Electrochemical sensor for the detection of multiple reactive oxygen and nitrogen species from ageing central nervous system homogenates

Abstract

Reactive oxygen and nitrogen species (ROS/RNS) have been widely implicated in the ageingThe free radical theory of ageing is one of the most prominent theories to explain the ageing process (Harman, 1956). This theory postulates that ageing and age-related diseases arise as a result of cumulative changes and/or damage to cells and tissues inflicted by reactive species. Under normal physiological conditions, redox homeostasis establishes a dynamic balance between pro-oxidants and antioxidants whereby the production of reactive species are scavenged by antioxidants to minimise damage. However, with increasing age, studies have shown that the pro-oxidantantioxidant balance is compromised with a shift to the former resulting in an increase in reactive species. This imbalance induces oxidative stress, a state where endogenous antioxidant defense systems are overwhelmed leading to oxidative damage. More recent advances of this theory have shown that while, in laboratory reared animals, oxidative damage does not appear to affect lifespan it certainly increases oxidative damage and can contribute to age-related pathology (Salmon et

Autonomic Receptor‐mediated Regulation of Production and Release of Nitric Oxide in Normal and Malignant Human Urothelial Cells

“…Composite MWCNT microelectrodes (for details, see Fagan‐Murphy et al . ) were used for the detection of nitrite. Initially, the oxidation peak potential for nitrite was obtained using differential pulse voltammetry.…”

Recent Advances in Biosensing for Neurotransmitters and Disease Biomarkers using Microelectrodes

“…Similar to the work of Dias et al . on nitrogen/oxygen species, Fagan‐Murphy et al . have very recently fabricated and applied a simple electrochemical sensor capable of simultaneously monitoring the production of hydrogen peroxide (H 2 O 2 ) and the reactive nitrogen species, peroxynitrite (ONOO − ), •NO and nitrite (NO 2 − ) from ageing central nervous system homogenates .…”

“…The study found direct measurement of * NO concentration dynamics revealed a significant increase in the receptor peak in the triple transgenic mouse model at an early age, indicative of potential for extension into greater detailed studies. [48] Similar to the work of Dias et al on nitrogen/oxygen species, Fagan-Murphy et al [49] have very recently fabricated and applied a simple electrochemical sensor capable of simultaneously monitoring the production of hydrogen peroxide (H 2 O 2 ) and the reactive nitrogen species, peroxynitrite (ONOO À ), * NO and nitrite (NO 2 À ) from ageing central nervous system homogenates. [49] These electrodes were prepared by sealing individual carbon fibers (10 mm diameter) into pulledglass capillaries and the protruding carbon fibers were insulated by electrochemical deposition of poly(oxyphenylene), followed by dendritic platinum black.…”

“…[48] Similar to the work of Dias et al on nitrogen/oxygen species, Fagan-Murphy et al [49] have very recently fabricated and applied a simple electrochemical sensor capable of simultaneously monitoring the production of hydrogen peroxide (H 2 O 2 ) and the reactive nitrogen species, peroxynitrite (ONOO À ), * NO and nitrite (NO 2 À ) from ageing central nervous system homogenates. [49] These electrodes were prepared by sealing individual carbon fibers (10 mm diameter) into pulledglass capillaries and the protruding carbon fibers were insulated by electrochemical deposition of poly(oxyphenylene), followed by dendritic platinum black. [50] The conductive composite material used to modify the electrodes was prepared by mixing multiwall-carbon nanotubes with epoxy resin.…”

Neuroprotective effects of Camellia nitidissima Chi leaf extract in hydrogen peroxide‐treated human neuroblastoma cells and its molecule mechanisms

“…Excessive oxidative stress is considered to be a key player in age‐related brain pathology. The break of equilibrium between reactive oxygen species (ROS) and endogenous antioxidant defenses in brain has been reported to induce dystrophy and death of neurons, ultimately leading to the degeneration of brain function (Fagan‐Murphy, Hachoumi, Yeoman, & Patel, 2016; Halliwell, 1992).…”