Design of molecular wires based on supramolecular structures for application in glucose biosensors.
In the present work, the synthesis and the spectroelectrochemical characterization of a novel iron compound derived of tetra-2-pyridyl-1,4-pyrazine (TPPZ) with hexacyanoferrate species forming a very stable supramolecular complex in the presence of polypyrrole (PPY) matrix, is described. The hybrid material has shown excellent catalytic activity towards H(2)O(2) detection that makes it suitable for being used as redox mediator in a glucose biosensor. The hybrid FeTPPZFeCN/PPY film presents satisfactory detection limits and high sensitivity for H(2)O(2) in the presence of K(+) or Na(+) ions. For the glucose biosensor, a linear range up to 1.1 mmoll(-1) of glucose was observed with no interferences. In this case, the sensitivities obtained were 7.88 and 5.90 microAmmol(-1)lcm(-2) in phosphate buffer or NaCl solutions, respectively. The good sensitivity is related to the presence of a high-dimensional structure based on polypyridine type ligands providing an "electron antennae effect" facilitating electron tunneling between the protein and the electrode.
Instituto de Química, Universidade de São Paulo, C.P. 26077, São Paulo 05513-970, SP, Brazil.
Wendel A
WA
Alves
Pablo A
PA
Fiorito
Susana I
SI
Córdoba de Torresi
Roberto M
RM
Torresi
D015374:Biosensing Techniques / Q000295:instrumentation*; D005290:Ferric Compounds / Q000737:chemistry; D005295:Ferrocyanides; D005947:Glucose / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000032:analysis; D011108:Polymers; D011719:Pyrazines; D011758:Pyrroles
D005290:Ferric Compounds; D005295:Ferrocyanides; D011108:Polymers; D011719:Pyrazines; D011758:Pyrroles; C116383:ferrocyn; C067635:polypyrrole; D006861:Hydrogen Peroxide; D005947:Glucose