Aldehyde functionalized ionic liquid on electrochemically reduced graphene oxide as a versatile platform for covalent immobilization of biomolecules and biosensing.

An aldehyde functionalized ionic liquid, (3-(3-formyl-4-hydroxybenzyl)-3-methylimidazolium hexafluorophosphate) (CHO-IL) has been employed herein as a multiple host platform for the covalent immobilization of mediator as well as enzyme. The CHO-IL was immobilized on electrochemically reduced graphene oxide (ERGO) through the π-π stacking of hydroxybenzyl and imidazolium groups with ERGO and subjected to further covalent attachment of Azure A (Azu-A) mediator or glucose oxidase (GOx) enzyme. Electroactive, water soluble organic dye Azu-A was effectively immobilized to the host IL through simple Schiff base reaction. Azu-A was rendered leak-free in the electrode setup and also responded well for the amperometric determination of H2O2 over a linear range of 0.03-1mM with a detection limit and sensitivity of 11.5µM and 133.2µAmM-1cm-2, respectively. Further, attempts were made to explore the CHO-IL platform for the covalent immobilization of GOx enzyme which served well in retaining the enzyme nativity, reactivity and stability. Under optimized conditions, mediatorless GOx biosensor developed based on direct electrochemistry has exhibited an impressive analytical signal towards glucose detection in the linear range of 0.05-2.4mM with a detection limit and sensitivity of 17µM and 17.7µAmM-1cm-2, respectively. The reliability of the proposed Azu-A based chemical sensor and GOx based biosensor towards the determination of H2O2 and glucose in the real samples have been demonstrated. The remarkable analytical parameters and long term stability of both the sensors could be envisioned as a result of facile immobilization platform and immobilization strategy.

[1]  Anthony P F Turner,et al.  Biosensors: sense and sensibility. , 2013, Chemical Society reviews.

[2]  E. Farjami,et al.  Electrodeposited Silver Nanoparticles on Carbon Ionic Liquid Electrode for Electrocatalytic Sensing of Hydrogen Peroxide , 2009 .

[3]  T. Heinze,et al.  Advanced Cellulose Fibers for Efficient Immobilization of Enzymes. , 2016, Biomacromolecules.

[4]  K. Thenmozhi,et al.  Horseradish peroxidase and toluidine blue covalently immobilized leak-free sol-gel composite biosensor for hydrogen peroxide. , 2017, Materials science & engineering. C, Materials for biological applications.

[5]  F. Gao,et al.  Mediatorless glucose biosensor and direct electron transfer type glucose/air biofuel cell enabled with carbon nanodots. , 2015, Analytical chemistry.

[6]  Xiaobo Zou,et al.  A real-time-range potentiostat coupled to nano-Au-modified microband electrode array for high-speed stripping determination of human blood lead. , 2017, Biosensors & bioelectronics.

[7]  R. Giernoth.  Task-specific ionic liquids. , 2010, Angewandte Chemie.

[8]  C. Brett,et al.  Electrochemical impedance studies of chitosan-modified electrodes for application in electrochemical sensors and biosensors , 2010 .

[9]  Veerappan Mani,et al.  Direct electrochemistry of glucose oxidase at electrochemically reduced graphene oxide-multiwalled carbon nanotubes hybrid material modified electrode for glucose biosensor. , 2013, Biosensors & bioelectronics.

[10]  B. D. Malhotra,et al.  Highly sensitive porous carbon and metal/carbon conducting nanofiber based enzymatic biosensors for triglyceride detection , 2017 .

[11]  M. Asadi,et al.  Synthesis, characterization, DNA binding, cleavage activity, cytotoxicity and molecular docking of new nano water-soluble [M(5-CH₂PPh₃-3,4-salpyr)](ClO₄)₂ (M = Ni, Zn) complexes. , 2016, Dalton transactions.

[12]  T. Hayat,et al.  Macroscopic, Spectroscopic, and Theoretical Investigation for the Interaction of Phenol and Naphthol on Reduced Graphene Oxide. , 2017, Environmental science & technology.

[13]  Audrey Sassolas,et al.  Immobilization strategies to develop enzymatic biosensors. , 2012, Biotechnology advances.

[14]  Ping Wang,et al.  An ultrasensitive sandwich-type electrochemical immunosensor based on the signal amplification strategy of echinoidea-shaped Au@Ag-Cu2O nanoparticles for prostate specific antigen detection. , 2018, Biosensors & bioelectronics.

[15]  Hui Guohua,et al.  D-glucose, D-galactose, and D-lactose non-enzyme quantitative and qualitative analysis method based on Cu foam electrode. , 2015, Food chemistry.

[16]  Tsukasa Torimoto,et al.  New Frontiers in Materials Science Opened by Ionic Liquids , 2010, Advanced materials.

[17]  Q. Zhang,et al.  Direct electrochemistry and electrocatalysis of myoglobin covalently immobilized in mesopores cellular foams. , 2010, Biosensors & bioelectronics.

[18]  C. Brett,et al.  Application of functionalised carbon nanotubes immobilised into chitosan films in amperometric enzyme biosensors , 2009 .

[19]  Ziming He,et al.  A new strategy for achieving vertically-erected and hierarchical TiO2 nanosheets array/carbon cloth as a binder-free electrode for protein impregnation, direct electrochemistry and mediator-free glucose sensing. , 2016, Biosensors & bioelectronics.

[20]  L. Capitán-Vallvey,et al.  Electrochemiluminescent disposable cholesterol biosensor based on avidin-biotin assembling with the electroformed luminescent conducting polymer poly(luminol-biotinylated pyrrole). , 2012, Analytica chimica acta.

[21]  C. Ravikumar,et al.  Azure A chloride: computational and spectroscopic study , 2009 .

[22]  S. Sriman Narayanan,et al.  Electrochemical behavior of Azure A/gold nanoclusters modified electrode and its application as non-enzymatic hydrogen peroxide sensor. , 2012, Colloids and surfaces. B, Biointerfaces.

[23]  L. Qu,et al.  Direct electrochemistry and electrocatalysis of glucose oxidase on three-dimensional interpenetrating, porous graphene modified electrode , 2013 .

[24]  J. Kaar,et al.  Elucidating sequence and solvent specific design targets to protect and stabilize enzymes for biocatalysis in ionic liquids. , 2017, Physical chemistry chemical physics : PCCP.

[25]  Dal‐Hee Min,et al.  Emerging Approaches for Graphene Oxide Biosensor. , 2017, Analytical chemistry.

[26]  S. Deng,et al.  A non-enzyme electrochemical qualitative and quantitative analyzing method for glucose, D-fructose, and sucrose utilizing Cu foam material , 2015 .

[27]  Guohua Hui,et al.  Sucrose quantitative and qualitative analysis from tastant mixtures based on Cu foam electrode and stochastic resonance. , 2016, Food chemistry.

[28]  Po-Yu Chen,et al.  Electrochemical study of a new non-heme iron complex-modified carbon ionic liquid electrode with electrocatalytic activity towards hydrogen peroxide reduction , 2015 .

[29]  Lu Hongyang,et al.  Study of small-cell lung cancer cell-based sensor and its applications in chemotherapy effects rapid evaluation for anticancer drugs. , 2017, Biosensors & bioelectronics.

[30]  Joseph Wang.  Electrochemical glucose biosensors. , 2008, Chemical reviews.

[31]  Longwei Yin,et al.  Amperometric hydrogen peroxide and glucose biosensor based on NiFe2/ordered mesoporous carbon nanocomposites. , 2015, The Analyst.

[32]  C. Lagrost,et al.  Electrochemical reactivity in room-temperature ionic liquids. , 2008, Chemical reviews.

[33]  Yan-Feng Bai,et al.  Direct electron transfer of glucose oxidase-boron doped diamond interface: a new solution for a classical problem. , 2014, Analytical chemistry.

[34]  Yasuhiko Ito,et al.  Room temperature ionic liquids of alkylimidazolium cations and fluoroanions , 2000 .

[35]  Qinglin Sheng,et al.  Direct electrochemistry of myoglobin based on electrodeposition of Pd nanoparticles with carbon ionic liquid electrode as basic electrode , 2011 .

[36]  A. Turner,et al.  Hierachically Structured Hollow Silica Spheres for High Efficiency Immobilization of Enzymes , 2013 .

[37]  Emilia Witkowska Nery,et al.  Electrochemical Glucose Sensing: Is There Still Room for Improvement? , 2016, Analytical chemistry.

[38]  A. Walcarius,et al.  Mesoporous Materials‐Based Electrochemical Enzymatic Biosensors , 2015 .

[39]  Jun Liu,et al.  Glucose oxidase-graphene-chitosan modified electrode for direct electrochemistry and glucose sensing. , 2009, Biosensors & bioelectronics.

[40]  D. Saravanakumar,et al.  A bioinspired ionic liquid tagged cobalt-salophen complex for nonenzymatic detection of glucose. , 2017, Biosensors & bioelectronics.

[41]  Liang Li,et al.  Yeast surface displaying glucose oxidase as whole-cell biocatalyst: construction, characterization, and its electrochemical glucose sensing application. , 2013, Analytical chemistry.

[42]  Wei Sun,et al.  Direct electrochemistry and electrocatalysis of hemoglobin in graphene oxide and ionic liquid composite film. , 2014, Materials science & engineering. C, Materials for biological applications.

[43]  M. Khosravi,et al.  Fabrication of gallium hexacyanoferrate modified carbon ionic liquid paste electrode for sensitive determination of hydrogen peroxide and glucose. , 2014, Materials science & engineering. C, Materials for biological applications.

[44]  L. Kubota,et al.  Multifunctional catalytic platform for peroxidase mimicking, enzyme immobilization and biosensing. , 2016, Biosensors & bioelectronics.

[45]  Shen-ming Chen,et al.  A simple electrochemical approach to fabricate a glucose biosensor based on graphene-glucose oxidase biocomposite. , 2013, Biosensors & bioelectronics.

[46]  A. Bard,et al.  Novel Electrochemical Studies of Ionic Liquids , 2002 .