Rapid
and accurate diagnostic technologies for early-state identification
of cardiovascular abnormalities have become of high importance to
prevent and attenuate their progression. The capability of biosensors
to determine an increase in the concentration of cardiovascular protein
biomarkers in circulating blood immediately after a myocardial infarction
makes them ideal point-of-care platforms and alternative approaches
to electrocardiograms, chest X-rays, and different laboratory-based
immunoassays. We report here a generic approach toward multianalyte
sensing platforms for cardiac biomarkers by developing aptamer-based
electrochemical sensors for brain natriuretic peptide (BNP-32) and
cardiac troponin I (cTnI). For this, commercial gold-based screen-printed
electrodes were modified electrophoretically with polyethyleneimine/reduced
graphene oxide films. Covalent grafting of propargylacetic acid integrates
propargyl groups onto the electrode to which azide-terminated aptamers
can be immobilized using Cu(I)-based “click” chemistry.
To ensure low biofouling and high specificity, cardiac sensors were
modified with pyrene anchors carrying poly(ethylene glycol) units.
In the case of BNP-32, the sensor developed has a linear response
from 1 pg mL–1 to 1 μg mL–1 in serum; for cTnI, linearity is observed from 1 pg mL–1 to 10 ng mL–1 as demanded for early-stage diagnosis
of heart failure. These electrochemical aptasensors represent a step
further toward multianalyte sensing of cardiac biomarkers.
We report the use of Co-porphyrins as electrochemical tags for a highly sensitive and selective genosensor. An avian influenza virus-based DNA sequence characteristic of H5N1 was detected at femtomolar levels from competing non-complementary sequences through hybridisation with the labeled DNA.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.