Nanostructured Titanium Dioxide Surfaces for Electrochemical Biosensing

TiO2 electrochemical biosensors represent an option for biomolecules recognition associated with diseases, food or environmental contaminants, drug interactions and related topics. The relevance of TiO2 biosensors is due to the high selectivity and sensitivity that can be achieved. The development of electrochemical biosensors based on nanostructured TiO2 surfaces requires knowing the signal extracted from them and its relationship with the properties of the transducer, such as the crystalline phase, the roughness and the morphology of the TiO2 nanostructures. Using relevant literature published in the last decade, an overview of TiO2 based biosensors is here provided. First, the principal fabrication methods of nanostructured TiO2 surfaces are presented and their properties are briefly described. Secondly, the different detection techniques and representative examples of their applications are provided. Finally, the functionalization strategies with biomolecules are discussed. This work could contribute as a reference for the design of electrochemical biosensors based on nanostructured TiO2 surfaces, considering the detection technique and the experimental electrochemical conditions needed for a specific analyte.

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Electrochemical Biosensors for Cytokine Profiling: Recent Advancements and Possibilities in the Near Future

Biosensors ◽

10.3390/bios11030094 ◽

2021 ◽

Vol 11 (3) ◽

pp. 94

Author(s):

Nirmita Dutta ◽

Peter B. Lillehoj ◽

Pedro Estrela ◽

Gorachand Dutta

Keyword(s):

Immune System ◽

Cost Effective ◽

Anomalous Behavior ◽

Quantitative Detection ◽

Electrochemical Biosensors ◽

Aberrant Expression ◽

Detection Techniques ◽

Short Period ◽

User Friendly ◽

Cytokine Profiling

Cytokines are soluble proteins secreted by immune cells that act as molecular messengers relaying instructions and mediating various functions performed by the cellular counterparts of the immune system, by means of a synchronized cascade of signaling pathways. Aberrant expression of cytokines can be indicative of anomalous behavior of the immunoregulatory system, as seen in various illnesses and conditions, such as cancer, autoimmunity, neurodegeneration and other physiological disorders. Cancer and autoimmune diseases are particularly adept at developing mechanisms to escape and modulate the immune system checkpoints, reflected by an altered cytokine profile. Cytokine profiling can provide valuable information for diagnosing such diseases and monitoring their progression, as well as assessing the efficacy of immunotherapeutic regiments. Toward this goal, there has been immense interest in the development of ultrasensitive quantitative detection techniques for cytokines, which involves technologies from various scientific disciplines, such as immunology, electrochemistry, photometry, nanotechnology and electronics. This review focusses on one aspect of this collective effort: electrochemical biosensors. Among the various types of biosensors available, electrochemical biosensors are one of the most reliable, user-friendly, easy to manufacture, cost-effective and versatile technologies that can yield results within a short period of time, making it extremely promising for routine clinical testing.

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Label-Free Electrochemical Test of Protease Interaction with a Peptide Substrate Modified Gold Electrode

Chemosensors ◽

10.3390/chemosensors9080199 ◽

2021 ◽

Vol 9 (8) ◽

pp. 199

Author(s):

Anna Wcisło ◽

Izabela Małuch ◽

Paweł Niedziałkowski ◽

Tadeusz Ossowski ◽

Adam Prahl

Keyword(s):

Gold Electrode ◽

High Selectivity ◽

Electrode Materials ◽

Electrochemical Biosensors ◽

Electrochemical Characteristics ◽

Label Free ◽

Peptide Substrate ◽

Electrochemical Test ◽

Experimental Conditions ◽

Spectrofluorimetric Method

Efficient deposition of biomolecules on the surface, maintaining their full activity and stability, is a most significant factor in biosensor construction. For this reason, more and more research is focused on the development of electrochemical biosensors that have the ability to electrically detect adsorbed molecules on electrode surface with high selectivity and sensitivity. The presented research aims to develop an efficient methodology that allows quantification of processes related to the evaluation of enzyme activity (proprotein convertase) using electrochemical methods. In this study we used impedance spectroscopy to investigate the immobilization of peptide substrate (Arg-Val-Arg-Arg) modified with 11-mercaptoundecanoic acid on the surface of gold electrode. Both the synthesis of the peptide substrate as well as the full electrochemical characteristics of the obtained electrode materials have been described. Experimental conditions, including concentration of peptide substrate immobilization, modification time, linker, and the presence of additional blocking groups have been optimized. The main advantages of the described method is that it makes it possible to observe the peptide substrate–enzyme interaction without the need to use fluorescent labels. This also allows observation of this interaction at a very low concentration. Both of these factors make this new technique competitive with the standard spectrofluorimetric method.

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Photodetector based on Rutile and Anatase TiO2 nanostructures/n-Si Heterojunction

Journal of Physics Conference Series ◽

10.1088/1742-6596/2114/1/012025 ◽

2021 ◽

Vol 2114 (1) ◽

pp. 012025

Author(s):

S A Hamdan ◽

I M Ibrahim ◽

I M Ali

Keyword(s):

Titanium Dioxide ◽

Optical Absorption ◽

Ideality Factor ◽

Anatase Tio2 ◽

Optical Absorption Spectra ◽

Hydrothermal Technique ◽

Peak Absorption ◽

Rectification Factor ◽

Hall Effect Measurements ◽

Tio2 Nanostructures

Abstract Rutile and anatase titanium dioxide TiO2 nanostructures has been prepared successfully by hydrothermal technique. Also Rutile and anatase TiO2/n-Si heterojunction detector (HJ) has been fabricated. Hall Effect measurements confirmed that prepared films are n-type. The optical absorption spectra showed the prepared films have peak absorption in UV region. TiO2/n-Si heterojunction had exhibited diode-like rectifying I-V behaviour in the dark as well as under the illumination. Ideality factor greater than 2 and rectification factor for Rutile TiO2/n-Si HJ is equal 32.0961 higher than anatase TiO2/n-Si HJ. Photodetetor based on rutile TiO2/n-Si HJ showed higher responsivity and incident photon-to-current efficiency (IPCE) than photodetector based on anatase TiO2/n-Si HJ. Photodetetor based on rutile TiO2/n-Si HJ has responsivity is 69.11Amp/W at 570 nm and IPCE is 21.2%at 370nm and 1.38% at 570nm. For the purpose of investigating the impacts of TiO2 crystal phase upon the performance of the device despite the fact that rutile has a lower band gap compared to anatase, rutile exhibits better photovoltaic activity due to its higher specific surface area.

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Application of Electrochemical Aptasensors toward Clinical Diagnostics, Food, and Environmental Monitoring: Review

Sensors ◽

10.3390/s19245435 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5435 ◽

Cited By ~ 7

Author(s):

Zhanhong Li ◽

Mona A. Mohamed ◽

A. M. Vinu Mohan ◽

Zhigang Zhu ◽

Vinay Sharma ◽

...

Keyword(s):

Environmental Monitoring ◽

Biomedical Application ◽

Analytical Techniques ◽

Clinical Diagnostics ◽

Cardiac Biomarkers ◽

Research Progress ◽

Electrochemical Biosensors ◽

Recognition Element ◽

Clinical Biomarkers ◽

Electrochemical Biosensing

Aptamers are synthetic bio-receptors of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) origin selected by the systematic evolution of ligands (SELEX) process that bind a broad range of target analytes with high affinity and specificity. So far, electrochemical biosensors have come up as a simple and sensitive method to utilize aptamers as a bio-recognition element. Numerous aptamer based sensors have been developed for clinical diagnostics, food, and environmental monitoring and several other applications are under development. Aptasensors are capable of extending the limits of current analytical techniques in clinical diagnostics, food, and environmental sample analysis. However, the potential applications of aptamer based electrochemical biosensors are unlimited; current applications are observed in the areas of food toxins, clinical biomarkers, and pesticide detection. This review attempts to enumerate the most representative examples of research progress in aptamer based electrochemical biosensing principles that have been developed in recent years. Additionally, this account will discuss various current developments on aptamer-based sensors toward heavy metal detection, for various cardiac biomarkers, antibiotics detection, and also on how the aptamers can be deployed to couple with antibody-based assays as a hybrid sensing platform. Aptamers can be used in various applications, however, this account will focus on the recent advancements made toward food, environmental, and clinical diagnostic application. This review paper compares various electrochemical aptamer based sensor detection strategies that have been applied so far and used as a state of the art. As illustrated in the literature, aptamers have been utilized extensively for environmental, cancer biomarker, biomedical application, and antibiotic detection and thus have been extensively discussed in this article.

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Effects of Particle Size and Crystalline Phase on Lead Adsorption to Titanium Dioxide Nanoparticles

Environmental Engineering Science ◽

10.1089/ees.2007.24.85 ◽

2007 ◽

Vol 24 (1) ◽

pp. 85-95 ◽

Cited By ~ 107

Author(s):

Daniel E. Giammar ◽

Carolyn J. Maus ◽

Liyun Xie

Keyword(s):

Particle Size ◽

Titanium Dioxide ◽

Crystalline Phase ◽

Titanium Dioxide Nanoparticles ◽

Lead Adsorption

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Effect of Sputtering Pressure on Optimization of Titanium Dioxide Nanostructures Prepared by RF Magnetron Sputtering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.667.452 ◽

2013 ◽

Vol 667 ◽

pp. 452-457 ◽

Cited By ~ 1

Author(s):

N.A.M. Asib ◽

Mohamed Zahidi Musa ◽

Saifollah Abdullah ◽

Mohamad Rusop

Keyword(s):

Surface Roughness ◽

Titanium Dioxide ◽

Magnetron Sputtering ◽

Visible Region ◽

Rf Magnetron Sputtering ◽

Transmission Spectra ◽

Cross Sectional ◽

Vis Spectroscopy ◽

Sputtering Pressure ◽

Tio2 Nanostructures

Titanium dioxide (TiO2) nanostructures were deposited on glass substrate by Radio Frequency (RF) magnetron sputtering. The samples deposited at various sputtering pressures and annealed at 723 K, were characterized using Atomic Force Microscope (AFM) to observe the surface morphology and topology, roughness properties and cross-sectional of TiO2 nanostructures, Field Emission Scanning Electrons Microscope (FESEM) to observe the particle sizes of TiO2 nanostructures and UV-vis spectroscopy to record the UV-vis transmission spectra. The aim of this paper is to determine which parameter of sputtering pressures influence the optimization of TiO2 nanostructures. AFM images show that the surface roughness of the samples decreases as the working pressures of sputtering increases. From FESEM images, it can be deduced that the higher the sputtering pressure, the smaller the particle size is. All the samples are highly transmittance with an average transmittance higher than 80% in the visible region as recorded by UV-vis transmission spectra. The relatively high transmittance of the sample indicates its low surface roughness and good homogeneity. For optimum TiO2 nanostructures deposited at various RF pressures it has the lowest surface roughness and the smallest TiO2 size particles with the indirect optical band gap of 3.41 eV.

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Electrochemical Sensors and Biosensors for the Analysis of Tea Components: A Bibliometric Review

Frontiers in Chemistry ◽

10.3389/fchem.2021.818461 ◽

2022 ◽

Vol 9 ◽

Author(s):

Jinhua Shao ◽

Chao Wang ◽

Yiling Shen ◽

Jinlei Shi ◽

Dongqing Ding

Keyword(s):

Bibliometric Analysis ◽

High Performance ◽

Electrochemical Sensors ◽

Materials Science ◽

Low Cost ◽

Relevant Literature ◽

Electrochemical Techniques ◽

High Sensitivity ◽

Electrochemical Analysis ◽

Electrochemical Biosensing

Tea is a popular beverage all around the world. Tea composition, quality monitoring, and tea identification have all been the subject of extensive research due to concerns about the nutritional value and safety of tea intake. In the last 2 decades, research into tea employing electrochemical biosensing technologies has received a lot of interest. Despite the fact that electrochemical biosensing is not yet the most widely utilized approach for tea analysis, it has emerged as a promising technology due to its high sensitivity, speed, and low cost. Through bibliometric analysis, we give a systematic survey of the literature on electrochemical analysis of tea from 1994 to 2021 in this study. Electrochemical analysis in the study of tea can be split into three distinct stages, according to the bibliometric analysis. After chromatographic separation of materials, electrochemical techniques were initially used only as a detection tool. Many key components of tea, including as tea polyphenols, gallic acid, caffeic acid, and others, have electrochemical activity, and their electrochemical behavior is being investigated. High-performance electrochemical sensors have steadily become a hot research issue as materials science, particularly nanomaterials, and has progressed. This review not only highlights these processes, but also analyzes and contrasts the relevant literature. This evaluation also provides future views in this area based on the bibliometric findings.

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RGD-modified dihydrolipoamide dehydrogenase conjugated to titanium dioxide nanoparticles –switchableintegrin-targeted photodynamic treatment of melanoma cells

RSC Advances ◽

10.1039/c7ra13777j ◽

2018 ◽

Vol 8 (17) ◽

pp. 9112-9119 ◽

Cited By ~ 7

Author(s):

Avraham Dayan ◽

Gideon Fleminger ◽

Osnat Ashur-Fabian

Keyword(s):

Titanium Dioxide ◽

Photodynamic Therapy ◽

Cancer Cells ◽

High Selectivity ◽

Titanium Dioxide Nanoparticles ◽

Melanoma Cells ◽

Dihydrolipoamide Dehydrogenase ◽

Photodynamic Treatment ◽

Targeted Photodynamic Therapy

This work presents a UVA switchable integrin-targeted photodynamic therapy in melanoma, composed of an RGD-modified DLDH conjugated to TiO2nanoparticles, with high selectivity towards integrin-expressing cancer cells.

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