Molecularly imprinted polymer-based SAW sensor for label-free detection of cerebral dopamine neurotrophic factor protein

In this study we report on a surface acoustic wave (SAW) sensor modified with a molecularly imprinted polymer (MIP) film that selectively recognizes the cerebral dopamine neurotrophic factor (CDNF) protein, a potential biomarker for early-stage diagnosis and/or the follow-up of neuroprotective therapies. CDNF-MIP as a synthetic recognition element was prepared by a simple electrochemical surface imprinting approach allowing its reliable interfacing with SAW sensor. The optimal thickness of the MIP layer as well as a suitable pretreatment method were adjusted to improve the recognition capacity and selectivity of the resulting CDNF-MIP sensor. The 4.7 nm thick CDNF-MIP layers treated in 0.04 mg/ml HSA solution demonstrated the highest relative rebinding towards CDNF. The selectivity of the sensor was studied by the carefully designed competitive binding experiments, which revealed that the sensor can sense CDNF confidently in a label-free manner starting from 0.1 pg/ml. We anticipate that the findings can be a premise for fabricating the desired cost-effective research or diagnostics tools in the field of neurodegenerative diseases.