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.