Field Of Biosensors Research Articles

Recent Progress in Transition Metal Dichalcogenides for Electrochemical Biomolecular Detection.

Advances in the field of nanobiotechnology are largely due to discoveries in the field of materials. Recent developments in the field of electrochemical biosensors based on transition metal nanomaterials as transducer elements have been beneficial as they possess various functionalities that increase surface area and provide well-defined active sites to accommodate elements for rapid detection of biomolecules. In recent years, transition metal dichalcogenides (TMDs) have become the focus of interest in various applications due to their considerable physical, chemical, electronic, and optical properties. It is worth noting that their unique properties can be modulated by defect engineering and morphology control. The resulting multifunctional TMD surfaces have been explored as potential capture probes for the rapid and selective detection of biomolecules. In this review, our primary focus is to delve into the synthesis, properties, design, and development of electrochemical biosensors that are based on transition metal dichalcogenides (TMDs) for the detection of biomolecules. We aim to explore the potential of TMD-based electrochemical biosensors, identify the challenges that need to be overcome, and highlight the opportunities for further future development.

Aptamer-Based Optical and Electrochemical Sensors: A Review

There is a pressing need to identify recent directions in the field of aptamer-based sensing. DNA aptamers that are synthetically generated by in vitro selection mechanisms using the SELEX technique are single-stranded oligonucleotides which are selected to bind to a target with favorable sensitivity and selectivity. These aptamers have attracted significant attention due to their high binding affinity and ability to be easily engineered and provide various detection modes in what are known as aptasensors. Our aim is to focus on specialized detection strategies that have gained less attention but are of vital importance, such as optical detection in live cells, fluorescence polarization sensing, multi-analyte detection, colorimetric bioassays, wavelength shifting, and electrochemical-based detection. This will provide us with a perspective to facilitate developments in aptasensor technology for various targets, promising a bright future for biological receptors in the field of biosensing.

Nanozyme-Enhanced Electrochemical Biosensors: Mechanisms and Applications.

Nanozymes, as innovative materials, have demonstrated remarkable potential in the field of electrochemical biosensors. This article provides an overview of the mechanisms and extensive practical applications of nanozymes in electrochemical biosensors. First, the definition and characteristics of nanozymes are introduced, emphasizing their significant role in constructing efficient sensors. Subsequently, several common categories of nanozyme materials are delved into, including metal-based, carbon-based, metal-organic framework, and layered double hydroxide nanostructures, discussing their applications in electrochemical biosensors. Regarding their mechanisms, two key roles of nanozymes are particularly focused in electrochemical biosensors: selective enhancement and signal amplification, which crucially support the enhancement of sensor performance. In terms of practical applications, the widespread use of nanozyme-based electrochemical biosensors are showcased in various domains. From detecting biomolecules, pollutants, nucleic acids, proteins, to cells, providing robust means for high-sensitivity detection. Furthermore, insights into the future development of nanozyme-based electrochemical biosensors is provided, encompassing improvements and optimizations of nanozyme materials, innovative sensor design and integration, and the expansion of application fields through interdisciplinary collaboration. In conclusion, this article systematically presents the mechanisms and applications of nanozymes in electrochemical biosensors, offering valuable references and prospects for research and development in this field.

Metal-organic Skeleton (MOF) Composite based Using Electrochemical Immunobiosensor to Detect the Important Tumor Marker of Breast Cancer Glycotype Antigen 15-3

Breast cancer is one of the biggest threats to women's life and health in the world, and the mortality rate has reached the second highest in the world. With the development of metal organic skeleton (MOF) and the advantages of the composite in the field of electrochemistry and biosensing, various metal organic skeleton composites have been widely used in electrochemical biosensors. Thus, electrochemical biosensors have received extensive attention and research in the field of rapid breast cancer detection. This article mainly introduces the detection of sugar-type important tumor marker antigen 15-3, and electrochemical immunobiosensor Excellent performance in breast cancer detection and promising prospects for its application.

Nanostructure Tuning of Gold Nanoparticles Films via Click Sintering.

Colloidal metal nanoparticles dispersions are commonly used to create functional printed electronic devices and they typically require time-, energy- and equipment-consuming post-treatments to improve their electrical and mechanical properties. Traditional methods, e.g. thermal, UV/IR, and microwave treatments, limit the substrate options and may require expensive equipment, not available in all the laboratories. Moreover, these processes also cause the collapse of the film (nano)pores and interstices, limiting or impeding its nanostructuration. Finding a simple approach to obtain complex nanostructured materials with minimal post-treatments remains a challenge. In this study, a new sintering method for gold nanoparticle inks that called as "click sintering" has been reported. The method uses a catalytic reaction to enhance and tune the nanostructuration of the film while sintering the metallic nanoparticles, without requiring any cumbersome post-treatment. This results in a conductive and electroactive nanoporous thin film, whose properties can be tuned by the conditions of the reaction, i.e., concentration of the reagent and time. Therefore, this study presents a novel and innovative one-step approach to simultaneously sinter gold nanoparticles films and create functional nanostructures, directly and easily, introducing a new concept of real-time treatment with possible applications in the fields of flexible electronics, biosensing, energy, and catalysis.

Sensitivity enhancement of the LSPR-based tapered optical fiber biosensor by variation of nanoparticle arrangement

A tapered optical fiber sensor with four arrangements of gold nanoparticles (Au NPs) on its waist is simulated and the fiber transmittance by changing the analyte refractive index (RI) is obtained. The method is a combination of the finite-difference time-domain method and the finite element method. The effect of NPs on top of each other and dimers is investigated, which is the first step in studying the aggregation of NPs in the cluster NP model. In addition, the effects of fiber diameter, NP diameter, and fiber length are examined. It is shown that by variation of NP arrangement, the amplitude sensitivity increases from 1.5 per refractive index unit (RIU−1) to 4.53RIU−1 and the wavelength sensitivity increases from 58.24 to 116.74 nm/RIU. The dimensions of the structures and the ranges of analyte RIs are in the field of practical biosensors, to be close to reality and to be effective in diagnosing diseases.

Highly sensitive detection for xanthine by combining single-band red up-conversion nanoparticles and cycle signal amplification strategy based on internal filtration effect

Up-conversion nanoparticles (UCNPs), especially single-band bright red UCNPs, have better penetration of biological tissues, absorb less lost energy, and have higher sensitivity and accuracy in the determination of actual biological samples in the field of biosensing. Here, a novel colorimetric and fluorescent dual-channel method based upon an internal filtration effect (IFE) quenching mechanism was proposed for the quantitative analysis of xanthine (XA) by using red UCNPs as fluorescence indicator and 3,3′,5,5′ -tetramethylbenzidine (TMB) as chromogenic substrate. The sensitivity of the detection system was also enhanced by a cycle signal amplification strategy based on the Fenton reaction. Under the best conditions, the detection limits of XA by fluorescent and colorimetric methods were 0.58 μM and 1.19 μM, respectively. The developed method was applied to the detection of XA in actual serum samples, and the recoveries of the spiked samples by fluorescent and colorimetric methods were in the range of 96.3–104.3 % and 94.3–105.4 %, respectively. In addition, the commercial ELISA method was used to verify the application of the proposed method and the test results of XA were close to those obtained by fluorescent and colorimetric methods, indicating that the accuracy of the developed nanosensing system was acceptable.

Tailoring Efficient Fluorogenic Tactic for Ultrasensitive Detection of Dopamine in Urine and Rat Brain through Real-Time and In Situ Formation of High-Performance Fluorophore.

Owing to the predominance of dopamine (DA) in controlling mental health, planning an innovative method for DA detection with simplicity and high efficacy is conducive to the assessment of neurological disorders. Herein, an efficient fluorogenic tactic has been elaborated for ultrasensitive detection of DA with remarkably enhanced turn-on response. Utilizing a twisted intramolecular charge-transfer (TICT)-suppressing strategy, a highly emissive azocine derivative 11-hydroxy-2,3,6,7,11,12,13,14-octahydro-1H,5H,10H-11,14a-methanoazocino[5',4':4,5]furo[2,3-f]pyrido[3,2,1-ij]quinolin-10-one (J-Aza) is generated via a one-step reaction between DA and 8-hydroxyjulolidine. It is marvelous that J-Aza not only possesses ideal fluorescence quantum yield (ΦF) as high as 0.956 but also exhibits bathochromic shifted fluorescence (green emissive) and stronger anti-photobleaching capacity superior to traditional azocine-derived 1,2,3,4-tetrahydro-5H-4,11a-methanobenzofuro[2,3-d]azocin-5-one (Aza) with moderate ΦF, blue fluorescence, and poor photostability. By confining the TICT process, the detection limit to DA can be reduced to 80 pM, which is competitive in contrast to previously reported fluorescence methods. Encouraged by the instant response (within 90 s), wide linear range (0.1-500 nM), great selectivity, and excellent sensitivity, this fluorogenic method has been used for the real-time measurement of DA contents in practical urine samples with satisfactory results. Furthermore, the cerebral DA level in the reserpine-induced depression rat model has also been evaluated by our designed method, demonstrating its potent analytical applicability in the biosensing field.

Facile Fabrication of Wood-Derived Porous Fe3C/Nitrogen-Doped Carbon Membrane for Colorimetric Sensing of Ascorbic Acid.

Fe3C nanoparticles hold promise as catalysts and nanozymes, but their low activity and complex preparation have hindered their use. Herein, this study presents a synthetic alternative toward efficient, durable, and recyclable, Fe3C-nanoparticle-encapsulated nitrogen-doped hierarchically porous carbon membranes (Fe3C/N-C). By employing a simple one-step synthetic method, we utilized wood as a renewable and environmentally friendly carbon precursor, coupled with poly(ionic liquids) as a nitrogen and iron source. This innovative strategy offers sustainable, high-performance catalysts with improved stability and reusability. The Fe3C/N-C exhibits an outstanding peroxidase-like catalytic activity toward the oxidation of 3,3',5,5'-tetramethylbenzidine in the presence of hydrogen peroxide, which stems from well-dispersed, small Fe3C nanoparticles jointly with the structurally unique micro-/macroporous N-C membrane. Owing to the remarkable catalytic activity for mimicking peroxidase, an efficient and sensitive colorimetric method for detecting ascorbic acid over a broad concentration range with a low limit of detection (~2.64 µM), as well as superior selectivity, and anti-interference capability has been developed. This study offers a widely adaptable and sustainable way to synthesize an Fe3C/N-C membrane as an easy-to-handle, convenient, and recoverable biomimetic enzyme with excellent catalytic performance, providing a convenient and sensitive colorimetric technique for potential applications in medicine, biosensing, and environmental fields.

Design of a highly sensitive cascaded rectangular ring resonator embedded with gold nanorods and gratings for multipurpose application

This study introduces a sensor consisting of a metal-insulator-metal (MIM) structure, having an integration of gold nanorods and gratings, to perform various functions including sensing refractive index, detecting blood components, monitoring temperature, and measuring magnetic fields. The sensor's spectral properties are studied analytically in the MIR region implementing finite element method. Furthermore, the potential in the RI sensing is extensively examined by modulating the geometrical parameters, ultimately establishing a direct relationship with the transmittance profile. Following computational experiments, the best possible configuration exhibits the maximum sensitivity of 6118.685 nm/RIU. This research shows the biosensing applications by the detection of near-infrared and visible blood components such RBC, Hb, WBC, plasma, and water with a high sensitivity of 3185.05 nm/RIU. Moreover, ethanol is employed to evaluate the proffered sensor's temperature sensing feature and a maximum sensitivity 1.18 nm/°C was attained. Furthermore, this sensor can be used for magnetic field detection as it shows a high magnetic field sensitivity of 354.66 pm/Oe. The structural model is simple. Besides, this design has the potential to serve as a substitute for sensors that rely on silver. It is chemically stable and performs well in refractive index measurement, biosensing, temperature sensing and magnetic field detection.

Electrochemical Analysis of Clinical Samples – A Path to Translational Research

Precise diagnostics of cancer or other diseases is crucial when selecting proper treatment. Personalized medicine puts high demands on the accuracy of nucleic acid biomarkers analysis, where subtle differences at the nucleotide level are often involved. Isothermal amplification techniques offer new possibilities of DNA and RNA amplification without using PCR, and their combination with electrochemistry provide a promising fast and cost-effective alternative diagnostic tool. Although electrochemical biosensors are still insufficiently applied to clinical material, thus hindering their development, recent advancements show great promise in translational research. Banks of biological material (biobanks) are specialized workplaces focused on the long-term preservation and processing of clinical material and offer a wide range of expert services, primarily for research purposes, in particular the provision of biological samples and associated pseudonymized data. Their involvement in the field of electrochemical biosensors can facilitate application of electrochemical methods into clinical laboratories and expand the portfolio of currently used diagnostic methods.

0D, 1D, and 2D magnetic nanostructures: Classification and their applications in modern biosensors

Magnetic nanomaterials have emerged as versatile platforms that offer unique advantages in various biomedical applications. With the incorporation of magnetic nanomaterials, which include zero-dimensional (0D), one-dimensional (1D), and two-dimensional (2D) variants, the field of biosensors is rapidly expanding. This review examines the properties, role, and functionalization of 0D, 1D, and 2D magnetic nanomaterials and highlights their distinct advantages in improving the selectivity, limit of detection (LOD), and specificity in biosensing applications. This article also emphasizes magnetic properties and magnetism-based approaches utilized in the arena of magnetic nanomaterials-based biosensors. In addition, the review covers the recent advances and developments in the integration of magnetic nanomaterials (0D, 1D, and 2D) with various electrochemical, optical, and magnetic-based biosensing techniques for the detection of various biomolecules, pathogens, and diagnosis of numerous diseases.

Microfluidics on lensless, semiconductor optical image sensors: challenges and opportunities for democratization of biosensing at the micro-and nano-scale

Abstract Optical image sensors are 2D arrays of pixels that integrate semiconductor photodiodes and field effect transistors for efficient photon conversion and processing of generated electrons. With technological advancements and subsequent democratization of these sensors, opportunities for integration with microfluidics devices are currently explored. 2D pixel arrays of such optical image sensors can reach dimensions larger than one centimeter with a sub-micrometer pixel size, for high spatial resolution lensless imaging with large field of view, a feat that cannot be achieved with lens-based optical microscopy. Moreover, with advancements in fabrication processes, the field of microfluidics has evolved to develop microfluidic devices with an overall size below one centimeter and individual components of sub-micrometer size, such that they can now be implemented onto optical image sensors. The convergence of these fields is discussed in this article, where we review fundamental principles, opportunities, challenges, and outlook for integration, with focus on contact-mode imaging configuration. Most recent developments and applications of microfluidic lensless contact-based imaging to the field of biosensors, in particular those related to the potential for point of need applications, are also discussed.

Current Understanding and Prospects of Silver Nanoparticles-Based Biosensor

Due to their distinctive optical potential, controlled plasmonic features, control over size and shape, and ability to manipulate their localized surface plasmon resonance (LSPR) and their response to their surroundings, silver nanoparticle attracts special attention in the fields of the biosensor. Silver (Ag) is an appealing tool in many domains, including diagnosis, medicine delivery, environment, electronics, and as an antibacterial agent. Ag nanoparticle applications are ubiquitous today in the fields of biosensors. Numerous studies have demonstrated the effectiveness of using Ag nanoparticles to improve the specific detection of clinical indicators. The development of nanotechnology has greatly benefited the field of biosensors since nanomaterials have a high surface-to-volume ratio that enables them to operate with greater sensitivity and effectiveness. Utilizing interdisciplinary study in biology, chemistry, and material science, recent advancements in nanotechnology encouraged the manufacture of nanomaterials in a variety of shapes and sizes. In the context of disease diagnosis, this review highlighted the use of Ag nanoparticles in biosensors to detect small molecules to bigger entire cells. This paper also discusses how to make a glucose biosensor more sensitive. It describes how the detection performance of biomolecules including DNA, protein, tiny molecules, and complete cells can be improved. For future applications in the field of diagnosis, this review helps in developing an overall understanding of the clinical importance of Ag nanoparticles. These biosensors can be implemented in the field of diagnosis to speed up the response time.

Gold nanorods and tungsten disulfide nanocomposite modified electrode for hemoglobin electrochemical biosensing of trichloroacetic acid and nitrite

In this paper, gold nanorods (AuNRs) and tungsten disulfide (WS2) nanocomposite was prepared and modified on the carbon ionic liquid electrode (CILE) surface. Hemoglobin (Hb) was further immobilized on the electrode surface to fabricate a novel modified electrode (Nafion/Hb/AuNRs-WS2/CILE), which exhibited high conductivity and good biocompatibility. The electrochemical behaviors of Hb on the modified electrode were investigated with the appearance of a pair of well-shaped redox peaks, which may be ascribed to direct electron transfer of Hb Fe(III)/Fe(II) redox center. Besides, Nafion/Hb/AuNRs-WS2/CILE showed excellent electrocatalytic activity to the reduction of trichloroacetic acid and nitrite with a wide linear range, and the low detection limit could be obtained as 1.0 mmol/L and 0.33 mmol/L, which extended the application of AuNRs-WS2 nanocomposite in the field of bioelectrochemistry and electrochemical biosensors.

Characterization of a High-performance PCF-SPR Sensor for Biomedical Applications

Background: Surface plasmon resonance (SPR) based fibre optic sensors are becoming increasingly popular in biomedical applications. However, the sensor performance is degraded because of low sensitivity with inadequate detection accuracy and figure of merit. Objectives: The first objective of this study is to design a D-shaped photonic crystal fibre (PCF) using COMSOL multiphysics. The second objective is to enhance the performance of the designed sensor in terms of sensitivity and detection accuracy using single and dual metal layer structures. In addition, the performance of the proposed sensor is compared with the existing one. Methods: In this study, the performance of the PCF-SPR sensor is improved using a D-shaped photonic crystal fibre (PCF) and two metals as grating layers. The work in this paper is divided into two parts. In the first part, the gold metal layer with optimized thickness is used to achieve good sensitivity. In the second part, the combination of gold and silver dual metal layers with optimized thickness is used to achieve good detection accuracy. Moreover, the performance of the proposed sensor is compared to other published D-shaped PCF sensors. Results: The proposed D-shaped PCF-SPR sensor is designed and simulated using COMSOL multiphysics. The results in terms of sensitivity (S) and detection accuracy (DA) are obtained using a single metal layer and dual metal layers with optimum thickness. Moreover, the transmission coefficient and loss curve have been calculated using different refractive indices of the material. In addition, the simulation results are validated for cancer detection using the proposed sensor. Conclusion: An improvement of the D-shaped PCF sensor for cancer detection is presented in terms of S and DA using single or dual metal layer structures and COMSOL multiphysics. In a single metal layer structure, only gold is used as a grating layer, and the thickness of the grating layer is optimized for achieving high sensitivity. Similarly, a combination of gold and silver is used as the grating layer in the dual metal layer structure for achieving a high DA. Moreover, the obtained results of the proposed PCFSPR sensor are compared with the published results and found that the proposed sensor can be used with a high degree of S and DA for biomedical applications and also can be used in the bio-sensing field.

Bio-Convective Hartmann Flow of Couple Stress Hybrid Nanofluid Between Two Dilating Parallel Walls with Heat and Mass Transfer

The study of bio-convective flow of hybrid nanofluid attracted many researchers because of tremendous applications in the fields of biofuel biotechnology, enzyme-based biosensors and biomedical science. The present work addresses a comparative study of CuO/Al2O3-water and CuO-water nanoparticles on heat and mass transfer characteristics of the squeezing flow of MHD couple stress fluid between two parallel plates by suspending motile micro-organisms. An approximated numerical technique (Shooting method along with Runge-Kutta 4th order scheme) have been employed to analyse the system of coupled nonlinear ordinary differential equations. The above numerical investigations were carried out for various governing parameters such as couple stress parameter, Hartmann number, bioconvection Peclet number, squeezing parameter etc. The effects of these physical parameters are illustrated graphically over velocity components, temperature distribution, diffusion of concentration and density of motile microorganisms. In addition to this the numerical values of skin friction, the local Nusselt number and local Sherwood number are tabulated at the upper plate for CuO-water and CuO–Al2O3-water at the expanding and squeezing cases. The numerical results for temperature profiles are in good consistency with earlier research.

Sensitive detection of Escherichia coli in diverse foodstuffs by electrochemical aptasensor based on 2D porphyrin-based COF.

The two-dimensional porphyrin-based covalent organic framework (denoted by Tph-TDC-COF) was used as the sensitive layerto build an aptamer-based electrochemical sensor for the detection of Escherichia coli (E.coli). Tph-TDC-COF produced with 5,10,15,20-tetrakis(4-aminophenyl)-21H, 23H-porphine (Tph) and [2,2'-bithiophene]-2,5'-dicarbaldehyde (TDC) as building blocks exhibited a highly conjugated structure, outstanding conductivity, large specific surface area, and strong bioaffinity towards aptamers. The adoption of Tph-TDC-COF-modified electrode resulted in improved sensing performance and increased anchoring affinity toward the E.coli-targeted aptamer. Under optimal conditions, the Tph-TDC-COF-based electrochemical aptasensor demonstrated an extremely low detection limit of 0.17CFUmL-1 for E.coli detection within a linear range of 10 to 1 × 108CFUmL-1, accompanied by good stability, excellent reproducibility and regeneration ability, and wide practical applications. The current electrochemical aptasensing technique has the potential to be extended to detect different foodborne bacteria using specific aptamer, therefore widening the application of COFs in biosensing and food safety fields.

Plasmonic Nanostructure Biosensors: A Review.

Plasmonic nanostructure biosensors based on metal are a powerful tool in the biosensing field. Surface plasmon resonance (SPR) can be classified into localized surface plasmon resonance (LSPR) and propagating surface plasmon polariton (PSPP), based on the transmission mode. Initially, the physical principles of LSPR and PSPP are elaborated. In what follows, the recent development of the biosensors related to SPR principle is summarized. For clarity, they are categorized into three groups according to the sensing principle: (i) inherent resonance-based biosensors, which are sensitive to the refractive index changes of the surroundings; (ii) plasmon nanoruler biosensors in which the distances of the nanostructure can be changed by biomolecules at the nanoscale; and (iii) surface-enhanced Raman scattering biosensors in which the nanostructure serves as an amplifier for Raman scattering signals. Moreover, the advanced application of single-molecule detection is discussed in terms of metal nanoparticle and nanopore structures. The review concludes by providing perspectives on the future development of plasmonic nanostructure biosensors.

Noise Spectroscopy Analysis of Ion Behavior in Liquid Gate‐All‐Around Silicon Nanowire Field‐Effect Transistor Biosensors

AbstractThe transport and noise properties of fabricated, high‐performance, gate‐all‐around silicon liquid‐gated nanowire field‐effect transistor devices are investigated in different concentrations of MgCl2 solutions. The critical concentration of MgCl2 solution for charge inversion at the solid‐liquid interface is verified using noise spectroscopy and confirmed using the capacitance‐voltage measurement technique. In this study, it is found that the Hooge parameter (αH) and the equivalent input noise (SU) can effectively reflect the ion behavior on the surface of the nanowire. Moreover, the noise curves for αH and SU indicate two turning points at concentrations of 10−4 and 10−1 m for a peak and a valley, respectively. The noise transformation is related to the behavior of ions near the solid‐liquid interface in solutions with different MgCl2 concentrations is revealed. The results show that noise spectroscopy is a powerful method for monitoring charge dynamic processes in the research field of biosensors.