WO2020220106A1 - Modification of the surface of screen-printed electrodes - Google Patents

Modification of the surface of screen-printed electrodes Download PDF

Info

Publication number
WO2020220106A1
WO2020220106A1 PCT/BR2020/050150 BR2020050150W WO2020220106A1 WO 2020220106 A1 WO2020220106 A1 WO 2020220106A1 BR 2020050150 W BR2020050150 W BR 2020050150W WO 2020220106 A1 WO2020220106 A1 WO 2020220106A1
Authority
WO
WIPO (PCT)
Prior art keywords
modification
screen
printed electrodes
surface according
electrode
Prior art date
Application number
PCT/BR2020/050150
Other languages
French (fr)
Portuguese (pt)
Inventor
Luiz Ricardo Goulart Filho
Eliton Souto De MEDEIROS
Ana Flávia Oliveira NOTÓRIO
Fabiane Nunes RIELLO
Kaline Do Nascimento FERREIRA
Maria Júlia Rodrigues Da CUNHA
Original Assignee
Cirino Alberto Goulart Eireli - Epp (Biogenetics)
Universidade Federal de Uberlândia
Universidade Federal Da Paraíba - Ufpb
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cirino Alberto Goulart Eireli - Epp (Biogenetics), Universidade Federal de Uberlândia, Universidade Federal Da Paraíba - Ufpb filed Critical Cirino Alberto Goulart Eireli - Epp (Biogenetics)
Publication of WO2020220106A1 publication Critical patent/WO2020220106A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/28—Electrolytic cell components
    • G01N27/30—Electrodes, e.g. test electrodes; Half-cells
    • G01N27/327—Biochemical electrodes, e.g. electrical or mechanical details for in vitro measurements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/60—Selection of substances as active materials, active masses, active liquids of organic compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to the synthesis, characterization and application of polymeric blends as tools to improve the reading signal, homogenize the surface and facilitate the passage of current in printed electrodes (screen-printed).
  • the invention comprises polymeric structures enriched with different nanomaterials capable of potentiating the electrochemical signal in potentiostat using screen-printed electrodes for diagnosing diseases caused by pathogens and recognized from species-specific ligands.
  • Electrochemistry has as its fundamental objective the study of systems capable of generating useful electrical work from oxirreduction reactions, called galvanic cells, or the reverse process: systems that undergo the oxirreduction process when subjected to electrical work .
  • the electrochemical system is then formed, at least, by two electrodes, or electronic conductors, immersed in an electrolyte that carries the ions.
  • the conduction of electricity being an intrinsic characteristic of the components of this system (TICIANELLI, E. A .; GONZALEZ, E. R. Electrochemistry: Principles and Applications. 2. ed. S ⁇ o Paulo: Edusp, 2005).
  • REPLACEMENT SHEET (RULE 26) previously described. They are: charge transfer (formation of a pair of reactions on the electrodes); ionic conduction (movement of species in the electrolytic solution); displacement of electrode potentials (electrode polarization phenomenon) (TICIANELLi, EA; GONZALEZ, ER Electrochemistry: Principles and Applications. 2. ed. S ⁇ o Paulo: Edusp, 2005).
  • the formation of the double electrical layer is of fundamental importance, since it is formed by the border region between two phases with different compositions leading to the formation of anisotropic forces.
  • the result will be the appearance of a potential difference between the surface and the interior of the solution, which, in this case, can be controlled by an external circuit.
  • This allows to control externally the adsorption of charges and dipoles (TICIANELLI, E. A .; GONZALEZ, E. R. Electrochemistry: Principles and Applications. 2. ed. S ⁇ o Paulo: Edusp, 2005). Together, all of these phenomena will be important for the characterization and functionalization of the electrode surface in a modified electrochemical system.
  • the electrochemistry technique can be considered an object of measurement of species of different natures and associated with a signal transducer system together with processing software allows the creation of (bio) sensors. Able to transform, in this case, currents generated through oxy-reduction reactions into a computational signal that can be interpreted to understand various reactions that take place on the electrode surface (COBBOLD, RSC Transducers for Biomedical Measurements, 1974).
  • IUPAC International Union of Pure and Applied Chemistry
  • biosensors When compared with existing diagnostic techniques for diseases, biosensors have several advantages, including ease of handling, low cost of production, rapid diagnosis, high sensitivity and specificity (SANTANA, LK L, RICARDO, P. C CincinnatiSERUDO, RL, LASMAR, ML, SANTOS, MC; Electrochemical immunosensors and their applications. Scientia Amazónia, Si, v. 6, n. 1, p.31 -41, 2017.
  • the patent BR 102015007505-6 A2 discusses the modification of the electrode surface through the self-assembly technique using magnetic nanoparticles coated with nanoparticles in the construction of diagnostic sensors for schistosomiasis.
  • the patent BR 102012021218-8 A2 uses printed electrodes of modified carbon ink after coming into contact with a solution based on a strong base and crosslinking agent.
  • a polymeric xyloglucan film is used as pre-treatment and stabilization in the construction of a diagnostic sensor for toxic components of Ricina.
  • the patent BR 102016018862-8 A2 brings a different modification, composite electrodes based on graphites and thermoplastic polymers. These electrodes are produced using the dissolution and drying technique and serve to determine organic and inorganic analytes and can be used over a wide pH range and in different electrolytic media.
  • the patent BR 102015028052-1 A2 describes the electrochemical polymerization of poly (3-hydroxyphenolacetic acid) by aqueous dispersion for modification of gold electrodes to form a matrix and hybridization of oligonucleotides in the construction of biosensors.
  • US patent 20130209807 A1 uses modified carbon nanotube sheets for partial or total modification of electrodes that can be applied to sensors, including biosensors.
  • the present invention aims to develop a matrix of polymeric blends enriched with nanomaterials and / or chemical compounds as a tool for modifying the surface of graphite “screen-printed” electrodes.
  • the acquisition of micro and nanofibers that constitute the polymeric matrix was based on the production of solutions of polymeric blends of hydrophobic polymers such as, for example, poly (lactic acid), PLA, and hydrophilic polymers, such as, poly (ethylene glycol), PEG, but not exclusive to these polymers.
  • the solutions can be enriched with other nanomaterials (such as nanotubes and nanoparticles) and these materials may or may not be associated with chemical compounds, both in concentrations varying from 0.5 to 50% of the total polymer mass used (m / m).
  • These solutions will be injected through a system of concentric nozzles, preferably, but not exclusive, at a fixed rate of 10 to 750 uL / min, ideally between 70 and 130 uL / min.
  • the external nozzle will release through a compressed gas system (stored in a cylinder or produced in a compressor) the gas with a pressure of 5 to 100 psi, which is responsible for dragging the enriched polymer solutions (100/0 - 0 / 100% m / v or v / v) transforming them into fibers, ejected towards the collector.
  • a compressed gas system stored in a cylinder or produced in a compressor
  • FTIR analysis allows the determination of the presence of materials and / or chemical compounds, incorporated in the fibers, through their bands or absorbance peaks in the infrared region.
  • Cyclic voltammetry analysis technique in which a potential is applied to the working electrode and the originating electric current is measured. Through this technique it is possible to evaluate the formed oxy-reduction profile. The modification leads to an increase in the measured current reading.
  • Figure 1 shows the micrograph of the micro and nanofibrillar structure of the polymeric matrix in question.
  • Figure 2 shows the graphs of mass loss and derived from the mass losses of the constituent materials and of the polymeric matrix acquired by thermogravimetry, showing the thermal behavior until its degradation.
  • Figure 3 shows the thermal curves obtained by differential scanning calorimetry (DSC), in order to evaluate the processing of the materials produced for the claim in question.
  • DSC differential scanning calorimetry
  • Figure 4 presents the graphs of Fourier Transform Infrared Spectroscopy (FTIR), to which it was possible to identify the absorption frequencies of the functional groups characteristic of the constituent materials and of the polymeric matrices.
  • FTIR Fourier Transform Infrared Spectroscopy
  • Figure 5 shows a schematic of the electrode model used.
  • the diagram illustrates the divisions of the printed electrodes: where 1 is the work area; 2 the counter electrode (both of the same material); 3 represents the silver-coated reference electrode.
  • the diagram illustrates how the polymeric matrix is placed on the electrode, in the work area, for functionalization.
  • Figure 6 illustrates three graphs of the reading in cyclic voltammetry.
  • the readings were made on ten different virgin electrodes, without modification on the surface, and there is no pattern in the curves read.
  • the cyclic voltammetry reading was performed on the same electrodes after the modification and in this case the curves have already demonstrated a standard behavior in all electrodes.
  • the voltammetry technique was used on stabilized electrodes after successive washes.
  • Figure 7 is a Scanning Electron Microscopy image of the work surface of the virgin electrode and the modified electrode.
  • the images (A), (C) and (E) refer to the surface of a virgin electrode in different magnifications.
  • the images are of the surface of an electrode modified in different magnifications.
  • Figure 8 is an image and the respective EDS analysis graph - capable of analyzing the electrode surface components.
  • the image shows the field in which the EDS analysis was performed and in (B) which chemical components were found during the analysis and the respective quantity in proportions for the virgin electrode.
  • (C) and (D) respectively represent the field in which the analysis was performed and the quantification of chemical elements for the modified electrode.
  • Figure 9 represents the graphs of reading by cyclic voltammetry with different scanning speeds to determine the active area of the electrode using the Randles-Sevicik formula.
  • (A) represents the reading graph of different cyclic voltammetry curves with increasing scan speed for the virgin electrode, compared with the readings made on two electrodes with different modifications (in C and E).
  • the lines represented in the graphs (B), (D) and (F) refer to the peak currents, obtained from the cyclic voltammetry curves, for each scan speed.
  • FIG 10 are the graphs representing the active areas of the electrodes, before and after modification with the different types of polymeric matrix.
  • the data are in unit of measure with absolute values and in (B) a normalization of the same data was made to percentage taking as reference the virgin electrode.
  • the nomenclatures from El to E-VII, visible in both (A) and (B) refer to different types of material combinations for modifying the electrode surface.
  • Figure 11 represents cyclic voltammetry readings for different phases of changes in the electrode surface, throughout the process.
  • the continuous line represents the virgin electrode, without modification
  • the dotted line represents in (A) the modification with the polymeric matrix and in (B) the sample adsorption after the modification.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Analytical Chemistry (AREA)
  • Pathology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Nanotechnology (AREA)
  • Urology & Nephrology (AREA)
  • Hematology (AREA)
  • Biomedical Technology (AREA)
  • Inorganic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Biotechnology (AREA)
  • Cell Biology (AREA)
  • Composite Materials (AREA)
  • Microbiology (AREA)
  • Manufacturing & Machinery (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

The present invention relates to the synthesis, characterization and application of polymer blends as tools for improving the read signal, homogenizing the surface and facilitating the passage of current in screen-printed electrodes. The invention therefore covers polymer matrices enriched with different nanomaterials. These materials are capable of boosting the electrochemical signal in potentiostats using screen-printed electrodes to diagnose diseases that are caused by pathogens and recognized using species-specific binders.

Description

“MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS IMPRESSOS” “MODIFICATION OF THE SURFACE OF PRINTED ELECTRODES”
Campo da invenção Field of invention
[0001] A presente invenção refere-se à síntese, caracterização e aplicação de blendas poliméricas como ferramentas para melhorar o sinal de leitura, homogeneizar a superfície e facilitar a passagem de corrente em eletrodos impressos ( screen-printed ). Sendo assim, a invenção compreende estruturas poliméricas enriquecidas com nanomateriais diferentes capazes de potencializar o sinal eletroquímico em potenciostato utilizando eletrodos screen-printed para diagnóstico de doenças causadas por patógenos e reconhecidas a partir de ligantes espécie-específico. [0001] The present invention relates to the synthesis, characterization and application of polymeric blends as tools to improve the reading signal, homogenize the surface and facilitate the passage of current in printed electrodes (screen-printed). Thus, the invention comprises polymeric structures enriched with different nanomaterials capable of potentiating the electrochemical signal in potentiostat using screen-printed electrodes for diagnosing diseases caused by pathogens and recognized from species-specific ligands.
Estado da técnica State of the art
[0002] A eletroquímica tem como objetivo fundamental o estudo de sistemas capazes de gerar trabalho útil elétrico a partir de reações de oxirredução, as chamadas células galvânicas, ou o processo inverso: sistemas que sofrem o processo de oxirredução ao serem submetidos a um trabalho elétrico. O sistema eletroquímico então é formado, no mínimo, por dois eletrodos, ou condutores eletrónicos, imersos em um eletrólito que transporta os íons. Sendo a condução da eletricidade uma característica intrínseca dos componentes desse sistema (TICIANELLI, E. A.; GONZALEZ, E. R. Eletroquímica: Princípios e Aplicações. 2. ed. São Paulo: Edusp, 2005). [0002] Electrochemistry has as its fundamental objective the study of systems capable of generating useful electrical work from oxirreduction reactions, called galvanic cells, or the reverse process: systems that undergo the oxirreduction process when subjected to electrical work . The electrochemical system is then formed, at least, by two electrodes, or electronic conductors, immersed in an electrolyte that carries the ions. The conduction of electricity being an intrinsic characteristic of the components of this system (TICIANELLI, E. A .; GONZALEZ, E. R. Electrochemistry: Principles and Applications. 2. ed. São Paulo: Edusp, 2005).
[0003] A passagem de corrente elétrica através de um sistema eletroquímico gera uma série de reações que podem levar a um desequilíbrio do sistema. Tal desequilíbrio pode ser resumido em três eventos principais que acabam por virar objetos de estudo quando se trata da interface eletrodo/solução naquele sistema [0003] The passage of electric current through an electrochemical system generates a series of reactions that can lead to an imbalance of the system. Such imbalance can be summarized in three main events that end up becoming objects of study when it comes to the electrode / solution interface in that system.
FOLHA DE SUBSTITUIÇÃO (REGRA 26) anteriormente descrito. São eles: transferência de carga (formação de urn par de reações nos eletrodos); condução iônica (movimentação de espécies na solução eletrolítica); deslocamento dos potenciais dos eletrodos (fenômeno de polarização eletródica) (TICIANELLi, E. A.; GONZALEZ, E. R. Eletroquímica: Princípios e Aplicações. 2. ed. São Paulo: Edusp, 2005). REPLACEMENT SHEET (RULE 26) previously described. They are: charge transfer (formation of a pair of reactions on the electrodes); ionic conduction (movement of species in the electrolytic solution); displacement of electrode potentials (electrode polarization phenomenon) (TICIANELLi, EA; GONZALEZ, ER Electrochemistry: Principles and Applications. 2. ed. São Paulo: Edusp, 2005).
[0004] Ainda no conceito de estudo da interface eietrodo/solução a formação da dupla camada elétrica tem fundamental importância, uma vez que esta é formada pela região fronteiriça entre duas fases com composições distintas levando à formação de forças anisotrópicas. No caso de espécies carregadas eletricamente o resultado será o aparecimento de uma diferença de potencial entre a superfície e o interior da solução, que, nesse caso, pode ser controlado por um circuito externo. Isso permite controlar externamente a adsorção de cargas e dipolos (TICIANELLI, E. A.; GONZALEZ, E. R. Eletroquímica: Princípios e Aplicações. 2. ed. São Paulo: Edusp, 2005). Juntos, todos esses fenômenos serão importantes da parte de caracterização e funcionalização da superfície do eletrodo em um sistema eletroquímico modificado. [0004] Still in the concept of studying the electrode / solution interface, the formation of the double electrical layer is of fundamental importance, since it is formed by the border region between two phases with different compositions leading to the formation of anisotropic forces. In the case of electrically charged species, the result will be the appearance of a potential difference between the surface and the interior of the solution, which, in this case, can be controlled by an external circuit. This allows to control externally the adsorption of charges and dipoles (TICIANELLI, E. A .; GONZALEZ, E. R. Electrochemistry: Principles and Applications. 2. ed. São Paulo: Edusp, 2005). Together, all of these phenomena will be important for the characterization and functionalization of the electrode surface in a modified electrochemical system.
[0005] A técnica de eletroquímica pode ser considerada um objeto de medição de espécies de diferentes naturezas e associada a um sistema transdutor de sinal juntamente com um software de processamento permite a criação dos (bio)sensores. Capazes de transformar, nesse caso, correntes geradas através de reações de oxi-redução em um sinal computacional que pode ser interpretado para entendimento de diversas reações que acontecem na superfície do eletrodo (COBBOLD, R. S. C. Transducers for Biomedical Measurements, 1974). [0006] A IUPAC ( International Union ofPure and Applied Chemistry) define como biossensor um instrumento integrado que é capaz de fornecer uma informação analítica específica, quantitativa ou semi-quantitativa, consistem da formação de um sistema envolvido por materiais biológicos, de grande variedade, integrados a sistemas eletrónicos. Os parâmetros mensurados e a especificidade do processo, caracterizam os tipos de materiais utilizados, tanto biológicos quanto eletrónicos (LAZCKA, O.; DEL CAMPO, F.J.; MUNOZ, F. X. Pathogen detection: a perspective of traditional methods and biosensors. Biossensors and Bioletronics, v. 22, p.1205-1217. 2007; MEFIROTRA, P. Biosensors and their applications - A review. Journal of Oral Biology and Craniofacial Research, v. 6, n. 2, p. 153-159, 2016). [0005] The electrochemistry technique can be considered an object of measurement of species of different natures and associated with a signal transducer system together with processing software allows the creation of (bio) sensors. Able to transform, in this case, currents generated through oxy-reduction reactions into a computational signal that can be interpreted to understand various reactions that take place on the electrode surface (COBBOLD, RSC Transducers for Biomedical Measurements, 1974). [0006] IUPAC (International Union of Pure and Applied Chemistry) defines an integrated instrument as a biosensor capable of providing specific analytical information, quantitative or semi-quantitative, consisting of the formation of a system surrounded by biological materials, of great variety, integrated with electronic systems. The measured parameters and the specificity of the process, characterize the types of materials used, both biological and electronic (LAZCKA, O .; DEL CAMPO, FJ; MUNOZ, FX Pathogen detection: a perspective of traditional methods and biosensors. Biossensors and Bioletronics, v .22, p.1205-1217. 2007; MEFIROTRA, P. Biosensors and their applications - A review. Journal of Oral Biology and Craniofacial Research, v. 6, n. 2, p. 153-159, 2016).
[0007] Quando comparados com as técnicas de diagnóstico existentes para doenças, os biossensores apresentam diversas vantagens, dentre elas a facilidade de manipulação, baixo custo de produção, rapidez no diagnóstico, alta sensibilidade e especificidade (SANTANA, L. K. L, RICARDO, P. C„ SERUDO, R. L., LASMAR, M. L., SANTOS, M. C.; Imunossensores eletroquímicos e suas aplicações. Scientia Amazónia, S.i, v. 6, n. 1 , p.31 -41 , 2017. [0007] When compared with existing diagnostic techniques for diseases, biosensors have several advantages, including ease of handling, low cost of production, rapid diagnosis, high sensitivity and specificity (SANTANA, LK L, RICARDO, P. C „SERUDO, RL, LASMAR, ML, SANTOS, MC; Electrochemical immunosensors and their applications. Scientia Amazónia, Si, v. 6, n. 1, p.31 -41, 2017.
[0008] O sucesso no desenvolvimento e construção de biossensores de forma eficiente exige que características como reprodutividade, sensibilidade, estabilidade, seletividade sejam cuidadosamente controladas. A otimização de tais parâmetros garante uma maior qualidade na aferição dada pelo sistema que está em criação (ALMEIDA, Fernando Luis de. Desenvolvimento de um sensor eletroquímico planar modificado com 1 -2 Diaminobenzeno (DAB) para monitoração de nitrito por FIA-automatizada. 2009. 176 f. Dissertação (Mestrado) - Curso de Mestrado em Engenharia Elétrica, Universidade de São Paulo, São Paulo, 2009). [0008] Success in the development and construction of biosensors efficiently requires characteristics such as reproducibility, sensitivity, stability, selectivity to be carefully controlled. The optimization of such parameters guarantees a higher quality in the measurement given by the system that is being created (ALMEIDA, Fernando Luis de. Development of a planar electrochemical sensor modified with 1 -2 Diaminobenzene (DAB) for monitoring nitrite by FIA-automated. 2009 176 f. Dissertation (Master's) - Master's Course in Electrical Engineering, University of São Paulo, São Paulo, 2009).
[0009] Levando em consideração todas essas características físico-químicas diretamente relacionadas com as propriedades do eletrodo, voltamos à dupla camada elétrica e a diferença de potencial controlados por fatores externos. Recentemente tem se adotado o uso de materiais nanotecnólogicos como possibilidade de modificação da superfície do eletrodo e consequente alteração nessas respostas, levando a uma estabilização e padronização dos resultados. Essa melhora pode estar relacionada com diferentes fatores, mas dois exemplos é o aumento da área ativa do eletrodo e uma melhora na condutividade do sistema. [0009] Taking into account all these physical-chemical characteristics directly related to the properties of the electrode, we return to the double electrical layer and the potential difference controlled by external factors. Recently, the use of nanotechnological materials has been adopted as a possibility to modify the electrode surface and consequent change in these responses, leading to a stabilization and standardization of results. This improvement may be related to different factors, but two examples are the increase in the active area of the electrode and an improvement in the conductivity of the system.
[00010] A patente BR 102015007505-6 A2 discute a modificação da superfície de eletrodos através da técnica de automontagem utilizando nanopartículas magnéticas revestidas com nanopartículas na construção de sensores diagnósticos para esquistossomose. [00010] The patent BR 102015007505-6 A2 discusses the modification of the electrode surface through the self-assembly technique using magnetic nanoparticles coated with nanoparticles in the construction of diagnostic sensors for schistosomiasis.
[0001 1] A patente BR 102012021218-8 A2 utiliza eletrodos impressos de tinta de carbono modificados depois entrar em contato com uma solução à base de uma base forte e agente reticulante. Nesse mesmo trabalho há a utilização de um filme polimérico de xiloglucana como pré-tratamento e estabilização na construção de um sensor diagnóstico para componentes tóxicos de Ricina. [0001 1] The patent BR 102012021218-8 A2 uses printed electrodes of modified carbon ink after coming into contact with a solution based on a strong base and crosslinking agent. In the same work, a polymeric xyloglucan film is used as pre-treatment and stabilization in the construction of a diagnostic sensor for toxic components of Ricina.
[00012] A patente BR 102016018862-8 A2 traz uma modificação diferente, eletrodos compósitos baseados em grafites e polímeros termoplásticos. Esses eletrodos são produzidos utilizando a técnica de dissolução e secagem e servem para determinar analitos orgânicos e inorgânicos e podem ser empregados em uma ampla faixa de pH e em diferentes meios eletrolíticos. [00012] The patent BR 102016018862-8 A2 brings a different modification, composite electrodes based on graphites and thermoplastic polymers. These electrodes are produced using the dissolution and drying technique and serve to determine organic and inorganic analytes and can be used over a wide pH range and in different electrolytic media.
[00013] A patente BR 102015028052-1 A2 descreve a polimerização eletroquímica de poli (ácido 3-hidroxifenolacético) por dispersão aquosa para modificação de eletrodos de ouro para formar uma matriz e hibridização de oligonucleotídeos na construção de biossensores. [00013] The patent BR 102015028052-1 A2 describes the electrochemical polymerization of poly (3-hydroxyphenolacetic acid) by aqueous dispersion for modification of gold electrodes to form a matrix and hybridization of oligonucleotides in the construction of biosensors.
[00014] O uso de materiais específicos que possam aumentar a condutibilidade da superfície do eletrodo é também uma alternativa de modificação. O aumento da condução de corrente no sistema eletroquímico pode influenciar diretamente o processo de oxi-redução da reação e a transferência de carga. É importante levar essas características em consideração uma vez que a amplificação do sinal pode melhorar a sensibilidade e seletividade do biossensor. [00014] The use of specific materials that can increase the conductivity of the electrode surface is also an alternative to modification. The increase in current conduction in the electrochemical system can directly influence the process of oxy-reduction of the reaction and the transfer of charge. It is important to take these characteristics into account since the amplification of the signal can improve the sensitivity and selectivity of the biosensor.
[00015] Pensando no uso desse tipo de material condutor, a patente US 201 10212321 A1 propôs a utilização de filmes poliméricos formados por nanofibras obtidos por eletrospinnig com nanotubos embebidos. [00015] Thinking about the use of this type of conductive material, the patent US 201 10212321 A1 proposed the use of polymeric films formed by nanofibers obtained by electrospinnig with embedded nanotubes.
[00016] A patente US 20130209807 A1 utiliza folhas de nanotubos de carbono modificados para modificação parcial ou total de eletrodos que podem ser aplicados em sensores, incluindo biossensores. [00016] US patent 20130209807 A1 uses modified carbon nanotube sheets for partial or total modification of electrodes that can be applied to sensors, including biosensors.
Descrição e detalhamento dos componentes da invenção Description and details of the components of the invention
[00017] Buscando associar os conceitos anteriormente descritos, a presente invenção visa desenvolver uma matriz de blendas poliméricas enriquecidas com nanomaterias e/ou compostos químicos como ferramenta de modificação da superfície de eletrodos“screen-printed” de grafite. [00018] A aquisição das micro e nanofibras que constituem a matriz polimérica baseou-se na produção de soluções de blendas poliméricas de polímeros hidrofóbicos como, por exemplo, o poli (ácido lático), PLA, e polímeros hidrofílicos como, por exemplo, o poli (etilenoglicol), PEG, mas não exclusivos a esses polímeros. As soluções podem ser enriquecidas com outros nanomateriais (como nanotubos e nanopartículas) e esses materiais podem ou não estar associados a compostos químicos, ambos em concentrações variáveis de 0,5 a 50% da massa total de polímero utilizada (m/m). Essas soluções serão injetadas através de um sistema de bicos concêntricos, preferivelmente, mas não exclusivos, a uma determinada taxa fixa de 10 a 750 uL/min, de maneira ideal entre 70 e 130 uL/min. Ao mesmo tempo, o bico externo liberará através de um sistema de gás comprimido (armazenado em cilindro ou produzido num compressor) o gás com pressão de 5 a 100 psi, que se encarrega de arrastar as soluções poliméricas enriquecidas (100/0 - 0/100% m/v ou v/v) transformando-as em fibras, ejetadas em direção ao coletor. [00017] Seeking to associate the concepts previously described, the present invention aims to develop a matrix of polymeric blends enriched with nanomaterials and / or chemical compounds as a tool for modifying the surface of graphite “screen-printed” electrodes. [00018] The acquisition of micro and nanofibers that constitute the polymeric matrix was based on the production of solutions of polymeric blends of hydrophobic polymers such as, for example, poly (lactic acid), PLA, and hydrophilic polymers, such as, poly (ethylene glycol), PEG, but not exclusive to these polymers. The solutions can be enriched with other nanomaterials (such as nanotubes and nanoparticles) and these materials may or may not be associated with chemical compounds, both in concentrations varying from 0.5 to 50% of the total polymer mass used (m / m). These solutions will be injected through a system of concentric nozzles, preferably, but not exclusive, at a fixed rate of 10 to 750 uL / min, ideally between 70 and 130 uL / min. At the same time, the external nozzle will release through a compressed gas system (stored in a cylinder or produced in a compressor) the gas with a pressure of 5 to 100 psi, which is responsible for dragging the enriched polymer solutions (100/0 - 0 / 100% m / v or v / v) transforming them into fibers, ejected towards the collector.
[00019] A estabilização e modificação da superfície do eletrodo se deu por eletrodeposição induzida pela passagem de corrente em ciclos repetidos na matriz em contato com a superfície do eletrodo a uma velocidade de varredura variando de 0,02 a 0,2V/s. [00019] The stabilization and modification of the electrode surface occurred through electrodeposition induced by the passage of current in repeated cycles in the matrix in contact with the electrode surface at a sweeping speed ranging from 0.02 to 0.2V / s.
[00020] Os métodos utilizados para o desenvolvimento dos processos e para validar a caracterização da matriz polimérica e a modificação da superfície do eletrodo estão descritas abaixo: [00021] Análises por Microscopia Eletrónica de Varredura: para determinar medir as dimensões e o tipo morfológico (fibrosa, particulada, porosa, etc.) dos materiais produzidos. [00020] The methods used to develop the processes and to validate the characterization of the polymeric matrix and the modification of the electrode surface are described below: [00021] Analysis by Scanning Electron Microscopy: to determine the dimensions and morphological type (fibrous, particulate, porous, etc.) of the materials produced.
[00022] Análises por FTIR: as análises por FTIR permitem determinar a presença dos materiais e/ou compostos químicos, incorporados nas fibras, através de suas bandas ou picos de absorbância na região do infravermelho. [00022] FTIR analysis: FTIR analysis allows the determination of the presence of materials and / or chemical compounds, incorporated in the fibers, through their bands or absorbance peaks in the infrared region.
[00023] Análises por DSC (Differential scanning calorimetry): permite avaliar as mudanças estruturais devido à incorporação das nanopartículas (e/ou nTC). Além disso, permite a avaliação do efeito plastificante do poli (etileno glicol) -PEG nas nanofibras, medidas através de sua temperatura de transição vítrea (Tg), cristalização (Tc) e fusão (Tm). Essas mudanças influenciam diretamente na cinética de liberação das nanopartículas (e/ou nTC) incorporado(s). [00023] Analysis by DSC (Differential scanning calorimetry): allows to evaluate the structural changes due to the incorporation of nanoparticles (and / or nTC). In addition, it allows the evaluation of the plasticizing effect of poly (ethylene glycol) -PEG on nanofibers, measured through their glass transition temperature (Tg), crystallization (Tc) and melting (Tm). These changes directly influence the release kinetics of the incorporated nanoparticles (and / or nTC).
[00024] Análises por TG (termogravimetria): permite, através de medidas de perdas de massa, em função da temperatura, determinar a liberação e/ou a presença de substâncias voláteis incorporadas às nanofibras, bem como a perda dessas substâncias em função do tempo e condição de armazenamento. [00024] Analyzes by TG (thermogravimetry): allows, through measurements of mass losses, as a function of temperature, to determine the release and / or presence of volatile substances incorporated into the nanofibers, as well as the loss of these substances as a function of time and storage condition.
[00025] Análise por voltametria cíclica: técnica em que se aplica um potencial sobre o eletrodo de trabalho e mede-se a corrente elétrica originada. Através dessa técnica é possível avaliar o perfil de oxi-redução formado. A modificação leva a um aumento na leitura de corrente medida. [00025] Cyclic voltammetry analysis: technique in which a potential is applied to the working electrode and the originating electric current is measured. Through this technique it is possible to evaluate the formed oxy-reduction profile. The modification leads to an increase in the measured current reading.
[00026] A invenção será melhor entendida com base nas figuras em anexo, onde: [00026] The invention will be better understood based on the attached figures, where:
A Figura 1 apresenta a micrografia da estrutura micro e nanofibrilar da matriz polimérica em questão. A Figura 2 exibe os gráficos de perda de massa e derivadas das perdas de massas dos materiais constituintes e da matriz polimérica adquiridos por termogravimetria, evidenciando o comportamento térmico até sua degradação. A Figura 3 evidencia as curvas térmicas obtidas por calorimetria exploratória diferencial (DSC), com o objetivo de avaliar o processamento dos materiais produzidos para a reivindicação em questão. Figure 1 shows the micrograph of the micro and nanofibrillar structure of the polymeric matrix in question. Figure 2 shows the graphs of mass loss and derived from the mass losses of the constituent materials and of the polymeric matrix acquired by thermogravimetry, showing the thermal behavior until its degradation. Figure 3 shows the thermal curves obtained by differential scanning calorimetry (DSC), in order to evaluate the processing of the materials produced for the claim in question.
A Figura 4 apresenta os gráficos da Espectroscopia no infravermelho por transformada de Fourier (FTIR), ao qual foi possível identificar as frequências de absorção dos grupos funcionais característicos dos materiais constituintes e das matrizes poliméricas. Figure 4 presents the graphs of Fourier Transform Infrared Spectroscopy (FTIR), to which it was possible to identify the absorption frequencies of the functional groups characteristic of the constituent materials and of the polymeric matrices.
A Figura 5 mostra um esquema do modelo de eletrodo utilizado. Em (A) o esquema ilustra as divisões dos eletrodos impressos: onde 1 é a área de trabalho; 2 o contra-eletrodo (ambos do mesmo material); 3 representa o eletrodo de referência revestido de prata. Em (B) o esquema ilustra a forma como a matriz polimérica é colocada sobre o eletrodo, na área de trabalho, para a funcionalização. Figure 5 shows a schematic of the electrode model used. In (A) the diagram illustrates the divisions of the printed electrodes: where 1 is the work area; 2 the counter electrode (both of the same material); 3 represents the silver-coated reference electrode. In (B) the diagram illustrates how the polymeric matrix is placed on the electrode, in the work area, for functionalization.
A Figura 6 ilustra três gráficos da leitura em voltametria cíclica. Em (A) as leituras foram feitas em dez eletrodos virgens diferentes, sem modificação na superfície, e não apresenta um padrão nas curvas lidas. Em (B) a leitura de voltametria cíclica foi realizada nos mesmos eletrodos após a modificação e nesse caso as curvas já demonstraram um comportamento padrão em todos os eletrodos. Em (C) a técnica de voltametria foi utilizada em eletrodos estabilizados após lavagens sucessivas. A Figura 7 é uma imagem de Microscopia Eletrónica de Varredura da superfície de trabalho do eletrodo virgem e do eletrodo modificado. As imagens (A), (C) e (E) se referem à superfície de um eletrodo virgem em diferentes aumentos. Em (B), D) e (F) as imagens são da superfície de um eletrodo modificado em diferentes aumentos. Figure 6 illustrates three graphs of the reading in cyclic voltammetry. In (A) the readings were made on ten different virgin electrodes, without modification on the surface, and there is no pattern in the curves read. In (B) the cyclic voltammetry reading was performed on the same electrodes after the modification and in this case the curves have already demonstrated a standard behavior in all electrodes. In (C) the voltammetry technique was used on stabilized electrodes after successive washes. Figure 7 is a Scanning Electron Microscopy image of the work surface of the virgin electrode and the modified electrode. The images (A), (C) and (E) refer to the surface of a virgin electrode in different magnifications. In (B), D) and (F) the images are of the surface of an electrode modified in different magnifications.
A Figura 8 é uma imagem e o respectivo gráfico de análise por EDS - capaz de analisar os componentes da superfície do eletrodo. Em (A) a imagem mostra o campo em que a análise por EDS foi feita e em (B) quais componentes químicos foram encontrados durante a análise e a respectiva quantidade em proporções para o eletrodo virgem. De maneira análoga, (C) e (D) representam respectivamente o campo em que a análise foi feita e a quantificação de elementos químicos para o eletrodo modificado. Figure 8 is an image and the respective EDS analysis graph - capable of analyzing the electrode surface components. In (A) the image shows the field in which the EDS analysis was performed and in (B) which chemical components were found during the analysis and the respective quantity in proportions for the virgin electrode. Similarly, (C) and (D) respectively represent the field in which the analysis was performed and the quantification of chemical elements for the modified electrode.
A Figura 9 representa os gráficos de leitura por voltametria cíclica com diferentes velocidades de varredura para determinação da área ativa do eletrodo utilizando a fórmula de Randles-Sevicik. (A) representa o gráfico de leitura de diferentes curvas de voltametria cíclica com velocidade de scan crescente para o eletrodo virgem, comparada com as leituras feitas em dois eletrodos com modificações diferentes (em C e E). As retas representadas nos gráficos (B), (D) e (F) são referentes às correntes de pico, obtidas das curvas de voltametria cíclica, para cada velocidade de scan. Figure 9 represents the graphs of reading by cyclic voltammetry with different scanning speeds to determine the active area of the electrode using the Randles-Sevicik formula. (A) represents the reading graph of different cyclic voltammetry curves with increasing scan speed for the virgin electrode, compared with the readings made on two electrodes with different modifications (in C and E). The lines represented in the graphs (B), (D) and (F) refer to the peak currents, obtained from the cyclic voltammetry curves, for each scan speed.
Na Figura 10 estão os gráficos representativos das áreas ativas dos eletrodos, antes e após a modificação com os diferentes tipos de matriz polimérica. Em (A) os dados estão em unidade de medida com valores absolutos e em (B) foi feita uma normalização dos mesmos dados para porcentagem tomando como referência o eletrodo virgem. As nomenclaturas de E-l a E-VII, visíveis tanto em (A) quanto em (B) se referem a diferentes tipos de combinações dos materiais para modificação da superfície do eletrodo. In Figure 10 are the graphs representing the active areas of the electrodes, before and after modification with the different types of polymeric matrix. In (A) the data are in unit of measure with absolute values and in (B) a normalization of the same data was made to percentage taking as reference the virgin electrode. The nomenclatures from El to E-VII, visible in both (A) and (B) refer to different types of material combinations for modifying the electrode surface.
A Figura 11 representa leituras de voltametria cíclica para diferentes fases de modificações da superfície do eletrodo, ao longo do processo. Tanto em (A) quanto em (B) a linha contínua representa o eletrodo virgem, sem modificação, e a linha pontilhada representa em (A) a modificação com a matriz polimérica e em (B) a adsorção de amostra após a modificação. Figure 11 represents cyclic voltammetry readings for different phases of changes in the electrode surface, throughout the process. In both (A) and (B) the continuous line represents the virgin electrode, without modification, and the dotted line represents in (A) the modification with the polymeric matrix and in (B) the sample adsorption after the modification.

Claims

REIVINDICAÇÕES
1 . MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED caracterizada por utilizar matriz polimérica com blendas de polímeros hidrofílicos e hidrofóbicos combinados na proporção de (0:100 a 50:50). 1 . MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE characterized by using polymeric matrix with blends of hydrophilic and hydrophobic polymers combined in the proportion of (0: 100 to 50:50).
2. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com a reivindicação 1 , caracterizada por utilizar polímeros hidrofílicos, como Polietilenoglicol, PEG, por exemplo. 2. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to claim 1, characterized by using hydrophilic polymers, such as Polyethylene glycol, PEG, for example.
3. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por utilizar polímeros hidrofóbicos, poli (ácido lático), PLA, por exemplo. 3. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any one of the preceding claims, characterized by using hydrophobic polymers, poly (lactic acid), PLA, for example.
4. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por enriquecimento da matriz com nanomateriais, como nanotubos e nanopartículas. 4. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any of the preceding claims, characterized by enrichment of the matrix with nanomaterials, such as nanotubes and nanoparticles.
5. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por ocorrer por eletrodeposição induzida pela passagem de corrente em ciclos repetidos na matriz em contato com a superfície do eletrodo a uma velocidade de varredura variando de 0,02 a 0,2V/s. 5. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any one of the preceding claims, characterized by occurring by electrodeposition induced by the passage of current in repeated cycles in the matrix in contact with the electrode surface at a sweeping speed ranging from 0, 02 to 0.2V / s.
6. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por aumentar a condutividade na superfície de eletrodos impressos. 6. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any of the preceding claims, characterized by increasing the conductivity on the surface of printed electrodes.
7. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por ser agente intermediário para adsorção de moléculas biológicas em eletrodos impressos. 7. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any of the preceding claims, characterized by be an intermediate agent for adsorption of biological molecules on printed electrodes.
8. MODIFICAÇÃO DA SUPERFÍCIE DE ELETRODOS SCREEN-PRINTED de acordo com qualquer uma das reivindicações anteriores, caracterizada por aumentar, melhorar e estabilizar o sinal das medidas eletroquímicas. 8. MODIFICATION OF THE SCREEN-PRINTED ELECTRODES SURFACE according to any of the preceding claims, characterized by increasing, improving and stabilizing the signal of electrochemical measurements.
PCT/BR2020/050150 2019-05-02 2020-05-04 Modification of the surface of screen-printed electrodes WO2020220106A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BRBR1020190089628 2019-05-02
BR102019008962-8A BR102019008962A2 (en) 2019-05-02 2019-05-02 modification of the surface of screen-printed electrodes

Publications (1)

Publication Number Publication Date
WO2020220106A1 true WO2020220106A1 (en) 2020-11-05

Family

ID=73028714

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/BR2020/050150 WO2020220106A1 (en) 2019-05-02 2020-05-04 Modification of the surface of screen-printed electrodes

Country Status (2)

Country Link
BR (1) BR102019008962A2 (en)
WO (1) WO2020220106A1 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007120442A2 (en) * 2003-07-25 2007-10-25 Dexcom, Inc. Dual electrode system for a continuous analyte sensor
BR102016018862A2 (en) * 2016-08-16 2018-03-06 Universidade Federal Do Rio De Janeiro - Ufrj GRAPHITE-BASED COMPOSITE ELECTRODES AND THERMOPLASTIC POLYMERS

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007120442A2 (en) * 2003-07-25 2007-10-25 Dexcom, Inc. Dual electrode system for a continuous analyte sensor
BR102016018862A2 (en) * 2016-08-16 2018-03-06 Universidade Federal Do Rio De Janeiro - Ufrj GRAPHITE-BASED COMPOSITE ELECTRODES AND THERMOPLASTIC POLYMERS

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZARE, Y ET AL.: "Polymer/metal nanocomposites for biomedical applications", MATERIALS SCI. AND ENGINEERING, 2016, pages 195 - 203, XP029365410, DOI: 10.1016/j.msec.2015.11.023 *

Also Published As

Publication number Publication date
BR102019008962A2 (en) 2020-11-10

Similar Documents

Publication Publication Date Title
Mugo et al. Flexible molecularly imprinted electrochemical sensor for cortisol monitoring in sweat
Lin et al. Polyaniline nanofiber humidity sensor prepared by electrospinning
Huang et al. Carbon dots and chitosan composite film based biosensor for the sensitive and selective determination of dopamine
Shin et al. Highly selective FET-type glucose sensor based on shape-controlled palladium nanoflower-decorated graphene
Ding et al. Electrospun nanofibrous membranes coated quartz crystal microbalance as gas sensor for NH3 detection
Si et al. Selective and sensitive determination of dopamine by composites of polypyrrole and graphene modified electrodes
CN104142361B (en) A kind of protein molecule engram poly ion liquid membrane electrochemical sensor
Zhang et al. Fabrication of poly (orthanilic acid)–multiwalled carbon nanotubes composite film-modified glassy carbon electrode and its use for the simultaneous determination of uric acid and dopamine in the presence of ascorbic acid
Li et al. Electrospun nanofibers for sensors
CN111118889A (en) Multifunctional flexible sensing fiber membrane and preparation method and application thereof
Wen et al. Fabrication of layer-by-layer assembled biomimetic nanochannels for highly sensitive acetylcholine sensing.
Li et al. Simultaneous determination of dopamine and uric acid in the presence of ascorbic acid using a gold electrode modified with carboxylated graphene and silver nanocube functionalized polydopamine nanospheres
CN103585004B (en) Nanometer sensing needle and manufacturing method thereof
Benachio et al. Employing molecularly imprinted polymers in the development of electroanalytical methodologies for antibiotic determination
CN1201146C (en) Electrochemical sensor for determining dopamine
Wang et al. Ultrasensitive electrochemical sensing of dopamine using reduced graphene oxide sheets decorated with p-toluenesulfonate-doped polypyrrole/Fe 3 O 4 nanospheres
Raza et al. Progress of wearable and flexible electrochemical biosensors with the aid of conductive nanomaterials
Zhang et al. Electrochemical sensor for procaine based on a glassy carbon electrode modified with poly-amidosulfonic acid and multi-walled carbon nanotubes
Yoon et al. Toxicity analysis of graphene nanoflakes by cell-based electrochemical sensing using an electrode modified with nanocomposite of graphene and Nafion
Al-Haidary et al. Development of polyaniline for sensor applications: A review
Yan et al. Rhombus-patterned flexible self-supported PVDF-based humidity sensor for respiratory monitoring
Bauer et al. Critical review of polymer and hydrogel deposition methods for optical and electrochemical bioanalytical sensors correlated to the sensor’s applicability in real samples
Zhang et al. Wearable chemical sensors based on 2D materials for healthcare applications
Zhou et al. A highly sensitive ammonia sensor based on spinous core–shell PCL–PANI fibers
Lee et al. Electrical detection-based analytic biodevice technology

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20799016

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20799016

Country of ref document: EP

Kind code of ref document: A1