O Desafio no Diagnóstico Analítico das Perturbações do Neurodesenvolvimento: Dispositivos Neuroquímicos Inovadores

NeuroDevice intends to fill the existing gap on the ADHD and ASD prognosis and diagnosis by developing the first bioanalytical test able to detect specific miRNA biomarkers associated to these disorders. This bioanalytical test will be based on the design of disposable and innovative multitarget miRNA-based biosensors. The miRNA-based biosensors will be assembled on magnetic beads (MBs) as nanomagnetic surfaces, using ePAD as electrochemical platform and portable and wireless electrochemical potentiostat as analytical device. The simple design, the small dimension, the low power requirement, and the ability to simultaneously, on-site, and real-time (during the medical appointment and at early stage of the disease ́s) detect up to 28 miRNAs are added advantages. NeuroDevice proposal intends to: i) Design and develop ePAD nanostructures incorporating graphene; The use of ePAD as a transducer will allow the production of low-cost electrochemical paper-based analytical devices (ePAD) able to connect commercial portable and wireless smartphone electrochemical potentiostat. The incorporation of nanomaterials, graphene, onto ePAD will improve the sensitivity of this innovative electrochemical device. ii) Develop electrochemical multitarget miRNA-based biosensor platform; The multitarget electrochemical miRNA-based biosensors approach involves the formation of DNA/miRNA heterohybrids by direct hybridization assembled onto the MBs. To meet the challenges of sensitivity, the electrochemical signal amplification will be carried out with multienzyme able to perform and to recognize anti-DNA-RNA hybrid antibodies. iii) Clinical study The miRNA-based biosensor for NDDs diagnosis will be tested in a population with clinically diagnosed with ADHD or ASD. Thus, a clinical hospital-based study will be designed, being recruited individuals with different ND diagnosis, namely: Cohort 1, patients with ADHD diagnosis; Cohort 2, patients with ASD diagnosis; and Cohort 3 composed by heathy individuals. From the individuals’ enrolled in the study, it will be collected a blood and saliva sample that will be used in the miRNA-based biosensor and in the RTqPCR. This procedure will allow the relative quantification of the specific miRNA signatures, in order to validate the results obtained with the biosensor developed. iv) Statistical correlation between salivary and blood miRNA levels The relationship between blood and salivary miRNA expression activity is not well understood. So, statistical analysis (PCA, variance components analysis, hierarchical clustering, and enrichment analysis) will be performed to better understand the relationship between miRNA expression in peripheral blood and saliva. The statistical finding will confirm if saliva can be introduced as credible, non-invasive and diagnostic biofluids for the miRNAs extraction. v) Validation of the developed multitarget electrochemical miRNA-based biosensor The miRNA-based biosensor will be validated using the miRNA relative quantification by RTqPCR. Thus, we will be able to compare results between the techniques and evaluate the performance of the device under-development. This approach will be used all time during the development of the device to optimize all the conditions. vi) Turning academic research into a commercial product Find commercial partners to convert the academic analytical test in a commercial product and use this test to help clinicians to perform improved NDDs.