DsDNA-encased single walled carbon nanotubes (SWNTs) biosensor for detecting hydrogen peroxide in biological environment

Abstract

Hydrogen peroxide is a ubiquitous molecule. We exhale it, and take it in from our diet, and excrete it. It plays an important role in physiological and pathological processes. H₂O₂ is closely related to several human diseases including cancers. Single-walled carbon nanotubes (SWNTs) have drawn great interest in chemical and biological optical sensor applications due to their novel near infrared (NIR) optical properties that are extremely sensitive to the surrounding environment. Herein, DsDNA-encased SWNTs for detecting hydrogen peroxide in a biological environment: dsDNA-SWNTs have been used as a bio-probe sensor for optical detection of H₂O₂ in a blood model matrix (BMM) and serum, It has been found that, 1.7 M thiocyanate ion (SCN^-) and 1 mM nitrite ion ( ) have shown the ability to initiate and accelerate the reaction as well as the restoration of suppressed spectral intensity of SWNT. It has been found that, the detection limits (dl) of H₂O₂ in BMM-1.7 SCN^-, BMM-1 mM nitrite ion, and serum were 5.8, 9.4, and 2.9 µM, respectively and thus have the sensitivity  required to detect physiological and environmental of H₂O₂.