Nano-moles detection of tumor specific biomarker DNA for colorectal cancer detection using vertically aligned multi-wall carbon nanotubes based flexible electrodes.

• Vertically-aligned carbon nanotubes were synthesized using chemical vapor deposition. • Nanotubes patterns were transferred on flexible substrate by hot compress method. • Carcinoembryonic antigen-related cell adhesion molecule5 was utilized as biomarker. • Fabricated sensor detected colorectal cancer with lower detection limit of 0.92 μM. A genosensor, flexible and low cost as well, has been fabricated to efficiently detect colorectal cancer cell by targeting CEACAM5, a tumor biomarker. Sensing electrode was fabricated with efficient transfer of a pattern of vertically aligned multi-wall carbon nanotubes on flexible polyethylene terephthalate (PET) substrate by hot press technique, a technologically advanced one. The purpose was to make the sensor device stretchable, bendable, transparent, disposable and heat resistant; without losing the pristine character of the electrode material before and after transfer process. Fabricated sensor was characterized by cyclic voltammetry (CV) and electrochemical impedance spectra (EIS). The sensor response was checked by adding target DNA within a range of 50–250 μM and sensor showed a detection limit of 0.92μM; exhibited good linearity with a regression coefficient of 0.96 obtained through calibration plot. The sensor was found to be highly sensitive, stable and good specificity as binding occurs only with the complementary DNA. Besides, the genosensor showed relative standard deviation of 6.5 % and 6.7 % at respective 100 μM and 150 μM complementary DNA concentrations. Reproducibility and stability are two crucial parameters where the developed sensor have scored extremely well. [ABSTRACT FROM AUTHOR]