MOLECULARLY IMPRINTED POLYMER-BASED SENSOR FOR LABEL-FREE DETECTION OF A NEUROTROPHIC FACTOR PROTEIN - CEREBRAL DOPAMINE NEUROTROPHIC FACTOR

Neurotrophic factors (NFs) are family of proteins secreted from neurons and neuron-supporting cell and have been shown to be promising candidates for gene therapy of such major neurodegenerative diseases in human as Alzheimer`s and Parkinson’s^1-3. NFs such as brain-derived neurotrophic factor (BDNF), cerebral dopamine neurotrophic factor (CDNF), and mesencephalic astrocyte derived neurotrophic factor (MANF), were found to affect selectively on development, maintenance and survival of neurons and their abnormal levels in the blood may be associated with a number of neurological and mental disorders and diabetes^4,5. Although NF proteins are still not confirmed as clinically validated biomarkers for diagnostics, the design and development of synthetic receptors for the selective recognition of a specific NF protein could be promising with respect of both fundamental studies of NF proteins interactions and their role in neurodegenerative diseases diagnostics and/or the follow-up of neuroprotective therapies.

In this study we demonstrated the preparation of molecularly imprinted polymer (MIP) for selective recognition of CDNF as a model NF protein. The synthesis method exploiting the surface imprinting approach allowed the reliable interfacing of CDNF-selective MIP film (CDFN-MIP) with a surface acoustic wave (SAW) biosensing platform. The resulted CDNF-MIP sensor was capable of detecting CDNF with dissociation constants in the submicromolar range (68 nM). The competitive assays performed in the presence of similar size protein demonstrated the preferential binding of the template protein, CDNF, to the CDNF-MIP, as compared to the non-template protein, MANF, that is homologous to CDNF (amino acid identity-59%)².

Acknowledgments
This work was supported by Tallinn University of Technology in the frame of the Development project (grant SS425).

References

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