A Layer‐by‐Layer Biosensing Architecture Based on Polyamidoamine Dendrimer and Carboxymethylcellulose‐Modified Graphene Oxide

Abstract

A novel nanostructured architecture for the construction of electrochemical enzyme biosensors is here described. It implies the electrostatic layer‐by‐layer assembly of four‐generation ethylenediamine core polyamidoamine G‐4 dendrimers on glassy carbon electrodes coated with a graphene oxide‐carboxymethylcellulose hybrid nanomaterial. This modified surface was further employed for the covalent immobilization of the model enzyme tyrosinase through a glutaraldehyde‐mediated cross‐linking. The prepared enzyme electrode allowed the amperometric detection of catechol in the 2–400 nM range. The biosensor showed excellent analytical performance with high sensitivity of 6.3 A/M and low detection limit of 0.9 nM. The enzyme electrode retained over 93 % of the initial activity after 40 days at 4 °C.

Graphene/Poly(vinylferrocene) Composite Based Amperometric Biosensor for L‐lysine Determination

“…The amperometric response of the biosensor varied linearly in the range from 9.9×10 −7 to 3.1×10 −4 M (inset in Figure B) with a low detection limit of 2.3×10 −7 M. LOD was determined using the equation LOD=3 S b /m . In this equation m refers to the slope of the calibration graph and S b refers to the standard deviation of 10 different amperometric signals recorded for the lowest L‐lysine concentration (1 μM) in the calibration graph . The detection limit of LyOx/PVF/GR/GCE is lower than that of lysine oxidase/Au nanoparticles/multiwalled carbon nanotubes /polyaniline modified gold electrode (5.0×10 −6 M) , overoxidized polypyrrole film and lysine oxidase modified platinum electrode (4.0×10 −6 M) and glutaraldehyde, bovine serum and lysine oxidase modified platinum electrode (1.0×10 −6 M) .…”

Recent Developments of Carboxymethyl Cellulose

“…In the following year, Borisova et al (2016) [ 319 ] developed a layer-by-layer biosensor of reduced graphene oxide/CMC/platinum nanoparticles (decorated with polyamidoamine G-4 dendrimers and modified magnetic nanoparticles) for the detection of xanthine in fish samples ( Figure 7 a). In another research work, the same research group fabricated a nanostructured electrochemical biosensor using polyamidoamine G-4 and CMC-modified graphene oxide ( Figure 7 d) [ 320 ]. This time, the biosensor exhibited a susceptible analytical performance (i.e., 6.3 A/M), even at a low detection limit (0.9 nM).…”

Design of a reduced-graphene-oxide composite electrode from an electropolymerizable graphene aqueous dispersion using a cyclodextrin-pyrrole monomer. Application to dopamine biosensing

“…It is noteworthy that the addition of ascorbic acid, uric acid and glucose as interferents did not result in any significant current change for all types of electrodes (figure S1). The comparison with other tyrosinase-based biosensors involving graphene (table S1), clearly indicates that our configuration leads for the detection of catechol and dopamine to almost the best performance in terms of linear range and detection limit [23][24][25][26][27][28][29][30][31][32].…”