A Novel Ormosil Based Electrocatalytic Biosensor for Glucose/Ethanol Based on Dehydrogenase Modified Electrode

Abstract

A novel ormosil material for designing electrocatalytic biosensors for glucose and ethanol based on dehydrogenase catalyzed reactions is reported. The electrode material is prepared using palladium‐linked glycidoxypropyltrimethoxysilane, ferrocene monocarboxylic acid, trimethoxysilane and HCl. The ormosil prepared from these ingredients shows reversible electrochemistry of ormosil encapsulated ferrocene. The electrocatalytic oxidation of NADPH/NADH and subsequently novel dehydrogenase based biosensors for glucose and ethanol are developed. The results based on cyclic voltammetry and amperometry are reported. The enzyme sensors are developed based on the modification of electrode material by dehydrogenase enzymes. The modification of electrode material is made by two approaches of enzyme immobilization: immobilization of dehydrogenase within polyvinyl alcohol and sandwiching the dehydrogenase within two layers of ormosils among which the first layer being the electrode material itself and the second layer of ormosil prepared without palladium linkage precursor and ferrocene. The biosensor made by the second approach shows high stability and much better reproducibility of enzyme electrode performance. The results on glucose and alcohol sensing based on electrochemical measurements are reported.

Organically Modified Silica Nanoparticles Interaction with Macrophage Cells: Assessment of Cell Viability on the Basis of Physicochemical Properties

“…This suggests that encapsulation of metallic core in polymeric structure not only makes formulation biocompatible, but also resulted in stable multifunctional advanced system . Apart from being utilized as coating, “ORMOSIL” nanoparticles have also been synthesized with diverse surface properties for different biomedical applications such as the delivery of DNA, biosensing for glucose or ethanol, biomedical imaging, gene delivery, and live cell imaging, as drug delivery systems and in photodynamic therapy . When functionalized with Near‐Infrared fluorophore and radiolabeled iodine‐124 act as probe for safe in vivo bio‐imaging, and tagged with antibodies such as antimesothelin and anticlaudin‐4 can target pancreatic cancer cells .…”

Chiral Electrochemical Recognition by Very Thin Molecularly Imprinted Sol−Gel Films

“…In addition, the ease of SG fabrication, mild reaction conditions, commercial availability of a wide variety of functional monomers, physical rigidity of the matrix, chemical inertness, and resistance to thermal and solvent stresses have all made the SG methodology attractive for molecular imprinting of thin films [11][12][13][14][15] and a perfect platform for designing various electrochemical applications. [16][17][18][19] Thus, SG-modified electrodes 20,21 have found many applications, forexample,inelectrocatalysis, [22][23][24][25] enzymaticcatalysis, [26][27][28] sensors and biosensors, 5,[29][30][31][32] electorchemiluminescence, 33,34 10.1021/la050240y CCC: $30. 25 batteries and fuel cells, [35][36][37] and electroactive films.…”

“…Sol−gel (SG) materials inherently combine these two requirements, namely, the ability to form very thin films and matrix porosity. In addition, the ease of SG fabrication, mild reaction conditions, commercial availability of a wide variety of functional monomers, physical rigidity of the matrix, chemical inertness, and resistance to thermal and solvent stresses have all made the SG methodology attractive for molecular imprinting of thin films − and a perfect platform for designing various electrochemical applications. − Thus, SG-modified electrodes , have found many applications, for example, in electrocatalysis, − enzymatic catalysis, − sensors and biosensors, ,− electorchemiluminescence, , batteries and fuel cells, − and electroactive films. ,, The combination of thin films of imprinted polymers as the sensing element and electrodes as the transduction element was investigated by us and other groups. ,− …”

Modification of Galactitol Dehydrogenase from Rhodobacter sphaeroides D for Immobilization on Polycrystalline Gold Surfaces

“…to functionalized self-assembling monolayers (SAM) [30][31][32][33][34][35] applied onto the metal surface, or in the case of gold surfaces, enzymes are bound via thiol linkages. If preparative conversions with dehydrogenases are envisaged, the cofactor is needed, and a mediator [36][37][38][39][40] for minimizing the overpotential of the electrochemical NADH oxidation which ranges between 1.0 V and 1.2 V vs NHE. [41][42][43] A prerequisite for immobilizing enzymes onto gold surfaces is exposed cysteine residues that form the linkages.…”

“…In many applications, enzymes are bound to functionalized self-assembling monolayers (SAM) − applied onto the metal surface, or in the case of gold surfaces, enzymes are bound via thiol linkages. If preparative conversions with dehydrogenases are envisaged, the cofactor is needed, and a mediator − for minimizing the overpotential of the electrochemical NADH oxidation which ranges between 1.0 V and 1.2 V vs NHE. − A prerequisite for immobilizing enzymes onto gold surfaces is exposed cysteine residues that form the linkages. However, if the molecular structure of a given enzyme is unknown, an empirical approach has to evaluate if and to what extent binding of the enzyme on the metal surface will retain its activity.…”