Development of a Peptide-Based Biosensor System for the Detection of Prostate Cancer Cells
Project no. 23143 · Status: Kapanmış · 2021
Summary
<p>Cancer is a complex disease that dates back to ancient times and has not been developed an exact remedy to cure and threat the human life owing to occurs in anomaly while cell dividing process. Treatment of the disease is possible with early diagnosis. For this reason, studies for the diagnosis and treatment of cancer have been attracting attention since the last century. Liquid biopsy techniques, which have been used for diagnostic purposes in recent years, require complex and expensive devices, even though they are an effective method. In this thesis, it is aimed to develop a biosensor which capable of directly detecting prostate cancer cells suitable for liquid biopsy. For this purpose, screen printed gold electrodes are modified with cysteamine, PAMAM, avidine and biotinylated AMP Citropin A. In addition to being considered and developed as an alternative to antibiotics in recent years, AMP’s also show cytotoxic effects for many types of cancer. In this study, besides the cytotoxic properties of AMPs, it was aimed to use Citropin A as a biorecognition agent by taking advantage of its high affinity for prostate cancer cells. Thus, AMP, which is immobilized on the surface, will bind to prostate cancer cells in the sample and cause a change in resistance. The resistance changes that occurred were determined with the help of electrochemical impedance spectroscopy (EIS) during the study, and confirmed by cyclic voltammetry (CV). It has been observed that the biosensor developed according to chronoimpedimetric analyzes can detect LNCaP cells in as little as 300 seconds and DU-145 and PC-3 cells in a reasonable time of 600 seconds. Linear detection limits were established in the concentration range of 1500 – 12000 cells/L, the lowest limit of detection (LOD) was 518 cells/L; the lowest limit of detection (LOQ) value was calculated as 1570 cells/L. The reproducibility, reproducibility and selectivity tests were carried out in cell solutions created by adding standard into the serum sample. As a result, the developed biosensor can detect cancerous prostate cells in low concentration with good selectivity, high sensitivity, very low detection limit and a great economic advantage.</p>