Detection Limit Of Sensor Research Articles

A New SPQC Biosensor for the Detection of a New Target of Escherichia/Shigella Genera Based on a Novel Method of Synthesizing Long-Range DNA.

The rapid and sensitive detection of Escherichia/Shigella genera is crucial for human disease and health. This study introduces a novel series of piezoelectric quartz crystal (SPQC) sensors for detecting Escherichia/Shigella genera. In this innovative biosensor, we propose a new target and novel method for synthesizing long-range DNA. The method relies on the amplification of two DNA probes, referred to as H and P amplification (HPA), resulting in the products of long-range DNA named Sn. The new target was screened from the 16S rRNA gene and utilized as a biomarker. The SPQC sensor operates as follows: the Capture probe is modified on the electrodes. In the presence of a Displace probe and target, the Capture can form a complex with the Displace probe. The resulting complex hybridizes with Sn, bridging the gap between the electrodes. Finally, silver wires are deposited between the electrodes using Sn as a template. This process results in a sensitive response from the SPQC. The detection limit of the SPQC sensor is 1 CFU/mL, and the detection time is within 2 h. This sensor would be of great benefit for food safety monitoring and clinical diagnosis.

A room-temperature ppb-level detection limit of NO2 sensor based on Cellulose/SnO2 heterojunction under UV illumination

In light of growing concerns over air pollution, particularly NO2 emissions from vehicular and industrial sources, there is a critical demand for advanced gas sensors. Traditional metal oxide semiconductors, while widely used, face challenges such as poor selectivity and high operating temperatures. In this work, we have achieved a high selectivity and room temperature NO2 gas sensor by composite of sponge-like porous cellulose with SnO2 nanoparticle. As a result, the gas sensor exhibits excellent performance in terms of high response (260.4 at 20 ppm), excellent selectivity and low detection limit (100 ppb) for NO2 gas, due to the unique sponge-like porous structure of cellulose with its high specific surface area facilitating the uniform distribution of SnO2 particles. This study not only highlights the superior sensing capabilities of cellulose-based sensors but also lays the foundation for further advancements in environmentally-friendly gas sensing applications.

A new electrochemical biosensor based on graphene oxide for rapid detection of synthetic testosterone as performance-enhancing drugs in athletes

This study showcases the successful development of a hybrid reduced graphene oxide-metal organic framework modified glassy carbon electrode (rGO-MOFs/GCE) electrochemical biosensor for the detection of synthetic testosterone (TST) as a performance-enhancing drug in athletes. The results demonstrate a linear relationship between the voltametric responses and the testosterone concentration, indicating the sensor's effectiveness in measuring TST. Furthermore, the sensor's performance in detecting TST in real human serum samples from athletes was also validated. The sensor's linear range and detection limit are comparable, if not superior, to those of other recently developed electrochemical sensors, positioning it as a promising tool for TST detection. Additionally, the method's selectivity was assessed and found to be unaffected by substances typically present in biological fluids and food samples, further affirming the sensor's reliability. The application of the rGO/MOF/GCE sensor to detecting and quantifying TST in actual human serum samples yielded favorable results. The synergistic effects of rGO and MOF, which improve the electrical conductivity and biocompatibility of MOF and the porosity and catalytic activity of rGO, are responsible for the sensor's enhanced performance in terms of sensitivity, selectivity, stability, and response time. These findings underscore the potential of the rGO/MOF/GCE sensor platform for various biomedical applications.

Development of a C3N4-based electrochemical sensing platform for the detection of circulating tumor cells in blood

This study presents a cancer diagnostics method through the development of a graphitic carbon nitride (g-C3N4)-based electrochemical sensor for detecting circulating tumor cells (CTCs) in blood. Utilizing the unique properties of g-C3N4 nanosheets combined with gold nanoparticles functionalized with DNA aptamers, the sensor exhibits remarkable sensitivity and selectivity in CTC detection. The aptamers specifically target cell surface biomarkers, enabling the precise capture and quantification of CTCs. The sensor's detection limit is an impressive 5 cells/mL, with a broad detection range from 10 to 105 cells/mL. This high-performance sensing platform not only achieves rapid and accurate quantification of CTCs but also demonstrates robustness against interference from other cell types, making it highly suitable for clinical applications. The optimized conditions for aptamer-functionalized nanoparticle concentration and incubation time ensure the sensor's efficacy, as validated in spiked blood samples. This work provides a practical and efficient approach for non-invasive cancer diagnostics, offering significant improvements over existing methods in terms of simplicity, sensitivity, and specificity for early detection and monitoring of cancer progression.

New potentiometric sensor for total phenolic assay of plant extracts

Abstract In this study, a sensitive, fast, and inexpensive new potentiometric determination method based on the Folin–Ciocalteu reagent (FCR) is proposed to determine the total phenolic content in plant extracts. For this purpose, a potentiometric-based all-solid-state-contact polyvinyl chloride membrane sensor was developed. Gallic acid compound was used as the active component (ionophore) in the developed sensor and the potentiometric behavior of the sensor was characterized. The detection limit of the selective sensor to the FCR was determined as 0.022 mol L−1 and showed a linear potential change in the concentration range of 0.0039 to 0.5 mol L−1 and a fast response time of 40 to 45 s. The developed sensor was also applied to the plant extracts and the obtained measurement results were found to be in agreement with the spectrometer results in the literature.

Influence of ZnO hexagonal pyramid nanostructures for highly sensitive and selective NO2 gas sensor

In this work, we have synthesized the ZnO Hexagonal pyramid structures (ZnO HPs) for low detection limit of NO2 gas sensors by a facile hydrothermal method. The structural, morphological analysis has been evinced by X-ray diffraction (XRD), Field Emission Scanning electron microscope (FESEM), and high-resolution transmission electron microscope (HRTEM) analysis, which witness as formed HPs are hexagonal crystal structure and it seems homogenous morphological features. The gas sensing performance of ZnO HPs towards NO2 gas at different temperature was investigated. The findings of the gas sensing showed that the ZnO HPs has a better response and recovery time towards 3 ppm concentration of NO2 gas at 270 °C. This outstanding gas sensing response of 4.31 of ZnO HPs sensor leads exceptionally strong surface contact between the NO2 gas molecules and the surface-active sites of ZnO HPs gas sensor.

Quantification of MicroRNA in a Single Living Cell via Ionic Current Rectification-Based Nanopore for Triple Negative Breast Cancer Diagnosis.

Accurate analysis of microRNAs (miRNAs) at the single-cell level is extremely important for deeply understanding their multiple and intricate biological functions. Despite some advancements in analyzing single-cell miRNAs, challenges such as intracellular interferences and insufficient detection limits still remain. In this work, an ultrasensitive nanopore sensor for quantitative single-cell miRNA-155 detection is constructed based on ionic current rectification (ICR) coupled with enzyme-free catalytic hairpin assembly (CHA). Benefiting from the enzyme-free CHA amplification strategy, the detection limit of the nanopore sensor for miRNA-155 reaches 10 fM and the nanopore sensor is more adaptable to complex intracellular environments. With the nanopore sensor, the concentration of miRNA-155 in living single cells is quantified to realize the early diagnosis of triple-negative breast cancer (TNBC). Furthermore, the nanopore sensor can be applied in screening anticancer drugs by tracking the expression level of miRNA-155. This work provides an adaptive and universal method for quantitatively analyzing intracellular miRNAs, which will greatly improve our understanding of cell heterogeneity and provide a more reliable scientific basis for exploring major diseases at the single-cell level.

Highly sensitive fluorescent nitrobenzene gas sensing by nitrogen-doped graphene quantum dots embedded in ZIF-8 nanocomposite

This study introduces a straightforward and highly sensitive luminescence gas sensor designed for the detection of nitrobenzene in gaseous state. The sensor utilizes an innovative composite composed of nitrogen doped graphene quantum dots (nGQDs) as luminescent materials, successfully encapsulated within the stable porous carrier zeolitic imidazolate framework-8 (ZIF-8). The resulting nGQD@ZIF-8 nanocomposite showed highly sensitive luminescence sensing towards nitrobenzene gas, with a wide linear detection range from 8 to 320 ppm, and the detection limits of sensor as low as 0.44 ppm. Moreover, the nGQD@ZIF-8 sensor demonstrated enhanced ppm-level sensitivity and long-term stability for nitrobenzene detection at room temperature, while maintaining high stability under varying humidity levels and exposure to high temperatures. This enhancement is attributed to the increased contact area provided by ZIF-8 matrix, facilitating adsorption of nitrobenzene molecules on nGQDs. The nGQD@ZIF-8 exhibited good selectivity towards nitrobenzene gas (57 %) compared to other nitro volatile organic compound (VOC) vapors (nitromethane and nitropropane), and almost no significant responses were observed for the other tested VOC vapors (methanol, acetone, formaldehyde, benzene). This can be attributed to the strong interaction between the electron-deficient nitrobenzene and the nGQD@ZIF-8 nanocomposite. Overall, the proposed gas sensor in this study showed high potential for a simple, efficient, and reliable detection of nitrobenzene gas in environmental monitoring.

An electrochemiluminescence sensor based on Ag NPs amplifying PDDA-modified TbPO4:Ce NWs signal for sensitive detection of lincomycin

The residue of lincomycin in water will not only aggravate the drug resistance of bacteria but also cause damage to the human body through biological accumulation. In this work, an electrochemiluminescence (ECL) aptasensor for the detection of lincomycin was constructed based on polydimethyldiallylammonium chloride (PDDA) functionalized Ce-doped TbPO4 nanowires (PDDA-TbPO4:Ce NWs) and silver nanoparticles (Ag NPs). TbPO4:Ce NWs were used as the luminophore, and PDDA was used to functionalize the luminophore to make the surface of the luminophore positively charged. The negatively charged silver nanoparticles were combined with PDDA-TbPO4:Ce NWs by electrostatic interaction. Ag NPs accelerated the electron transfer rate and promoted the ECL efficiency, which finally increased the ECL intensity of TbPO4:Ce NWs by about 4 times. Under the optimal conditions, the detection limit of the ECL sensor was as low as 4.37 × 10−16 M, and the linear range was 1 × 10 − 15 M to 1 × 10 − 5 M, with good selectivity, stability, and repeatability. The sensor can be applied to the detection of lincomycin in water, and the recovery rate is 97.7–103.4 %, which has broad application prospects.

A Cu2+ fluorescent chemosensor suitable for quantitative detection of tyrosinase in potatoes over a wide pH range.

Cu2+ as an important trace element plays an essential role in various biologic processes due to the unique redox active nature. For this reason, much effort has been made to develop effective methods for Cu2+ detection. In this study, a novel structure fluorescent chemosensor, 1-(6-(((5-(5, 5-difluoro-1, 3, 7, 9-tetramethyl-5H-4λ4, 5λ4-dipyrrolo[1, 2-c:2', 1'-f][1, 3, 2] diazaborinin-10-yl)quinolin-8-yl)oxy)methyl)pyridin-2-yl)-N, N-bis(pyridin-2-ylmethyl)methanamine (1), was synthesized and characterized by 1H and 13C nuclear magnetic resonance spectroscopy, and electrospray ionization mass spectrometry. Sensor 1 showed an obviously "on-off" fluorescence response to Cu2+ with a 1:1 binding stoichiometry by UV-vis and fluorescence spectrophotometry. The detection limit of sensor 1 to Cu2+ was determined to be 1.9µM, and the stable pH range for Cu2+ detection was from 3 to 13. Sensor 1 can be used for recognition and detection of tyrosinase in potatoes.

Fiber-Optic Photoacoustic CO Sensor for Gas Insulation Equipment Monitoring Based on Cantilever Differential Lock-In Amplification and Optical Excitation Enhancement.

A fiber-optic photoacoustic CO sensor for gas insulation equipment is proposed, which relies on F-P interferometric cantilever-based differential lock-in amplification and optical multipass excitation enhancement. The sensor has excellent characteristics of high sensitivity, antielectromagnetic interference, fast response, and long-distance detection. The photoacoustic pressure waves in the two resonators of the differential photoacoustic cell (DPAC) are simultaneously detected by two fiber-optic interferometric cantilevers and processed differentially; thereby, the gas flow noise is effectively suppressed. Based on the comprehensive analysis of the superposition of photoacoustic excitation and multipass absorption, the diameter of the resonator is determined to be 6 mm. The optical power emitted by the 1566.6 nm distributed feedback laser is increased to 500 mW by an erbium-doped fiber amplifier. The near-infrared light is reflected 30 times in the multipass cell, which improves the order of magnitude of optical effective excitation. Due to the low sound velocity of SF6 gas, the resonant frequency of the DPAC with a resonator length of 80 mm is 760 Hz. The response time to CO/SF6 gas is 93 s with a flow rate of 500 sccm. The detection limit of the CO sensor is 53 ppb, which realizes the accurate and timely perception of the SF6 decomposition derivative CO and provides technical support for trouble-free operation of gas insulation equipment.

Molecularly imprinted electrochemical sensor based on carbon nanofibers for Amiodarone determination

Amiodarone, a drug associated with significant cardiac, pulmonary, hepatic, and neurological complications, requires accurate measurement due to its narrow therapeutic window. However, the current analysis methods are time-consuming, complex, and expensive. Thus, there is a pressing need to develop a cost-effective and rapid solution for Amiodarone determination. In this study, a molecularly imprinted electrochemical sensor was designed, fabricated, and evaluated to detect Amiodarone precisely. The research involved the synthesis of magnetic nanoparticles coated with silica and the subsequent synthesis of a molecularly imprinted polymer. Carbon nanofibers were then prepared through electrospinning in a polyacrylonitrile furnace, onto which the molecularly imprinted polymer was placed. Multiple concentrations of Amiodarone were successfully determined utilizing this sensor. Following optimization, the designed sensor exhibited desirable traits such as linearity, reproducibility, precision, and accuracy. The sensor detection and quantification limit proved acceptable in whole blood and plasma samples. With its remarkable reproducibility and accurate detection of low concentrations, this molecularly imprinted electrochemical sensor offers a reliable method for quantifying Amiodarone in real samples. Moreover, its swift voltammetric response outperforms existing techniques regarding time efficiency. Overall, the developed sensor presents a valuable advancement and has the potential to benefit pharmaceutical analysis and clinical applications greatly.

Bioimpedance Measurement under Feature Combination of Time-Frequency Domain and Application for E. coli Detection

Electrochemical impedance sensors are widely used for bacterial detection and interpreted by the equivalent circuit model (ECM) to evaluate the concentration changes on the electrode interface. However, this method is mainly based on prior models and focuses on frequency domain analysis which cannot precisely describe unknown dynamic processes and a fractional surface coverage of electrode. Distribution of Relaxation Times (DRT) method, as an alternative to interpret impedance spectra can be applied to solve the problem. In this research, two electrode schemes with different modification steps were designed to collect impedance data. An Ensemble Tree-SHAP model was then adopted to quantitatively analyze the impedance data processed by ECM-DRT method in time-frequency domain and applied for the detection of Escherichia coli (E. coli). The results showed that using a dataset integrated with time-frequency domain features significantly improved the accuracy of bacterial concentration prediction. As a result, the RMSE of untrained concentration with LightGBM model was 6.4×10−4 log CFU ml−1, with the sensor detection limit about 2.69 log CFU ml−1. The research provided a tool combining time-frequency analysis for accurate prediction of bacterial concentration, which is crucial for evaluation of the antibacterial effect of long-term antibiotics on E. coli in future.

Synthesis and Application of Polymer SXFA in the Detection of Organophosphine Agents with a SAW Sensor.

The effective detection of isopropyl methylfluorophosphonate (GB, sarin), a type of organophosphine poisoning agent, is an urgent issue to address to maintain public safety. In this research, a gas-sensitive film material, poly (4-hydroxy-4,4-bis trifluoromethyl)-butyl-1-enyl)-siloxane (SXFA), with a structure of hexafluoroisopropyl (HFIP) functional group was synthesized by using methyl vinylpropyl dichlorosilane and hexafluoroacetone trihydrate as initial materials. The synthesis process products were characterized using FTIR. SXFA was prepared on a 200 MHz shear surface wave delay line using the spin-coating method for GB detection. A detection limit of <0.1 mg/m3 was achieved through conditional experiments. Meanwhile, we also obtained a maximum response of 2.168 mV at a 0.1 mg/m3 concentration, indicating the much lower detection limit of the SAW-SXFA sensor. Additionally, a maximum response standard deviation of 0.11 mV with a coefficient of variation of 0.01 and a maximum recovery standard deviation of 0.22 mV with a coefficient of variation of 0.02 were also obtained through five repeated experiments. The results show that the SAW-SXFA sensor has strong selectivity and reproducibility, good selectivity, positive detection ability, high sensitivity, and fast alarm performance for sarin detection.

Magnetic toroidal dipole resonance terahertz wave biosensor based on all-silicon metasurface

Optical sensing is crucial in many applications and has received widespread attention in recent years. Transmission spectroscopy with narrow linewidth resonances is indispensable for improving metasurface sensing performance. However, the narrower linewidth results in a smaller resonant modulation range, which seriously hinders the application of metasurfaces in sensing detection. We designed an all-silicon metasurface sensor. The structural layer of the metasurface works together with the substrate layer. Multiple magnetic ring dipoles are generated in the structural layer and multiple magnetic dipoles are generated in the substrate layer. The two work together to stimulate sharp Fano resonance, with a quality factor of up to 272.84. Based on the characteristics of metasurface, when applied to sensing and detection, the theoretical sensitivity can reach 59.64 GHz/RIU. Metasurface samples were successfully prepared using photolithography and dry etching. After characterizing the transmission spectrum of the prepared metasurface, the actual quality factor reached 76.8. At the same time, the metasurface sensor was used to detect bovine serum albumin (BSA) solutions of different concentrations. Based on the test results, it is calculated that the detection limit of the metasurface sensor for detecting BSA can reach 0.027 mg/mL, and the detection sensitivity can reach 9.7 GHz/(ng/mm2). The results of theoretical simulation and biological experiments show that the sensor has good sensing performance. This work is of great significance to the research of all-silicon metasurfaces and the application of metasurface sensors.

Gold Nanoparticle-Modified Carbon-Fiber Microelectrodes for the Electrochemical Detection of Cd2+ via Fast-Scan Cyclic Voltammetry.

Neurotoxic heavy metals, such as Cd2+, pose a significant global health concern due to their increased environmental contamination and subsequent detrimental health hazards they pose to human beings. These metal ions can breach the blood-brain barrierblood-brain barrier, leading to severe and often irreversible damage to the central nervous system and other vital organs. Therefore, developing a highly sensitive, robust, and rapid in vivo detection method for these hazardous heavy metal ions is of the utmost importance for early detection, thus initiating timely therapeutics. Detecting ultra-low levels of toxic metal ions in vivo and obtaining accurate speciation information remains a challenge with conventional analytical techniques. In this study, we fabricated a novel carbon carbon-fiber microelectrode (CFM)-based sensor that can detect Cd2+ ions using fast-scan cyclic voltammetry by electrodepositing gold nanoparticles (AuNP). We optimized electrochemical parameters that generate a unique cyclic voltammogram (CV) of Cd2+ at a temporal resolution of 100 ms with our novel sensor. All our experiments were performed in tris buffer that mimics the artificial cerebellum fluid. We established a calibration curve resulting in a limit of detection (LOD) of 0.01 µM with a corresponding sensitivity of 418.02 nA/ µM. The sensor's selectivity was evaluated in the presence of other metal ions, and it was noteworthy to observe that the sensor retained its ability to produce the distinctive Cd2+ CV, even when the concentration of other metal ions was 200 times higher than that of Cd2+. We also found that our sensor could detect free Cd2+ ions in the presence of complexing agents. Furthermore, we analyzed the solution chemistry of each of those Cd2+-ligand solutions using a geochemical model, PHREEQC. The concentrations of free Cd2+ ions determined through our electrochemical data align well with geochemical modeling data, thus validating the response of our novel sensor. Furthermore, we reassessed our sensor's LOD in tris buffer based on the concentration of free Cd2+ ions determined through PHREEQC analysis, revealing an LOD of 0.00132 µM. We also demonstrated the capability of our sensor to detect Cd2+ ions in artificial urine samples, showcasing its potential for application in actual biological samples. To the best of our knowledge, this is the first AuNP-modified, CFM-based Cd2+ sensor capable of detecting ultra-low concentrations of free Cd2+ ions in different complex matrices, including artificial urine at a temporal resolution of 100 ms, making it an excellent analytical tool for future real-time, in vivo detection, particularly in the brain.

A Surface Imprinted Polymer EIS Sensor for Detecting Alpha-Synuclein, a Parkinson's Disease Biomarker.

Parkinson's Disease (PD) is a debilitating neurodegenerative disease, causing loss of motor function and, in some instances, cognitive decline and dementia in those affected. The quality of life can be improved, and disease progression delayed through early interventions. However, current methods of confirming a PD diagnosis are extremely invasive. This prevents their use as a screening tool for the early onset stages of PD. We propose a surface imprinted polymer (SIP) electroimpedance spectroscopy (EIS) biosensor for detecting α-Synuclein (αSyn) and its aggregates, a biomarker that appears in saliva and blood during the early stages of PD as the blood-brain barrier degrades. The surface imprinted polymer stamp is fabricated by low-temperature melt stamping polycaprolactone (PCL) on interdigitated EIS electrodes. The result is a low-cost, small-footprint biosensor that is highly suitable for non-invasive monitoring of the disease biomarker. The sensors were tested with αSyn dilutions in deionized water and in constant ionic concentration matrix solutions with decreasing concentrations of αSyn to remove the background effects of concentration. The device response confirmed the specificity of these devices to the target protein of monomeric αSyn. The sensor limit of detection was measured to be 5 pg/L, and its linear detection range was 5 pg/L-5 µg/L. This covers the physiological range of αSyn in saliva and makes this a highly promising method of quantifying αSyn monomers for PD patients in the future. The SIP surface was regenerated, and the sensor was reused to demonstrate its capability for repeat sensing as a potential continuous monitoring tool for the disease biomarker.

A Multimode Microfiber Specklegram Biosensor for Measurement of CEACAM5 through AI Diagnosis.

Carcinoembryonic antigen (CEACAM5), as a broad-spectrum tumor biomarker, plays a crucial role in analyzing the therapeutic efficacy and progression of cancer. Herein, we propose a novel biosensor based on specklegrams of tapered multimode fiber (MMF) and two-dimensional convolutional neural networks (2D-CNNs) for the detection of CEACAM5. The microfiber is modified with CEA antibodies to specifically recognize antigens. The biosensor utilizes the interference effect of tapered MMF to generate highly sensitive specklegrams in response to different CEACAM5 concentrations. A zero mean normalized cross-correlation (ZNCC) function is explored to calculate the image matching degree of the specklegrams. Profiting from the extremely high detection limit of the speckle sensor, variations in the specklegrams of antibody concentrations from 1 to 1000 ng/mL are measured in the experiment. The surface sensitivity of the biosensor is 0.0012 (ng/mL)-1 within a range of 1 to 50 ng/mL. Moreover, a 2D-CNN was introduced to solve the problem of nonlinear detection surface sensitivity variation in a large dynamic range, and in the search for image features to improve evaluation accuracy, achieving more accurate CEACAM5 monitoring, with a maximum detection error of 0.358%. The proposed fiber specklegram biosensing scheme is easy to implement and has great potential in analyzing the postoperative condition of patients.

Discriminative Chromogenic Detection of Fluoride and Cyanide Ions

AbstractA silylated chalcone based sensing probe was designed and synthesized for both simultaneous as well as discriminative detection of fluoride and cyanide ions. The probe showed chromogenic response after the addition of either fluoride or cyanide ion. However, addition of water caused discoloration of the probe solution in case of fluoride ion only while no such change was observed in case of cyanide ions. The probe was found to be selective for the colorimetric detection of F‐ and CN‐ions as it did not generate any chromogenic response in presence of other analyte. For fluoride ions, the detection limit of sensor was calculated to be 0.075 μM while in case of cyanide ions; the detection limit was determined to be 0.23 and 0.44 μM in absence and in presence of water respectively. Practical utility of the proposed method was also demonstrated by testing the real water samples.

Bismuth Nanoparticles Modified Indium Tin Oxide-Coated with Polyethene Terephthalate Electrode Using Hydrothermal Method for Pb Detection

Heavy metal elements are elements with comparatively high density and are dangerous even in a minimal quantity as they can persist in the environment. The electrochemical sensor can play an essential role in detecting heavy metals. However, the electrochemical sensor has drawbacks, such as low sensitivity and a high detection limit. Bismuth nanoparticles (BiNPs) can improve the sensitivity and lower the detection limit of an electrochemical sensor by modifying the working electrode. In this study, BiNPs produced by the hydrothermal method were drop-casted on the indium-tin-oxide (ITO) coated with polyethene terephthalate (PET) film (BiNPs/ITO-PET). The effect of the hydrothermal reaction was studied by varying the hydrothermal reaction period (5, 6, 7, and 8 h). X-ray Diffraction (XRD) was used to characterize the phase presence, and the morphology of BiNPs was characterized using a transmission electron microscope (TEM). The BiNPs/ITO-PET electrode was subjected to electrochemical characterization using cyclic voltammetry (CV) and the detection of Pb(II) using differential pulse anodic stripping voltammetry (DPASV). The BiNPs/ITO-PET electrode showed good electrochemical performance in detecting Pb(II).