Development of liquid crystal biosensor for the detection of amyloid beta-42 levels associated with Alzheimer's disease.


Kemiklioglu E., Tuncgovde E. B. , Ozsarlak-Sozer G.

Journal of bioscience and bioengineering, vol.132, pp.88-94, 2021 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 132
  • Publication Date: 2021
  • Doi Number: 10.1016/j.jbiosc.2021.03.016
  • Title of Journal : Journal of bioscience and bioengineering
  • Page Numbers: pp.88-94
  • Keywords: Liquid crystal, DMOAP coating, Liquid crystal biosensor, Amyloid beta-42, Apolipoprotein E4, APOLIPOPROTEIN-E, PROTEIN, PEPTIDES, AMPLIFICATION, AGGREGATION, DIAGNOSIS, BIOMARKER, SURFACES

Abstract

This study represents the development of a biosensor which is based on the liquid crystal (LC) orientation as a function of the peptide concentration to detect an amyloid-beta-42 (A beta 42) antibody-antigen binding events. The A beta 42 peptide binds to the A beta 42 antibody forming an immunocomplex which is immobilized on the Dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride (DMOAP) coated surface. The disturbed orientation of LCs as a result of the binding of the formed immunocomplex was observed using the polarized optical microscope (POM) as a function of decreasing A beta 42 peptide concentration from 1000 to 1 pg/ml. The concentration, as low as 1 pg/ml of A beta 42 peptide was able to be successfully detected in our system. Apolipoprotein E4 (ApoE4), that specifically bound to the A beta 42 peptide, was added into the system and a remarkable change in reflection spectra of samples was observed with increasing A beta 42 peptide concentration. The concentration of ApoE4 protein was detected in the range of 0.1-30 nM by this system due to the interaction between the two proteins. (C) 2021, The Society for Biotechnology, Japan. All rights reserved.