CONCLUSION
In summary, a LC-based biosensor for the detection of a biomarker of neurodegenerative disease, Aβ42 peptide, has been developed in this study. The optimum antibody concentration to be used for the detection of the Aβ42 peptide was determined at 25 μg∕ml and it was immobilized on the glass with DMOAP alignment layer. Subsequently, optimum antibody concentration was interacted with various Aβ42 peptide concentrations between 1000 pg/ml and 1 pg/ml. The changes in the orientation of LC direction induced by the antigen-antibody binding events was observed via a POM. Optical measurements of these LC samples were performed by using Ocean Optics spectrometer. According to all these results, the lowest detectable Aβ42 peptide concentration was determined as 1 pg/ml. The optical results showed that there was a 50% reduction in the reflection samples with the decreasing Aβ42 peptide concentration from 1000 pg/ml to 1 pg/ml. The decrement in the Aβ42 peptide leads a less immunocomplex formation. As a result of the studies, an optical biosensor with high sensitivity and selectivity has been developed.