ELECTROCHEMICAL DETECTION OF BRAIN-DERIVED NEUROTROPHIC FACTOR BY MOLECULARLY-IMPRINTED POLYMER ON SCREEN-PRINTED ELECTRODE

Brain-derived neurotrophic factor (BDNF) is a member of the family of protein neurotrophins that selectively affects the development, maintenance and survival of neurons, and its abnormal level in the blood may be associated with a number of neurodegenerative diseases (ND). Serum concentration of a BDNFspecific NF could be a potential biomarker for the early-stage diagnosis of ND.¹ Molecularly Imprinted Polymer (MIP) based biosensors for BDNF detection might simplify and reduce the cost for the NF detection assays. MIP film synthesized on screen-printed electrodes (SPE) provides a considerable option for obtaining a lab-on-chip analytical device. In this study BDNF-MIP was generated on the gold surface of SPE by electropolymerization of m-phenylenediamine. The BDNF was previously immobilized onto the gold surface via the linker having the cleavable S-S bond. The growth of poly(m-phenylenediamine) (PmPD) film was controlled precisely by the electrical charge dosage and its thickness was optimized in order to avoid irreversible entrapment the immobilized BDNF. To form molecular imprints, BDNF was removed from the polymer by treatment in 0.1 M ethanolic solution of mercaptoethanol as an agent cleaving the S-S bond in the linker system followed by the use of acetic acid 5%. The morphology of the BDNF-MIP film surface was characterized by scanning electron microscopy. The binding affinity and selectivity of the BDNF-MIP films toward the target were determined by means of electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The electrochemical measurements demonstrated the ability of the prepared BDNF-MIP film to discriminate the target protein among the interferents.

References

1. Ventriglia, M., et al.,2013 Serum brain-derived neurotrophic factor levels in different neurological diseases. BioMed research international.: p. 901082.