Construction of Biosensors Using Nano- and Microtechnology

A special issue of Biosensors (ISSN 2079-6374). This special issue belongs to the section "Nano- and Micro-Technologies in Biosensors".

Deadline for manuscript submissions: closed (30 June 2023) | Viewed by 37341

Special Issue Editor

Department of Chemistry, University of Patras, Rio, 26504 Patras, Greece
Interests: biosensors; lateral flow assays; nanotechnology in biosensing; analytical methods; diagnostics; genomics; liquid biopsy; food authentication
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Nano- and microtechnology-based biosensors are state-of-the-art emerging technologies and promising alternatives to conventional methods. Micro- and nanostructured sophisticated systems exhibit great advantages in terms of their cost-effectiveness, the simple and rapid analysis they facilitate, the ease of their fabrication, their portability, increased detectability, high sensitivity, specificity, precision and robustness, as well as their increased capability for multiplexing. Along with their rapid development and structural flexibility, micro- and nanomaterials are ideal miniaturized sensing platforms for use in the construction of novel biosensors. Micro- and nanomaterials have been incorporated into applications concerning biosensors for signal enhancement, as their use avoids enzymatic reactions or multiple enhancement steps. Signal enhancement is mainly attributed to their high surface-to-volume ratio and their excellent properties. Moreover, these materials provide excellent solid support for the ease of surface modification and (bio)molecular immobilization for the analysis of various targets and numerous interdisciplinary applications.

Dr. Despina Kalogianni
Guest Editor

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Keywords

  • gold nanoparticles
  • gold nanostructures
  • graphene oxide
  • carbon dots
  • carbon nanotubes
  • carbon nanodots
  • copper nanoparticles
  • silica nanoparticles
  • silver nanoparticles
  • magnetic nanoparticles
  • quantum dots
  • molybdenum disulfide (MoS2) nanostructures
  • metal-organic frameworks (MOFs)
  • matal oxide nanoparticles
  • microspheres
  • other nano- and microstructures
  • optical sensors
  • electrochemical sensors
  • lateral flow assays

Published Papers (13 papers)

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Research

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12 pages, 7695 KiB  
Article
pH Quantification in Human Dermal Interstitial Fluid Using Ultra-Thin SOI Silicon Nanowire ISFETs and a High-Sensitivity Constant-Current Approach
by Yann Sprunger, Luca Capua, Thomas Ernst, Sylvain Barraud, Didier Locca, Adrian Ionescu and Ali Saeidi
Biosensors 2023, 13(10), 908; https://doi.org/10.3390/bios13100908 - 27 Sep 2023
Viewed by 1076
Abstract
In this paper, we propose a novel approach to utilize silicon nanowires as high-sensitivity pH sensors. Our approach works based on fixing the current bias of silicon nanowires Ion Sensitive Field Effect Transistors (ISFETs) and monitor the resulting drain voltage as the sensing [...] Read more.
In this paper, we propose a novel approach to utilize silicon nanowires as high-sensitivity pH sensors. Our approach works based on fixing the current bias of silicon nanowires Ion Sensitive Field Effect Transistors (ISFETs) and monitor the resulting drain voltage as the sensing signal. By fine tuning the injected current levels, we can optimize the sensing conditions according to different sensor requirements. This method proves to be highly suitable for real-time and continuous measurements of biomarkers in human biofluids. To validate our approach, we conducted experiments, with real human sera samples to simulate the composition of human interstitial fluid (ISF), using both the conventional top-gate approach and the optimized constant current method. We successfully demonstrated pH sensing within the physiopathological range of 6.5 to 8, achieving an exceptional level of accuracy in this complex matrix. Specifically, we obtained a maximum error as low as 0.92% (equivalent to 0.07 pH unit) using the constant-current method at the optimal current levels (1.71% for top-gate). Moreover, by utilizing different pools of human sera with varying total protein content, we demonstrated that the protein content among patients does not impact the sensors’ performance in pH sensing. Furthermore, we tested real-human ISF samples collected from volunteers. The obtained accuracy in this scenario was also outstanding, with an error as low as 0.015 pH unit using the constant-current method and 0.178 pH unit in traditional top-gate configuration. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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18 pages, 5488 KiB  
Article
Characterization of Benchtop-Fabricated Arrays of Nanowrinkled Surface Electrodes as a Nitric Oxide Electrochemical Sensor
by Cindy Peto-Gutiérrez, Genaro Vázquez-Victorio and Mathieu Hautefeuille
Biosensors 2023, 13(8), 794; https://doi.org/10.3390/bios13080794 - 07 Aug 2023
Viewed by 930
Abstract
In this work, we present an accessible benchtop fabrication technique to obtain a planar array of gold nanowrinkled surface electrodes (ANSE) for the construction of electrochemical cells, specifically to monitor soluble biomarkers of interest in cell culture environments. We present a complete characterization [...] Read more.
In this work, we present an accessible benchtop fabrication technique to obtain a planar array of gold nanowrinkled surface electrodes (ANSE) for the construction of electrochemical cells, specifically to monitor soluble biomarkers of interest in cell culture environments. We present a complete characterization of the array and its response as an electrochemical cell. To validate our sensor, we evaluated the device sensitivity to detect nitric oxide (NO), an important molecule produced by endothelial cells as a response to environmental signals such as mechanics and growth factors. While testing measurements of nitric oxide in aqueous solutions with isotonic salt concentrations, we evidenced the influence of the environmental conditions for such electrochemical measurements, showing that the aqueous medium, usually not accounted for, significantly impacts the outcome. Finally, we present the application of the electrochemical sensor for the detection of nitric oxide released from stimulated endothelial cells as a proof of concept. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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13 pages, 1856 KiB  
Article
Mach-Zehnder Interferometric Immunosensor for Detection of Aflatoxin M1 in Milk, Chocolate Milk, and Yogurt
by Michailia Angelopoulou, Dimitra Kourti, Konstantinos Misiakos, Anastasios Economou, Panagiota Petrou and Sotirios Kakabakos
Biosensors 2023, 13(6), 592; https://doi.org/10.3390/bios13060592 - 30 May 2023
Cited by 1 | Viewed by 2576
Abstract
Aflatoxin M1 (AFM1) is detected in the milk of animals after ingestion of aflatoxin B1-contaminated food; since 2002, it has been categorized as a group I carcinogen. In this work, a silicon-based optoelectronic immunosensor for the detection of AFM1 in milk, chocolate milk, [...] Read more.
Aflatoxin M1 (AFM1) is detected in the milk of animals after ingestion of aflatoxin B1-contaminated food; since 2002, it has been categorized as a group I carcinogen. In this work, a silicon-based optoelectronic immunosensor for the detection of AFM1 in milk, chocolate milk, and yogurt has been developed. The immunosensor consists of ten Mach–Zehnder silicon nitride waveguide interferometers (MZIs) integrated on the same chip with the respective light sources, and an external spectrophotometer for transmission spectra collection. The sensing arm windows of MZIs are bio-functionalized after chip activation with aminosilane by spotting an AFM1 conjugate with bovine serum albumin. For AFM1 detection, a three-step competitive immunoassay is employed, including the primary reaction with a rabbit polyclonal anti-AFM1 antibody, followed by biotinylated donkey polyclonal anti-rabbit IgG antibody and streptavidin. The assay duration was 15 min with limits of detection of 0.005 ng/mL in both full-fat and chocolate milk, and 0.01 ng/mL in yogurt, which are lower than the maximum allowable concentration of 0.05 ng/mL set by the European Union. The assay is accurate (% recovery values 86.7–115) and repeatable (inter- and intra-assay variation coefficients <8%). The excellent analytical performance of the proposed immunosensor paves the way for accurate on-site AFM1 determination in milk. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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16 pages, 4596 KiB  
Article
Framing of Poly(arylene-ethynylene) around Carbon Nanotubes and Iodine Doping for the Electrochemical Detection of Dopamine
by Jose Paul, Md Moniruzzaman and Jongsung Kim
Biosensors 2023, 13(3), 308; https://doi.org/10.3390/bios13030308 - 22 Feb 2023
Cited by 4 | Viewed by 1501
Abstract
Dopamine (DA), an organic biomolecule that acts as both a hormone and a neurotransmitter, is essential in regulating emotions and metabolism in living organisms. The accurate determination of DA is important because it indicates early signs of serious neurological disorders. Covalent organic frameworks [...] Read more.
Dopamine (DA), an organic biomolecule that acts as both a hormone and a neurotransmitter, is essential in regulating emotions and metabolism in living organisms. The accurate determination of DA is important because it indicates early signs of serious neurological disorders. Covalent organic frameworks (COFs) and metal–organic frameworks (MOFs) have received considerable attention in recent years as promising porous materials with an unrivaled degree of tunability for electrochemical biosensing applications. This study adopted a solvothermal strategy for the synthesis of a conjugated microporous poly(arylene ethynylene)-4 (CMP-4) network using the Sonagashira–Hagihara cross-coupling reaction. To increase the crystallinity and electrical conductivity of the material, CMP-4 was enveloped around carbon nanotubes (CNTs), followed by iodine doping. When used as an electrochemical probe, the as-synthesized material (I2-CMP-CNT-4) exhibited excellent selectivity and sensitivity to dopamine in the phosphate-buffered solution. The detection limits of the electrochemical sensor were 1 and 1.7 μM based on cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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13 pages, 4491 KiB  
Article
Visual and Ultrasensitive Detection of a Coronavirus Using a Gold Nanorod Probe under Dark Field
by Xuejia Qian, Yuanzhao Shen, Jiasheng Yuan, Chih-Tsung Yang and Xin Zhou
Biosensors 2022, 12(12), 1146; https://doi.org/10.3390/bios12121146 - 08 Dec 2022
Viewed by 1533
Abstract
Porcine epidemic diarrhea virus (PEDV), a coronavirus that causes highly infectious intestinal diarrhea in piglets, has led to severe economic losses worldwide. Rapid diagnosis and timely supervision are significant in the prophylaxis of PEDV. Herein, we proposed a gold-nanorod (GNR) probe-assisted counting method [...] Read more.
Porcine epidemic diarrhea virus (PEDV), a coronavirus that causes highly infectious intestinal diarrhea in piglets, has led to severe economic losses worldwide. Rapid diagnosis and timely supervision are significant in the prophylaxis of PEDV. Herein, we proposed a gold-nanorod (GNR) probe-assisted counting method using dark field microscopy (DFM). The antibody-functionalized silicon chips were prepared to capture PEDV to form sandwich structures with GNR probes for imaging under DFM. Results show that our DFM-based assay for PEDV has a sensitivity of 23.80 copies/μL for simulated real samples, which is very close to that of qPCR in this study. This method of GNR probes combined with DFM for quantitative detection of PEDV not only has strong specificity, good repeatability, and a low detection limit, but it also can be implemented for rapid on-site detection of the pathogens. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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13 pages, 4306 KiB  
Article
Electrochemical Ultrasensitive Sensing of Uric Acid on Non-Enzymatic Porous Cobalt Oxide Nanosheets-Based Sensor
by Sakeena Masrat, Vandana Nagal, Marya Khan, Iqra Moid, Shamshad Alam, Kiesar Sideeq Bhat, Ajit Khosla and Rafiq Ahmad
Biosensors 2022, 12(12), 1140; https://doi.org/10.3390/bios12121140 - 07 Dec 2022
Cited by 8 | Viewed by 2048
Abstract
Transition metal oxide (TMO)-based nanomaterials are effectively utilized to fabricate clinically useful ultra-sensitive sensors. Different nanostructured nanomaterials of TMO have attracted a lot of interest from researchers for diverse applications. Herein, we utilized a hydrothermal method to develop porous nanosheets of cobalt oxide. [...] Read more.
Transition metal oxide (TMO)-based nanomaterials are effectively utilized to fabricate clinically useful ultra-sensitive sensors. Different nanostructured nanomaterials of TMO have attracted a lot of interest from researchers for diverse applications. Herein, we utilized a hydrothermal method to develop porous nanosheets of cobalt oxide. This synthesis method is simple and low temperature-based. The morphology of the porous nanosheets like cobalt oxide was investigated in detail using FESEM and TEM. The morphological investigation confirmed the successful formation of the porous nanosheet-like nanostructure. The crystal characteristic of porous cobalt oxide nanosheets was evaluated by XRD analysis, which confirmed the crystallinity of as-synthesized cobalt oxide nanosheets. The uric acid sensor fabrication involves the fixing of porous cobalt oxide nanosheets onto the GCE (glassy carbon electrode). The non-enzymatic electrochemical sensing was measured using CV and DPV analysis. The application of DPV technique during electrochemical testing for uric acid resulted in ultra-high sensitivity (3566.5 µAmM−1cm−2), which is ~7.58 times better than CV-based sensitivity (470.4 µAmM−1cm−2). Additionally, uric acid sensors were tested for their selectivity and storage ability. The applicability of the uric acid sensors was tested in the serum sample through standard addition and recovery of known uric acid concentration. This ultrasensitive nature of porous cobalt oxide nanosheets could be utilized to realize the sensing of other biomolecules. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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13 pages, 2208 KiB  
Article
A Molecular Lateral Flow Assay for SARS-CoV-2 Quantitative Detection
by Panagiotis Maglaras, Ioannis Lilis, Fotini Paliogianni, Vasiliki Bravou and Despina P. Kalogianni
Biosensors 2022, 12(11), 926; https://doi.org/10.3390/bios12110926 - 26 Oct 2022
Cited by 3 | Viewed by 2027
Abstract
Since the onset of the SARS-CoV-2 pandemic, several COVID-19 detection methods, both commercially available and in the lab, have been developed using different biomolecules as analytes and different detection and sampling methods with high analytical performance. Developing novel COVID-19 detection assays is an [...] Read more.
Since the onset of the SARS-CoV-2 pandemic, several COVID-19 detection methods, both commercially available and in the lab, have been developed using different biomolecules as analytes and different detection and sampling methods with high analytical performance. Developing novel COVID-19 detection assays is an exciting research field, as rapid accurate diagnosis is a valuable tool to control the current pandemic, and also because the acquired knowledge can be deployed for facing future infectious outbreaks. We here developed a novel gold-nanoparticle-based nucleic acid lateral flow assay for the rapid, visual, and quantitative detection of SARS-CoV-2. Our method was based on the use of a DNA internal standard (competitor) for quantification and involved RT-PCR, the hybridization of biotinylated PCR products to specific oligonucleotide probes, and detection with a dual lateral flow assay using gold nanoparticles conjugated to an anti-biotin antibody as reporters. The developed test allowed for rapid detection by the naked eye and the simultaneous quantification of SARS-CoV-2 in nasopharyngeal swabs with high specificity, detectability, and repeatability. This novel molecular strip test for COVID-19 detection represents a simple, cost-effective, and accurate rapid test that is very promising to be used as a future diagnostic tool. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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15 pages, 4225 KiB  
Article
Water–Air Interface to Mimic In Vitro Tumoral Cell Migration in Complex Micro-Environments
by Martina Conti, Ilaria Bolzan, Simone Dal Zilio, Pietro Parisse, Laura Andolfi and Marco Lazzarino
Biosensors 2022, 12(10), 822; https://doi.org/10.3390/bios12100822 - 03 Oct 2022
Cited by 1 | Viewed by 1281
Abstract
The long-known role of cell migration in physiological and pathological contexts still requires extensive research to be fully understood, mainly because of the intricate interaction between moving cells and their surroundings. While conventional assays fail to capture this complexity, recently developed 3D platforms [...] Read more.
The long-known role of cell migration in physiological and pathological contexts still requires extensive research to be fully understood, mainly because of the intricate interaction between moving cells and their surroundings. While conventional assays fail to capture this complexity, recently developed 3D platforms better reproduce the cellular micro-environment, although often requiring expensive and time-consuming imaging approaches. To overcome these limitations, we developed a novel approach based on 2D micro-patterned substrates, compatible with conventional microscopy analysis and engineered to create micro-gaps with a length of 150 µm and a lateral size increasing from 2 to 8 µm, where a curved water–air interface is created on which cells can adhere, grow, and migrate. The resulting hydrophilic/hydrophobic interfaces, variable surface curvatures, spatial confinements, and size values mimic the complex micro-environment typical of the extracellular matrix in which aggressive cancer cells proliferate and migrate. The new approach was tested with two breast cancer cell lines with different invasive properties. We observed that invasive cells (MDA-MB-231) can align along the pattern and modify both their morphology and their migration rate according to the size of the water meniscus, while non-invasive cells (MCF-7) are only slightly respondent to the surrounding micro-environment. Moreover, the selected pattern highlighted a significative matrix deposition process connected to cell migration. Although requiring further optimizations, this approach represents a promising tool to investigate cell migration in complex environments. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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Review

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32 pages, 6671 KiB  
Review
Nanotechnology-Enabled Biosensors: A Review of Fundamentals, Design Principles, Materials, and Applications
by Manickam Ramesh, Ravichandran Janani, Chinnaiyan Deepa and Lakshminarasimhan Rajeshkumar
Biosensors 2023, 13(1), 40; https://doi.org/10.3390/bios13010040 - 27 Dec 2022
Cited by 42 | Viewed by 9255
Abstract
Biosensors are modern engineering tools that can be widely used for various technological applications. In the recent past, biosensors have been widely used in a broad application spectrum including industrial process control, the military, environmental monitoring, health care, microbiology, and food quality control. [...] Read more.
Biosensors are modern engineering tools that can be widely used for various technological applications. In the recent past, biosensors have been widely used in a broad application spectrum including industrial process control, the military, environmental monitoring, health care, microbiology, and food quality control. Biosensors are also used specifically for monitoring environmental pollution, detecting toxic elements’ presence, the presence of bio-hazardous viruses or bacteria in organic matter, and biomolecule detection in clinical diagnostics. Moreover, deep medical applications such as well-being monitoring, chronic disease treatment, and in vitro medical examination studies such as the screening of infectious diseases for early detection. The scope for expanding the use of biosensors is very high owing to their inherent advantages such as ease of use, scalability, and simple manufacturing process. Biosensor technology is more prevalent as a large-scale, low cost, and enhanced technology in the modern medical field. Integration of nanotechnology with biosensors has shown the development path for the novel sensing mechanisms and biosensors as they enhance the performance and sensing ability of the currently used biosensors. Nanoscale dimensional integration promotes the formulation of biosensors with simple and rapid detection of molecules along with the detection of single biomolecules where they can also be evaluated and analyzed critically. Nanomaterials are used for the manufacturing of nano-biosensors and the nanomaterials commonly used include nanoparticles, nanowires, carbon nanotubes (CNTs), nanorods, and quantum dots (QDs). Nanomaterials possess various advantages such as color tunability, high detection sensitivity, a large surface area, high carrier capacity, high stability, and high thermal and electrical conductivity. The current review focuses on nanotechnology-enabled biosensors, their fundamentals, and architectural design. The review also expands the view on the materials used for fabricating biosensors and the probable applications of nanotechnology-enabled biosensors. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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37 pages, 3405 KiB  
Review
The Roadmap of Graphene-Based Sensors: Electrochemical Methods for Bioanalytical Applications
by Ghazala Ashraf, Ayesha Aziz, Tayyaba Iftikhar, Zi-Tao Zhong, Muhammad Asif and Wei Chen
Biosensors 2022, 12(12), 1183; https://doi.org/10.3390/bios12121183 - 19 Dec 2022
Cited by 6 | Viewed by 2493
Abstract
Graphene (GR) has engrossed immense research attention as an emerging carbon material owing to its enthralling electrochemical (EC) and physical properties. Herein, we debate the role of GR-based nanomaterials (NMs) in refining EC sensing performance toward bioanalytes detection. Following the introduction, we briefly [...] Read more.
Graphene (GR) has engrossed immense research attention as an emerging carbon material owing to its enthralling electrochemical (EC) and physical properties. Herein, we debate the role of GR-based nanomaterials (NMs) in refining EC sensing performance toward bioanalytes detection. Following the introduction, we briefly discuss the GR fabrication, properties, application as electrode materials, the principle of EC sensing system, and the importance of bioanalytes detection in early disease diagnosis. Along with the brief description of GR-derivatives, simulation, and doping, classification of GR-based EC sensors such as cancer biomarkers, neurotransmitters, DNA sensors, immunosensors, and various other bioanalytes detection is provided. The working mechanism of topical GR-based EC sensors, advantages, and real-time analysis of these along with details of analytical merit of figures for EC sensors are discussed. Last, we have concluded the review by providing some suggestions to overcome the existing downsides of GR-based sensors and future outlook. The advancement of electrochemistry, nanotechnology, and point-of-care (POC) devices could offer the next generation of precise, sensitive, and reliable EC sensors. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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46 pages, 8128 KiB  
Review
Progress of Enzymatic and Non-Enzymatic Electrochemical Glucose Biosensor Based on Nanomaterial-Modified Electrode
by Noorhashimah Mohamad Nor, Nur Syafinaz Ridhuan and Khairunisak Abdul Razak
Biosensors 2022, 12(12), 1136; https://doi.org/10.3390/bios12121136 - 06 Dec 2022
Cited by 29 | Viewed by 5802
Abstract
This review covers the progress of nanomaterial-modified electrodes for enzymatic and non-enzymatic glucose biosensors. Fundamental insights into glucose biosensor components and the crucial factors controlling the electrochemical performance of glucose biosensors are discussed in detail. The metal, metal oxide, and hybrid/composite nanomaterial fabrication [...] Read more.
This review covers the progress of nanomaterial-modified electrodes for enzymatic and non-enzymatic glucose biosensors. Fundamental insights into glucose biosensor components and the crucial factors controlling the electrochemical performance of glucose biosensors are discussed in detail. The metal, metal oxide, and hybrid/composite nanomaterial fabrication strategies for the modification of electrodes, mechanism of detection, and significance of the nanomaterials toward the electrochemical performance of enzymatic and non-enzymatic glucose biosensors are compared and comprehensively reviewed. This review aims to provide readers with an overview and underlying concept of producing a reliable, stable, cost-effective, and excellent electrochemical performance of a glucose biosensor. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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25 pages, 5770 KiB  
Review
Nano-Engineered Surface Comprising Metallic Dendrites for Biomolecular Analysis in Clinical Perspective
by Rohini Kumari, Daphika S. Dkhar, Supratim Mahapatra, Divya, Surinder P. Singh and Pranjal Chandra
Biosensors 2022, 12(12), 1062; https://doi.org/10.3390/bios12121062 - 22 Nov 2022
Cited by 6 | Viewed by 1616
Abstract
Metallic dendrites, a class of three-dimensional nanostructured materials, have drawn a lot of interests in the recent years because of their interesting hierarchical structures and distinctive features. They are a hierarchical self-assembled array of primary, secondary, and terminal branches with a plethora of [...] Read more.
Metallic dendrites, a class of three-dimensional nanostructured materials, have drawn a lot of interests in the recent years because of their interesting hierarchical structures and distinctive features. They are a hierarchical self-assembled array of primary, secondary, and terminal branches with a plethora of pointed ends, ridges, and edges. These features provide them with larger active surface areas. Due to their enormous active areas, the catalytic activity and conductivity of these nanostructures are higher as compared to other nanomaterials; therefore, they are increasingly used in the fabrication of sensors. This review begins with the properties and various synthetic approaches of nanodendrites. The primary goal of this review is to summarize various nanodendrites-engineered biosensors for monitoring of small molecules, macromolecules, metal ions, and cells in a wide variety of real matrices. Finally, to enlighten future research, the limitations and future potential of these newly discovered materials are discussed. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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20 pages, 5160 KiB  
Review
Recent Advances in Single-Molecule Sensors Based on STM Break Junction Measurements
by Shan-Ling Lv, Cong Zeng, Zhou Yu, Ju-Fang Zheng, Ya-Hao Wang, Yong Shao and Xiao-Shun Zhou
Biosensors 2022, 12(8), 565; https://doi.org/10.3390/bios12080565 - 26 Jul 2022
Cited by 13 | Viewed by 3600
Abstract
Single-molecule recognition and detection with the highest resolution measurement has been one of the ultimate goals in science and engineering. Break junction techniques, originally developed to measure single-molecule conductance, recently have also been proven to have the capacity for the label-free exploration of [...] Read more.
Single-molecule recognition and detection with the highest resolution measurement has been one of the ultimate goals in science and engineering. Break junction techniques, originally developed to measure single-molecule conductance, recently have also been proven to have the capacity for the label-free exploration of single-molecule physics and chemistry, which paves a new way for single-molecule detection with high temporal resolution. In this review, we outline the primary advances and potential of the STM break junction technique for qualitative identification and quantitative detection at a single-molecule level. The principles of operation of these single-molecule electrical sensing mainly in three regimes, ion, environmental pH and genetic material detection, are summarized. It clearly proves that the single-molecule electrical measurements with break junction techniques show a promising perspective for designing a simple, label-free and nondestructive electrical sensor with ultrahigh sensitivity and excellent selectivity. Full article
(This article belongs to the Special Issue Construction of Biosensors Using Nano- and Microtechnology)
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