Low potential stable glucose detection at dendrimers modified polyaniline nanotubes

Abstract

The utilization of nanostructured materials for development of biosensors is a growing field in medical diagnostics. In this work a glucose biosensor based on bioactive polyglycerol (PGLD) and chitosan dendrimers (CHD) was developed. PGLD and CHD were bioconjugated with the enzyme glucose oxidase (GOx) to obtain dendrimers with glucose sensing properties. Polyaniline nanotubes (PANINT´s) were used as electron mediator due to their high ability to promote electron-transfer reactions involving GOx. The PGLD-GOx and CHD-GOx were entrapped in PANINT´s during template electrochemical polymerization of aniline. The prepared PGLDGOx/PANINT´s and CHD-GOx/PANINT´s biosensors exhibit a strong and stable amperometric response to glucose even at a low potential of +100 mV. The based PGLD-GOx/PANINT´s and CHD-GOx/PANINT´s biosensors showed a good performance in glucose concentrations range in human blood. A comparison of the sensitivities to glucose showed that both biosensors have a linearity range between 0.02 and 10 mM, though PGLD-GOx/PANINT´s is more sensitive (10.41 vs. 7.04 nA.mM -1 ). The difference in the biosensor behavior and the high sensitivity of the PGLD-GOx/PANINT´s may be due to the specific organization of GOx layer at surface of the modifier macromolecule PGLD and their distribution in PANINT´s. The enzyme affinity for the substrate, K M app remains quite good after GOx immobilization on PGLD and CHD dendrimers and entrapment of the bioconjugates in PANINT´s.

Sulfonated polyaniline: influence of sulfonation routes on its thermal and structural characteristics

“…PAni nanofibers doped with several inorganic/organic acids were synthesized by interfacial polymerization being the morphology, thermal stability and electrical conductivity dependent on the dopant chemical nature 13 . Dendrimers modified polyaniline nanotubes as biosensor for detecting glucose at low voltage was prepared by Queiroz and his group 14 . This research deals with the sulfonation of PAni-EB at different time and temperature conditions.…”

Polyaniline Nanofibers-Embedded Gold Nanoparticles Obtained by Template-Free Procedure with Immobilization Prospects

“…In our case, the diameter of the PANI nanofibers (approximately 100 nm) is lower than that obtained by other syn-thesis methods [46][47][48]. Particularly, for developing sensors and biosensors applications, polyaniline nanostructures with diameters lower than 200 nm are desired, and usually very complex dopants with bulky side groups are needed, such as sulfonated naphthalene derivatives [49], fullerenes [50] or dendrimers [51]. In the case of PT-AuNPs nanocomposites synthesized by the ultrasound-assisted method described in this paper, the diameter of the nanofiber was considerably higher, far from the desired 100 nm or less.…”

Continuous Glucose Monitoring System Based on Percutaneous Microneedle Array

“…Biocompatible insulating varnish reduces electrical conductivity in areas outside the glucose oxidase layer to ensure signal correctness. The GOD layer is to achieve specific detection of glucose [ 21 ]. The Nafion layer can improve adsorption of the object to be detected on the electrode surface and also mitigate interference from acetaminophen and uric acid.…”