukemic blood samples based on a polyaniline-multiwalled carbon nanotube—magnetite nanocomposite film modified glassy carbon electrode

The present study reports an electrochemical biosensor for the rapid and selective detection of L-arginine in leukemic blood samples. The biosensor was fabricated using a nanocomposite (PANI/MWCNTs/Fe₃O₄) film modified glassy carbon electrode (GCE). The partially purified arginine deiminsae (ADI) enzyme from P. putida was immobilized on the modified GCE by cross linking with gluteraldehyde. The characterization and validation of the developed biosensor was performed by various electrochemical techniques including cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CA). The limit of detection for biosensor was determined to be as low as 20 μM based on a signal-to-noise ratio equal to three while employing a detection period of 10 s. A linear response for L-arginine was observed across the concentration range from 100 to 1000 µM with an R² value of 0.9987. The biosensor designed in the present study offers highly specific and sensitive analysis in normal and leukemic blood samples compared to previous reports in the literature. Therefore this device has excellent potential for nano-device fabrication for biomedical applications.