Electrochemical RNase A Detection Using an Electrode with Immobilized Ferrocenyl Deoxyribooligonucleotide Containing Cytidine Residue

Abstract

A ferrocenyl deoxyribooligonucleotide (FcODN(rC)) with contiguous cytosine bases and a single ribonucleotide, cytidine, was immobilized on a gold electrode, and this electrode was used to detect RNase A. RNase A activity in a solution was assessed using cyclic voltammetry, and it was found that the current response of the sensor electrode decreased with increasing enzyme concentration. An extremely low detection limit of 1.0 10 À11 g mL À1 RNase A was observed, with 15-90 % changes in the current signal. RNase activity can be an indicator of a number of diseases; therefore, this probe has great potential for applications in medical diagnostics.

Highly Sensitive Nuclease Assays Based on Chemically Modified DNA or RNA

“…RNase A activity is represented by the decreasing current with a linear range of 0.2–10 ng/mL and a detection limit of 0.2 pg. RNase A detection was performed by electrode-immobilized FcODN containing dArCdAdA and continuous cytosines (Cs) ( Figure 8b ) [ 32 ]. This FcODN was immobilized on the electrode through reaction of its continuous Cs with activated ester moieties coating the electrode surface.…”

Biorecognition and highly sensitive determination of Ribonuclease A with chemiluminescence sensor based on Fe3O4/multi-walled carbon nanotubes/SiO2-surface molecular imprinting polymer

“…4 The detection of RNase A is highly useful in diagnostic medicine as its level in the blood serum can be used as a diagnostic marker for many diseases, including myocardial infarction and pancreatic cancer. 5,6 Molecular imprinting polymers (MIP) possess high selective recognition and capture capabilities. In 1949, F. H. Dickey 7 pioneered the concept of "specicity adsorption" which was regarded as the seed of molecular imprinting technology.…”

Homogeneous Electrochemiluminescence Biosensor for the Detection of RNase A Activity and Its Inhibitor

“…It is of great significance to develop new approaches for cost-effective detection of RNase A. Ribonucleotide cytosine and uracil (rC and rU) are the enzyme cutting sites for RNase A, − so a chimeric DNA probe that contains rC or rU base can be specifically hydrolyzed into small fragments by RNase A too. According to such a biochemical mechanism, some biosensors based on electrochemical and fluorescent technology were developed. − For example, Takenaka et al designed a rC containing chimeric DNA probe which was immoblized on the gold electrode; the presence of RNase A would hydrolyze the probe and release ferrocenyl-labeled fragment, leading to a decreasing current response for quantification.…”

“…According to such a biochemical mechanism, some biosensors based on electrochemical and fluorescent technology were developed. 13−16 For example, Takenaka et al 14 designed a rC containing chimeric DNA probe which was immoblized on the gold electrode; the presence of RNase A would hydrolyze the probe and release ferrocenyl-labeled fragment, leading to a decreasing current response for quantification.…”