Carbon Nanomaterials-Based Screen-Printed Electrodes for Sensing Applications

Chemical Sensors and Biosensors for Point-of-Care Testing of Pets: Opportunities for Individualized Diagnostics of Companion Animals

Point-of-care testing (POCT) is recognized as one of the most disruptive medical technologies for rapid and decentralized diagnostics. Successful commercial examples include portable glucose meters, pregnancy tests, and COVID-19 self-tests. However, compared to advancements in human healthcare, POCT technologies for companion animals (pets) remain significantly underdeveloped. This Review explores the latest advancements in pet POCT and examines the challenges and opportunities in the field for individualized diagnostics of cats and dogs. The most frequent diseases and their respective biomarkers in blood, urine, and saliva are discussed. We examine key strategies for developing the next-generation POCT devices by harnessing the potential of selective (bio)receptors and high-performing transducers such as lateral flow tests and electrochemical (bio)sensors. We also present the most recent research initiatives and the successful commercial pet POCT technologies. We discuss future trends in the field, such the role of biomarker discovery and development of wearable, implantable, and breath sensors. We believe that advancing pet POCT technologies benefits not only animals but also humans and the environment, supporting the One Health approach.

Screen-Printing vs Additive Manufacturing Approaches: Recent Aspects and Trends Involving the Fabrication of Electrochemical Sensors

A few decades ago, the technological boom revolutionized access to information, ushering in a new era of research possibilities. Electrochemical devices have recently emerged as a key scientific advancement utilizing electrochemistry principles to detect various chemical species. These versatile electrodes find applications in diverse fields, such as healthcare diagnostics and environmental monitoring. Modern designs have given rise to innovative manufacturing protocols, including screen and additive printing methods, for creating sophisticated 2D and 3D electrochemical devices. This perspective provides a comprehensive overview of the screen-printing and additive-printing protocols for constructing electrochemical devices. It is also informed that screen-printed sensors offer cost-effectiveness and ease of fabrication, although they may pose challenges due to the use of toxic volatile inks and limited design flexibility. On the other hand, additive manufacturing, especially the fused filament fabrication (or fused deposition modeling) strategies, allows for intricate three-dimensional sensor designs and rapid prototyping of customized equipment. However, the post-treatment processes and material selection can affect production costs. Despite their unique advantages and limitations, both printing techniques show promise for various applications, driving innovation in the field toward more advanced sensor designs. Finally, these advancements pave the way for improved sensor performance and expand possibilities for academic, environmental, and industrial applications. The future is full of exciting opportunities for state-of-the-art sensor technologies that will further improve our ability to detect and determine various substances in a wide range of environments as researchers continue to explore the many possibilities of electrochemical devices.

Electrochemical and Optical Carbon Dots and Glassy Carbon Biosensors: A Review on Their Development and Applications in Early Cancer Detection

Cancer remains one of the leading causes of mortality worldwide, making early detection a critical factor in improving patient outcomes and survival rates. Developing advanced biosensors is essential for achieving early detection and accurate cancer diagnosis. This review offers a comprehensive overview of the development and application of carbon dots (CDs) and glassy carbon (GC) biosensors for early cancer detection. It covers the synthesis of CDs and GC, electrode fabrication methods, and electrochemical and optical transduction principles. This review explores various biosensors, including enzymatic and non-enzymatic, and discusses key biomarkers relevant to cancer detection. It also examines characterization techniques for electrochemical and optical biosensors, such as electrochemical impedance spectroscopy, cyclic voltammetry, UV-VIS, and confocal microscopy. The findings highlight the advancements in biosensor performance, emphasizing improvements in sensitivity, selectivity, and stability, as well as underscoring the potential of integrating different transduction methods and characterization approaches to enhance early cancer detection.

A disposable ultrasensitive immunosensor based on MXene/NH2-CNT modified screen-printed electrode for the detection of ovarian cancer antigen CA125

Cancer antigen 125 (CA125) is the gold standard biomarker for clinical diagnosis of ovarian cancer, with a threshold value of 35 U/mL in serum. In this paper, a disposable ultrasensitive immunosensor based on Ti3C2Tx-MXene/amino-functionalized carbon nanotube (NH2-CNT) modified screen-printed carbon electrode (SPCE) was constructed for the detection of the ovarian cancer antigen CA125. By optimizing the mass ratio of Ti3C2Tx to NH2-CNT, Ti3C2Tx/NH2-CNT composite with excellent electrochemical properties was prepared, which is beneficial for amplifying the initial electrochemical signal. The positively charged NH2-CNT effectively alleviated the stacking problem of Ti3C2Tx, and its amino group also facilitated the covalent immobilization of the capture antibody. Meanwhile, chitosan (CS) with excellent film-forming ability was also used to successfully enhance the adsorption of electrode material, thus improving the stability of the sensor. In addition, CS could further enhance the current signal. The prepared immunosensor exhibited excellent performance in CA125 detection with a wide linear range from 1 mU/mL to 500 U/mL, and good selectivity, reproducibility and lomg-term stability. Furthermore, the immunosensor showed satisfactory results for the detection of CA125 in clinical serum samples, which is promising for the clinical screening, early diagnosis and prognostic examination of ovarian cancer.

Advanced chemically modified electrodes and platforms in food analysis and monitoring

Electrochemical sensors and electroanalytical techniques become emerging as effective and low-cost tools for rapid assessment of special parameters of the food quality. Chemically modified electrodes are developed to change properties and behaviour, particularly sensitivity and selectivity, of conventional electroanalytical sensors. Within this comprehensive review, novel trends in chemical modifiers material structure, electrodes construction and flow analysis platforms are described and evaluated. Numerous recent application examples for the detection of food specific analytes are presented in a form of table to stimulate further development in both, the basic research and commercial field.

A comprehensive review on advancements in sensors for air pollution applications

Air pollution, originating from both natural and human-made sources, presents significant threats to human health and the environment. This review explores the latest technological advancements in air quality sensors focusing on their applications in monitoring a wide range of pollution sources from volcanic eruptions and wildfires to industrial emissions, transportation, agricultural activities and indoor air quality. The review categorizes these sources and examines the operational principles, system architectures, and effectiveness of various air quality monitoring instruments including low-cost sensors, gas analyzers, weather stations, passive sampling devices and remote sensing technologies such as satellite and LiDAR. Key insights include the rapid evolution of sensor technology driven by the need for more accurate, real-time monitoring solutions that are both cost-effective and widely accessible. Despite significant advancements, challenges such as sensor calibration, standardization, and data integration remain critical for ensuring reliable air quality assessments. The manuscript concludes by emphasizing the need for continued innovation and the integration of advanced sensor technologies with regulatory frameworks to enhance environmental management and public health protection.

Decorated Electrode Surfaces with Nanostructures and Metal-Organic Frameworks as Transducers for Sensing

In this study, several materials are presented as modifiers of the screen-printed carbon electrodes with the aim of developing new sensing platforms for the voltammetric analysis of drugs. Specifically, Clotiapine and Sulfamethoxazole were selected as models for antipsychotics and antibiotics, respectively. Different nanostructures were studied as modifiers, including both transition metals and carbon-based materials. Moreover, biochar and two metal-organic frameworks (MOFs) were tested as well. The NH2-MIL-125(Ti) MOF showed an 80% improvement in the analytical signal of Sulfamethoxazole, but it partially overlapped with an additional signal associated with the loss of the MOF ligand. For this reason, several immobilization strategies were tested, but none of them met the requirements for the development of a sensor for this analyte. Conversely, carbon nanotubes and the NH2-MIL-101(Fe) MOF were successfully applied for the analysis of Clotiapine in the medicine Etumine®, with RSD below 2% and relative errors that did not exceed 9% in any case, which demonstrates the precision and accuracy achieved with the tested modifications. Despite these promising results, it was not possible to lower the limits of detection and quantification, so in this sense further investigation must be performed to increase the sensitivity of the developed sensors.

Applications of chemically modified screen-printed electrodes in food analysis and quality monitoring: a review

Food analysis and food quality monitoring are vital aspects of the food industry, ensuring the safety and authenticity of various food products, from packaged goods to fast food. In this comprehensive review, we explore the applications of chemically modified Screen-Printed Electrodes (SPEs) in these critical domains. SPEs have become extremely useful devices for ensuring food safety and quality assessment because of their adaptability, affordability, and convenience of use. The Introduction opens the evaluation, that covers a wide spectrum of foods, encompassing packaged, junk food, and food quality concerns. This sets the stage for a detailed exploration of chemically modified SPEs, including their nature, types, utilization, and the advantages they offer in the context of food analysis. Subsequently, the review delves into the multitude applications of SPEs in food analysis, ranging from the detection of microorganisms such as bacteria and fungi, which are significant indicators of food spoilage and safety, to the identification of pesticide residues, food colorants, chemicals, toxins, and antibiotics. Furthermore, chemically modified SPEs have proven to be invaluable in the quantification of metal ions and vitamins in various food matrices, shedding light on nutritional content and quality.

DEMIGOD: A Low-Cost Microcontroller-Based Closed-Loop System Integrating Nanoengineered Sweat-Based Glucose Monitoring and Controlled Transdermal Nanoemulsion Release of Hypoglycemic Treatment with a Software Application for Noninvasive Personalized Diabetes Care

This study endeavored to design and develop an innovative closed-loop diagnostic and therapeutic system with the following objectives: (a) the noninvasive detection of glucose concentration in sweat utilizing nanonengineered screen-printed biosensors; (b) the management of measured data through a specialized computer system comprising both hardware and software components, thereby enabling the precise control of therapeutic responses via a patch-based nanomedicine delivery system. This initiative addresses the significant challenges inherent in the management of diabetes mellitus, including the imperative need for glucose-level monitoring to optimize glycemic control. Leveraging chronoamperometric results as a foundational dataset and the in vivo hypoglycemic activity of nanoemulsion formulations, this research underscores the efficacy and accuracy of glucose concentration estimation, decision-making mechanism responses, and transdermal hypoglycemic treatment effects, within the proposed system.

Self-powered molecularly imprinted photoelectrochemical sensor based on Ppy/QD/HOF heterojunction for the detection of bisphenol A

As an emerging porous material, hydrogen-bonded organic framework materials (HOFs) still pose application challenges. In this work, the designed type "I + II" heterojunction extracted hot electrons from HOFs using quantum dots (QDs) and polypyrrole (Ppy), improving the stability and photoelectrochemical performance of materials. In addition to serving as a potential well, electropolymerized Ppy was used as a recognition element for bisphenol A (BPA), and a novel self-powered molecularly imprinted photoelectrochemical (MIP-PEC) sensor was designed. The sensing platform showed a linear relationship from 1 × 10-10 to 1 × 10-7 mol∙L-1 and from 1 × 10-7 to 1 mol∙L-1 with an acceptable detection limit of 4.2 × 10-11 mol∙L-1. This is the first application of HOFs in constructing MIP-PEC sensors and a new attempt to improve the stability of HOFs for the application of porous crystal materials in the sensing field.

Nanoimprint Lithography for Next-Generation Carbon Nanotube-Based Devices

This research reports the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors, and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nanoimprint lithography (NIL), magnetron sputtering, and reactive etching techniques was studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over an alumina support layer on a Si/SiO2 substrate. The metal particles were deposited using direct current (DC) magnetron sputtering technique, with a particle ranging from 6 nm to 12 nm and density from 70 to 1000 particles/micron. The Alumina layer was deposited by radio frequency (RF) and reactive pulsed DC sputtering, and the effect of sputtering parameters on surface roughness was studied. The pattern was developed by thermal NIL using Si master-molds with PMMA and NRX1025 polymers as thermal resists. Catalyst patterns of lines, dots, and holes ranging from 70 nm to 500 nm were produced and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Vertically aligned CNTs were successfully grown on patterned catalyst and their quality was evaluated by SEM and micro-Raman. The results confirm that the new fabrication process has the ability to control the size and shape of CNT arrays with superior quality.

Electrochemical Nanosensor for the Simultaneous Determination of Anticancer Drugs Epirubicin and Topotecan Using UiO-66-NH2/GO Nanocomposite Modified Electrode

In this work, UiO-66-NH2/GO nanocomposite was prepared using a simple solvothermal technique, and its structure and morphology were characterized using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). An enhanced electrochemical sensor for the detection of epirubicin (EP) was proposed, which utilized a UiO-66-NH2/GO nanocomposite-modified screen-printed graphite electrode (UiO-66-NH2/GO/SPGE). The prepared UiO-66-NH2/GO nanocomposite improved the electrochemical performance of the SPGE towards the redox reaction of EP. Under optimized experimental conditions, this sensor demonstrates a remarkable limit of detection (LOD) of 0.003 µM and a linear dynamic range from 0.008 to 200.0 µM, providing a highly capable platform for sensing EP. Furthermore, the simultaneous electro-catalytic oxidation of EP and topotecan (TP) was investigated at the UiO-66-NH2/GO/SPGE surface utilizing differential pulse voltammetry (DPV). DPV measurements revealed the presence of two distinct oxidation peaks of EP and TP, with a peak potential separation of 200 mV. Finally, the UiO-66-NH2/GO/SPGE sensor was successfully utilized for the quantitative analysis of EP and TP in pharmaceutical injection, yielding highly satisfactory results.

A new strategy to build electrochemical enzymatic biosensors using a nanohybrid material based on carbon nanotubes and a rationally designed schiff base containing boronic acid

We report a nanohybrid material obtained by non-covalent functionalization of multi-walled carbon nanotubes (MWCNTs) with the new ligand (((1E,1'E)-(naphthalene-2,3-diylbis(azaneylylidene))bis(methaneylylidenedene)) bis(4-hydroxy-3,1-phenylene))diboronic acid (SB-dBA), rationally designed to mimic some recognition properties of biomolecules like concanavalin A, for the development of electrochemical biosensors based on the use of glycobiomolecules as biorecognition element. We present, as a proof-of-concept, a hydrogen peroxide biosensor obtained by anchoring horseradish peroxidase (HRP) at a glassy carbon electrode (GCE) modified with the nanohybrid prepared by sonication of 2.0 mg mL-1 MWCNTs and 0.50 mg mL-1 SB-dBA in N,N-dimethyl formamide (DMF) for 30 min. The hydrogen peroxide biosensing was performed at -0.050 V in the presence of 5.0 × 10-4 M hydroquinone. The analytical characteristics of the resulting biosensor are the following: linear range between 0.175 μM and 6.12 μM, detection limit of 58 nM, and reproducibility of 2.0 % using the same nanohybrid (6 biosensors), and 9.0 % using three different nanohybrids. The sensor was successfully used to quantify hydrogen peroxide in enriched milk and human blood serum samples and in a commercial disinfector.

Effect of Aspect Ratio of a Gold-Nanorod-Modified Screen-Printed Carbon Electrode for Carbaryl Detection in Three Different Samples of Vegetables

In this study, three different sizes of gold nanorods (AuNRs) were synthesized using the seed-growth method by adding various volumes of AgNO3 as 400, 600, and 800 μL into the growth solution of gold nanoparticles. Three different sizes of AuNRs were then characterized using UV-vis spectroscopy, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) patterns, and atomic force microscopy (AFM) to investigate the surface morphology, topography, and aspect ratios of each synthesized AuNR. The aspect ratios from the histogram of size distributions of three AuNRs as 2.21, 2.53, and 2.85 can be calculated corresponding to the addition of AgNO3 volumes of 400, 600, and 800 μL. Moreover, each AuNR in three different aspect ratios was drop-cast onto the surface of a commercial screen-printed carbon electrode (SPCE) to obtain three different SPCE-modified AuNRs (SPCE-A400, SPCE-A600, and SPCE-A800, respectively). All SPCE-modified AuNRs were then evaluated for their electrochemical behavior using cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques and the highest electrochemical performance was shown as the order of magnitude of SPCE-A400 > SPCE-A600/SPCE-A800. The reason for the highest electrocatalytic activity of SPCE-A400 might be due to the smallest particle size and uniform distribution of AuNRs ∼ 2.2, which enhanced the charge transfer, thus providing the highest electroactive surface area (0.6685 cm2) compared to other electrodes. These results also confirm that the sensing mechanism for all SPCE-modified AuNRs is controlled by diffusion phenomena. In addition, the optimum pH was obtained as 4 for carbaryl detection for all SPCE-modified AuNRs with the highest current shown by SPCE-A400. Furthermore, SPCE-A400 has the highest fundamental parameters (surface coverage, catalytic rate constant, electron transfer rate constant, and adsorption capacity) for carbaryl detection, which were investigated using cyclic voltammetry and chronoamperometric techniques. The electroanalytical performances of all SPCE-modified AuNRs for carbaryl detection were also investigated with SPCE-A400 displaying the best performance among other electrodes in terms of its linearity (0.2-100 μM), limit of detection (LOD) ∼ 0.07 μM, and limit of quantification (LOQ) ∼ 0.2 μM. All SPCE-modified AuNRs were also subsequently evaluated for their stability, reproducibility, and selectivity in the presence of interfering species such as NaNO2, NH4NO3, Zn(CH3CO2)2, FeSO4, diazinon, and glucose and show reliable results as depicted from %RSD values less than 3%. At last, all SPCE-modified AuNRs have been employed for carbaryl detection using a standard addition technique in three different samples of vegetables (cabbage, cucumber, and Chinese cabbage) with its results (%recovery ≈ 100%) within the acceptable analytical range. In conclusion, this work demonstrates the great potential of a disposable device based on an AuNR-modified SPCE for rapid detection and high sensitivity in monitoring the concentration of carbaryl as a residual pesticide in vegetable samples.

A non-contact porous composite fiber paper-based humidity sensor for wearable breathing and skin humidity monitoring

Flexible sensors capable of continuously monitoring surface moisture and respiratory status play a crucial role in human health monitoring.

Simultaneous recognition of dopamine and uric acid in real samples through highly sensitive new electrode fabricated using ZnO/carbon quantum dots: bio-imaging and theoretical studies

Dopamine (DA) and uric acid (UA), which are vital components in human metabolism, cause several health problems if they are present in altered concentrations; thus, the determination of DA and UA is essential in real samples using selective sensors. In the present study, graphite carbon paste electrodes (CPE) were fabricated using ZnO/carbon quantum dots (ZnO/CQDs) and employed as electrochemical sensors for the detection of DA and UA. These electrodes were fully characterized via different analytical techniques (XRD, SEM, TEM, XPS, and EDS). The electrochemical responses from the modified electrodes were evaluated using cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy. The results showed that the present electrode has exhibited high sensitivity towards DA, recognizing even at low concentrations (0.12 μM), and no inference was observed in the presence of UA. The ZnO/CQD electrode was applied for the simultaneous detection of co-existing DA and UA in real human urine samples and the peak potential separation between DA and UA was found to be greatly associated with the synergistic effect originated from ZnO and CQDs. The limit of detection (LOD) of the electrode was analyzed, and compared with other commercially available electrodes. Thus, the ZnO/CQD electrode was used to detect DA and UA in real samples, such as Saccharomyces cerevisiae cells.

Activated Screen-Printed Boron-Doped Diamond Electrode for Rapid and Highly Sensitive Determination of Curcumin in Food Products

Due to a great interest in the beneficial properties of polyphenolic antioxidant curcumin (CCM), sensitive and accurate methods for determining CCM are needed. The purpose of our research was to develop a very simple, fast, and sensitive differential pulse adsorptive stripping voltammetric (DPAdSV) procedure using an electrochemically activated screen-printed boron-doped diamond electrode (aSPBDDE) for the determination of CCM. The activation of the SPBDDE was accomplished in a solution of 0.1 mol/L NaOH by performing five cyclic voltammetric scans in the range of 0-2 V, at ν of 100 mV/s. The changes in surface morphology and the reduction of the charge transfer resistance due to the activation of the electrode resulted in the amplification of the CCM analytical signal on the aSPBDDE. As a result, an extremely sensitive measurement tool was formed, which under optimized conditions (0.025 mol/L PBS of pH = 2.6, Eacc of 0.3 V, tacc of 90 s, ΔEA of 100 mV, ν of 150 mV/s, and tm of 10 ms) allowed us to obtain a limit of detection (LOD) of 5.0 × 10-13 mol/L. The aSPBDDE has proven to be a highly effective tool for the direct determination of CCM in food samples with high accuracy and precision. The results are in agreement with those obtained using ultra-high-performance liquid chromatography coupled with mass spectrometry and electrospray ionization (UHPLC-ESI/MS).

Fabrications of the Flexible Non-Enzymatic Glucose Sensors Using Au-CuO-rGO and Au-CuO-rGO-MWCNTs Nanocomposites as Carriers

A flexible, non-enzymatic glucose sensor was developed and tested on a polyethylene terephthalate (PET) substrate. The sensor's design involved printing Ag (silver) as the electrode and utilizing mixtures of either gold-copper oxide-modified reduced graphene oxide (Au-CuO-rGO) or gold-copper oxide-modified reduced graphene oxide-multi-walled carbon nanotubes (Au-CuO-rGO-MWCNTs) as the carrier materials. A one-pot synthesis method was employed to create a nanocomposite material, consisting of Au-CuO-rGO mixtures, which was then printed onto pre-prepared flexible electrodes. The impact of different weight ratios of MWCNTs (0~75 wt%) as a substitute for rGO was also investigated on the sensing characteristics of Au-CuO-rGO-MWCNTs glucose sensors. The fabricated electrodes underwent various material analyses, and their sensing properties for glucose in a glucose solution were measured using linear sweep voltammetry (LSV). The LSV measurement results showed that increasing the proportion of MWCNTs improved the sensor's sensitivity for detecting low concentrations of glucose. However, it also led to a significant decrease in the upper detection limit for high-glucose concentrations. Remarkably, the research findings revealed that the electrode containing 60 wt% MWCNTs demonstrated excellent sensitivity and stability in detecting low concentrations of glucose. At the lowest concentration of 0.1 μM glucose, the nanocomposites with 75 wt% MWCNTs showed the highest oxidation peak current, approximately 5.9 μA. On the other hand, the electrode without addition of MWCNTs displayed the highest detection limit (approximately 1 mM) and an oxidation peak current of about 8.1 μA at 1 mM of glucose concentration.

Preparation, Modification, and Application of Biochar in the Printing Field: A Review

Biochar is a solid material enriched with carbon produced by the thermal transformation of organic raw materials under anoxic or anaerobic conditions. It not only has various environmental benefits including reducing greenhouse gas emissions, improving soil fertility, and sequestering atmospheric carbon, but also has the advantages of abundant precursors, low cost, and wide potential applications, thus gaining widespread attention. In recent years, researchers have been exploring new biomass precursors, improving and developing new preparation methods, and searching for more high-value and meaningful applications. Biochar has been extensively researched and utilized in many fields, and recently, it has also shown good industrial application prospects and potential application value in the printing field. In such a context, this article summarizes the typical preparation and modification methods of biochar, and also reviews its application in the printing field, to provide a reference for future work.

Newly Developed Electrochemiluminescence Based on Bipolar Electrochemistry for Multiplex Biosensing Applications: A Consolidated Review

Recently, there has been an upsurge in the extent to which electrochemiluminescence (ECL) working in synergy with bipolar electrochemistry (BPE) is being applied in simple biosensing devices, especially in a clinical setup. The key objective of this particular write-up is to present a consolidated review of ECL-BPE, providing a three-dimensional perspective incorporating its strengths, weaknesses, limitations, and potential applications as a biosensing technique. The review encapsulates critical insights into the latest and novel developments in the field of ECL-BPE, including innovative electrode designs and newly developed, novel luminophores and co-reactants employed in ECL-BPE systems, along with challenges, such as optimization of the interelectrode distance, electrode miniaturization and electrode surface modification for enhancing sensitivity and selectivity. Moreover, this consolidated review will provide an overview of the latest, novel applications and advances made in this field with a bias toward multiplex biosensing based on the past five years of research. The studies reviewed herein, indicate that the technology is rapidly advancing at an outstanding purse and has an immense potential to revolutionize the general field of biosensing. This perspective aims to stimulate innovative ideas and inspire researchers alike to incorporate some elements of ECL-BPE into their studies, thereby steering this field into previously unexplored domains that may lead to unexpected, interesting discoveries. For instance, the application of ECL-BPE in other challenging and complex sample matrices such as hair for bioanalytical purposes is currently an unexplored area. Of great significance, a substantial fraction of the content in this review article is based on content from research articles published between the years 2018 and 2023.