Detection Of Metal Ions Research Articles

Enhanced simultaneous adsorption and detection of mercury (II) using functionalized metal − organic framework with defect structures

Designing adsorption materials with high selectivity and sensitive detection is crucial for heavy metal removal. In this study, we introduced thiol, oxime, and thiourea functional groups, containing S, N, or both N and S elements, into the metal − organic framework (MOF-808, Zr6O4(OH)4(H3BTC)2(HCOO)6) to enhance its adsorption and detection capabilities for Hg2+. Moreover, by carefully controlling the molar ratio of the metal source, tricarboxyl and monocarboxyl ligands, we tailored the defects of MOF-808. The thiourea-modified materials demonstrated a record-breaking adsorption capacity (957.94 mg·g−1, 1.99 times that of unmodified materials) and distribution coefficient (743333 mL·g−1) for Hg2+, substantially exceeding that of other ions (separation factor of 105,086 for Hg2+/Zn2+). The material also showed excellent recoverability during ten consecutive cycles in Hg2+ adsorption. Furthermore, the modified MOF-808 displayed selective detection for Hg2+ with a high photochemical quenching coefficient (Ksv = 156.0 M−1). Theoretical calculations indicate that the thiourea group of MOF-808 favors the energetically advantageous Hg2+ capture and detection. These findings underscore the significance of MOF modification and defects engineering as vital strategies for optimizing the simultaneous removal and detection of heavy metal ions.

Application of a novel deep eutectic solvent as an eco-friendly medium for green extraction of cadmium from herbal medicines

In this research, hydrophobic DESs were successfully prepared using components with hydrophobic and sulfydryl group, which were applied to develop a green and eco-friendly method to extract and detect the cadmium (Cd) in herbal medicine (HM). The basic properties of the DESs were studied, which showed good hydrophobicity, low density and sufficient absorption capacity. In extraction process, the extraction efficiency (EE) of Cd employing proposed process ranged from 89.12 %∼94.59 % and the maximal enrichment factor (EF) was 46.85. The DES based method demonstrated a good linear response in the range of 1 ∼ 50 µg·L-1 with a detection limit (LOD) of 0.29 μg L-1, which was detected by Inductively coupled plasma mass spectrometry (ICP-MS). Additionally, the accuracy of method (as recoveries %) was obtained with the recoveries ranging from 98.38 %∼105.48 %. The extraction process was also compared with microwave digestion (MD) method and showed basically equivalent effect with good propensity to enrichment. The mechanism was explored by DFT calculation to reveal the interaction of extraction process. The greenness of the proposed method was also evaluated using the Green Analytical Procedure Index (GAPI) and Analytical Eco-Scale (AES), which indicated excellent environmental protection. This study successfully prepared novel DESs and established an eco-friendly and effective analytical process integrating adsorption, collection, separation and detection for the detection of heavy metals in HM, and the DESs were contributed to the first three parts as a multifunctional role. The absorption mechanism related to the formation of molecular complexes in quantum chemistry perspective, which were attribute to the electrostatic attraction and H+ exchange between Cd and adsorbent. This method showed vast potential in heavy metal research involving complex matrices such as HM and its processed products, and the proposed process provides the way for a greener alternative for Cd extraction rather than conventional polluting processes.

Biogenic synthesis of hollow carbon dots using cigarette ash for photocatalytic and sensing applications

In this research article, the synthesis of hollow carbon dots (HCDs) from cigarette ash (CA) as a precursor using simple pyrolysis method is presented. The unique hollow nature of synthesized HCDs was confirmed by high-resolution transmission electron microscopy and nitrogen physisorption techniques. HCDs, with a size of ∼ 9 nm, exhibit specific surface area of 12.1 m2/g and stimulated pore diameter of 2.1 nm. HCDs demonstrated remarkable degradation efficiency by eradicating 91 % of rose Bengal dye within 120 min under UV irradiation at pH = 5.00 and display selective and sensitive detection of Fe3+ with a detection limit of around 1.1 µM. Ecological effect of HCDs on sprouted seeds of chickpea (Cicer arietinum) and wheat (Triticum aestivum) revealed their capacity to positively influence multiple aspects of plant development. Introduction of HCDs into growth medium (water) appeared to stimulate shoot, root, and leaf growth, suggesting a potential role for HCDs in enhancing overall plant health and productivity. These findings enabled HCDs derived from CA as promising candidate for sensitive metal ions detection, environmental remediation, and plant growth enhancement. It is the first time to upcycle CA into distinctive HCDs, serving as a potent tool for detecting and breaking down environmental contaminants.

Triboelectric Nanosensor Fabricated on Robotic Platform for Self-Powered Detection of Heavy Metal Ions in Aquatic Environments

The escalation of heavy metal ions pollution, caused by the natural processes as well as human activities has emerged as a significant global challenge. The accumulation of heavy metal ions in the human body primarily occurs through water and food consumption which poses a severe threat leading to irreversible health damage. To address this issue, the World Health Organization (WHO) has established permissible limits for various heavy metal ions in drinking water, ranging from 0.003 to 3 ppm. When these limits are exceeded, water is deemed contaminated which necessitates effective monitoring and detection strategies. Robotic chemical sensing platforms have become indispensable for tackling chemical threats by detecting harmful pollutants in toxic environments. However, chemical sensors integrated with robotic platforms encounter drawback such as reliance on external power sources. In response to this challenge, our approach integrates a highly sensitive, self-powered triboelectric nanosensor (TENS) into a robotic platform charged by a thermoelectric generator (TEG) and equipped with wireless transmission capabilities. This integration enables the rapid on-site detection of heavy metal ions. The system employs copper electrodes modified with ion-selective membranes (ISM) as sensing probes and solid triboelectric contact materials. Through periodic contact-separation cycles with ionic solutions, the system generates electrical output, facilitating the detection of various concentrations of Pb2+, As3+, and Cr6+ ions. The ionophores in the respective ISMs contribute to the selective binding capacity of the sensing probe to the particular ion. This self-powered robotic platform provides an innovative and cost-effective solution for automated chemical sensing in water environments. Its advantages include the avoidance of external power sources, low-cost operation, and the elimination of the need for frequent battery replacements. With its capability for remote monitoring and detection, this system emerges as an ideal tool for preventing and controlling heavy metal ions pollution, ultimately contributing to the intelligent monitoring of heavy metal ions in aquatic environments. Keywords: Heavy metal ions, Solid-liquid triboelectric nanosensor, Robotic platform, Self-powered detection, Copper electrodes.

Surface-Immobilized Ionophore Electric-Double-Layer (EDL) Extended-Gate Field-Effect Transistors for High Sensitivity to Detection of Mercury and Lead Ions

In the field of sensors, particularly in FETs (Field-Effect Transistors), they have emerged as a promising solution for detecting heavy metal ions. These sensors offer high sensitivity, rapid response, compact and portable device sizes, and the potential for low cost. These advantages have led to their successful application in monitoring drinking water, environmental samples, and industrial wastewater, enabling rapid on-site detection of heavy metal ions.At the molecular level, certain organic molecules or coordination compounds can selectively bind to specific ions through specific chemical reactions or coordination interactions. Therefore, designing ionophores specifically for capturing or transporting particular types of ions is possible. Previous research has employed the mechanism of Ion Selective Membranes (ISM) for detecting heavy metals. However, ISMs are typically polymer coatings applied through spinning, resulting in a thick layer that leads to longer diffusion times, requiring 15 minutes or more to achieve baseline stability, with a detection limit of µM to nM .Many studies have also utilized aptamers for detecting metal ions, but aptamers are typically expensive and require controlled formation of specific structures to bind with ions. They are susceptible to interference signals from pH value or salt concentrations.In environmental or food samples, the presence of heavy metals often needs to be detected. Electric-Double-layer (EDL) sensors exhibit better stability, with a monolayer recognition layer providing shorter detection times and higher sensitivity. This study successfully developed FET (Field-Effect Transistor) metal ionophores based on a specially designed ionophore with a double-layer expanded gate, including mercury ionophore sensors and lead ionophore sensors. By defining a gate sensing area with dimensions of 500 μm x 500 μm, significant detection limits of nM to pM were achieved within minutes. The combination of FETs, EDL, and ionophores in this study's development has resulted in highly efficient, sensitive, selective, and portable detection instruments. Keywords: MOSFET, EDL, Aptamer, Ionophore, Heavy metal Figure 1

(Invited) Single-Walled Carbon Nanotube Functionalization Strategies for Monitoring Enzymatic Activity and Inhibition

Semiconducting single-walled carbon nanotubes (SWCNTs) fluoresce in the near-infrared range, which overlaps with the transparency window of biological samples, and they do not photobleach or blink. Moreover, they benefit from biocompatibility and the large surface area available for functionalization. Using tailored surface functionalization, SWCNTs can be rendered optical nanosensors, such that surface binding events or changes in the local proximity of the nanotubes translate to a modulation of the emitted fluorescence. This approach was successfully used to demonstrate the detection of small molecules, volatiles, bacteria, microRNA, proteins, metals, self-assembly processes, and active processes in vivo. We will discuss different strategies for monitoring enzymatic activity and inhibition using SWCNT-based sensors, including the incorporation of the enzyme’s target bond within a synthetic molecular complex used for suspending the SWCNTs, or by the detection of the product of the enzyme hydrolytic activity. We will also highlight recent applications of these techniques in clinically relevant samples. These findings not only showcase the potential of near-infrared fluorescent SWCNT in tracking enzymatic activity but also underscore their promising role in advancing biomedical research and applications.

Bismuth Film Electrodes: Characterization and Analytical Application

Bismuth film electrodes (BiFE) were first introduced more than two decades ago and have been regarded as a posible alternative to toxic traditional mercury electrodes, both for electro-synthesis and electro-analytical endeavors. However, despite all the associated benefits, there hasn’t been a proper characterization reported for this electrodes and their use is still limited.The present work shows the results of a physicochemical characterization of Bismuth film electrodes, as well as the application of BiFE for the detection and quantification of heavy metals (such as cadmium), which for years have been considered to be important pollutants and are toxic for humans and the environment at large; there for putting at risk the health of all organisms that come into contact with them. The analysis is carried out in a EtOH:H2O mixture at pH 5, simulating the matrix of a traditional mexican alcoholic beverage, Mezcal.The characterization includes: the calculation of the geometric area as well as the electro-active area of the electrode, the composition of the deposited film and it’s texture, and the electrical properties of the modified electrode.The analysis is carried out using Anodic Stripping Square Wave Voltammetry (ASSWV), this allows us to make use of the electrode’s ability to form strong interactions with the analyte, in a similar manner to that of mercury drop electrodes; along with the high sensitivity of this technique.

Magnetically Controllable Paper-Based Soft Robots for Colorimetric Detection of Heavy Metal Ions.

Magnetically controllable soft robots are of great interest because they have unique properties compared with conventional rigid counterparts and can be used in diverse applications such as intelligent electronics, bionics, personalized medicine, and cargo grasping. However, the fabrication of such multifunctional soft robots has been challenging because of the integration of dissimilar materials into the robot body. Herein, we designed and fabricated a soft robotic multifunctional system using conventional papers and elastomeric polymers for the colorimetric detection of heavy metal ions (Hg2+ and Fe3+) in water samples. The magnetic actuation of the platforms was shown to correlate with the type of underlying paper and magnetic particle content in the mixtures. Moreover, it was observed that actuation can also be manipulated by controlling the magnetic field strength. A proof-of-concept robotic paper-based Hg2+, Zn2+, and Fe3+ ion detection was demonstrated by combining colorimetric paper sensors and magneto-papers. Our study highlights the significant potential of paper as a material for the fabrication of effective and multifunctional untethered soft robots.

An effective turn-on/off rodamine-encapsulated UiO-67-NH2 fluorescent probe for simultaneous As5+/Fe3+ detection

The development of metal ion detection probes with high sensitivity and selectivity is of utmost importance for the promotion of public health and environmental sustainability. In this work, a series of ratiometric fluorescent probes (RhB@UiO-67-NH2) were successfully prepared using a one-pot method for the detection of metal ions, particularly As5+ and Fe3+. Notably, the ratiometric fluorescent probe RhB@UiO-67-NH2 (1:4) demonstrates dual functionality as a Fe3+ turn-off probe and an As5+ turn-on probe. The limits of detection (LODs) for As5+ and Fe3+ using RhB@UiO-67-NH2 (1:4) were determined to be 0.521 μM (39.03 ppb) and 0.107 μM (5.97 ppb), respectively, which were the lowest records of reported LMOFs so far. The fluorescence quenching of Fe3+ can be attributed to various mechanisms such as fluorescence resonance energy transfer (FRET), photoinduced electron transfer (PET), and competitive absorption (CA). Additionally, the fluorescence enhancement of As5+ is primarily due to absorbance-caused enhancement (ACE) and PET. Moreover, the composite material RhB@UiO-67-NH2 (1:4) exhibited excellent anti-interference capability and reproducibility for detecting Fe3+ and As5+. The removal efficiency of As5+ by RhB@UiO-67-NH2 (1:4) exceeded 50.9 % when the initial concentration of As5+ was below 20 mg/L. This work presents a valuable reference for future investigations and utilization of As5+ and Fe3+ sensing.

Synthesis of shape-controlled covalent organic frameworks for light scattering detection of iron and chromium ions

Fabricating covalent organic frameworks with different morphologies based on the same structural motifs is both interesting and challenging. Here, a TTA-TFP-COF was synthesized by both solvothermal and room temperature methods, with 2,4,6-Tris(4-aminophenyl)-1,3,5-triazine (TTA) and 1,3,5-tris(4-formylphenyl)-benzene (TFP) as raw material. Using different synthesis conditions and adding aniline and benzaldehyde as regulators in the synthesis process, we found that these processes could slow down the reaction speed, increase the exchange and metathesis reactions of dynamic reversible reactions, and improve the reversibility of the reaction system. Thus, controllable synthesis of TTA-TFP-COF with different morphologies, including micro-particles, hollow tubes with controllable diameters, and micro-flowers was achieved. Our further study found that metal ions, Fe3+ and Cr3+ ions, could coordinate with N and O in TTA-TFP-COF and partially destroy the structure of TTA-TFP-COF. The particle size of the TTA-TFP-COF became smaller, thus resulting in the decrease of the light scattering intensity of the COF. An excellent linear relationship exists between the light scattering changes (ΔI) and metal ions concentration (c) from 2.0 to 350.0 μM for Fe3+ and 40.0–800.0 μM for Cr3+, respectively. Thus, rapid and selective analytical methods for detecting metal ions were developed by TTA-TFP-COF here.

Fluorescence detection of Al3+ and mechanism exploration based on La-MOF

Al is the most abundant metallic element, and plays an important role in the production of life. However, excessive accumulation of Al3+ in our bodies poses potential threats to our health. Therefore, highly effective detection of Al3+ has been an important issue. In this work, a new La-MOF with a three-dimensional structure (HNU-96) has been synthesized, which can serve as effective fluorescence sensor to Al3+ detection. Due to the ion exchange between La3+ and Al3+ and the weak interaction between Al3+ and O atoms, the fluorescence quenching of the La-MOF was observed. HNU-96 shows high selectivity for Al3+ detection with the limit of detection (LOD) as low as 2.3 × 10−6 M. Furthermore, HNU-96 shows excellent anti-interference for the Al3+ detection. This work provides the feasible strategy for the metal ion detection.

Heavy metal ions monitoring using molecular ligands: Optical properties and analytical performances

AbstractHeavy metal ions are resistant to degradation and pollute a wide range of natural resources found in the environment, such as water. Detecting heavy metals is crucial for monitoring environmental safety and preventing the harmful effects of metal ion exposure. Therefore, this study has focused on Schiff‐base chemosensors, due to their efficacy in detecting metal ions, owing to their simplicity, cost‐effectiveness, rapid photophysical response, greater sensitivity, minimum detection limit, and applicability to the environmental and medical domains. Such chemosensors are crucial for ensuring public health and safety because they offer a feasible and efficient way to monitor concentrations of heavy metals. This review focuses on using spectroscopic chemosensors to detect Pb2+, Cd2+, and Hg2+ ions. The discussion includes the mechanisms and signal change properties of these chemosensors, as well as critical factors such as the limit of detection, binding stoichiometry ratio, association constant, appropriate pH, and structure. The article concludes with key findings and future perspectives, emphasizing the crucial role of metal ion monitoring devices in protecting the environment and human health.

Enzyme-Programmed Self-Assembly of Nanoparticles.

Nanoparticles are a hot topic in the field of nanomaterial research due to their excellent physical and chemical properties. In recent years, DNA-directed nanoparticle self-assembly technology has been widely applied to the development of numerous complex nanoparticle superstructures. Due to the inherent stability and surface electric repulsion of nanoparticles, it is difficult to make nanoparticle superstructures respond to molecular signals in the external environment. In fact, enzyme-programmed molecular systems are developed to allow diverse functions, including logical operations, signal amplification, and dynamic assembly control. Therefore, combining enzyme-controlled DNA systems may endow nanoparticle assembly systems with more flexibility in program design, allowing them to respond to a variety of external signals. In this review, we summarize the basic principles of enzyme-controlled DNA/nanoparticle self-assembly and introduce its applications in heavy metal detection, gene expression, proteins inside living cells, cancer cell therapy, and drug delivery. With the continuous development of new nanoparticle materials and the increasing functionality of enzyme DNA circuits, enzyme-directed DNA/nanoparticle self-assembled probe technology is expected to see significant future development.

Design and optimization of handheld alloy analysis instrument based on microjoule high pulse repetition frequency LIBS.

We briefly describe the design of a handheld metal detection instrument based on microjoule high repetition frequency laser-induced breakdown spectroscopy. The instrument uses a Raspberry Pi as the control core and a laser with a frequency of 10kHz and a single pulse energy of 100 µJ as the excitation source. In addition, a mini-putter is built into the instrument to move the laser, allowing the ablation of the sample surface line area without external auxiliary equipment. The excitation-generated plasma radiation is collected by a simple optical path and transmitted directly to the spectrometer. We also constructed and trained a Backpropagation Artificial Neural Network (BP-ANN) model based on 12 different grades of alloys and transplanted the feedback process of the BP-ANN to the Raspberry Pi, which realized the rapid classification of the 12 alloys with >95% classification accuracy on the handheld instrument.

Eco-friendly and sustainable synthesis of carbon quantum dots from waste sulfuric acid of alkylation

Waste sulfuric acid of alkylation (WSAA) poses a challenge in industrial alkylation oil production due to its substantial yield and high treatment costs. This study introduces a novel hydrothermal method that ingeniously couples the treatment of WSAA with the synthesis of high-quality carbon quantum dots (CQDs), offering a cost-effective and controllable approach. Through this method, the particle size and surface functional groups of the resulting CQDs can be precisely regulated. The average particle size tunes from 17.97 nm to 2.42 nm via increasing the hydrothermal temperature, and nitrogen-containing groups can be introduced through adding nitrogen sources during hydrothermal process. The prepared CQDs exhibit notable performance in photocatalysis and heavy metal detection, such as CQDs modified graphite carbon nitride has improved photocatalytic degradation ability and Hg (II) detection ability. Additionally, the environmental impact of the proposed method is substantially minimized, demonstrating a smaller footprint on ecosystems compared to conventional industrial disposal processes. Moreover, the economic cost associated with the method is significantly reduced by approximately 48.4 %, further highlighting its efficiency. Utilizing WSAA as a raw material for CQDs not only facilitates the recycling and sustainable utilization of waste but also enables low-cost production of high-performance carbon materials, presenting a mutually beneficial approach.

Implementation of the SN04 Roko metal sensor on a 5.56 mm caliber portable magazine feeder

Roko SN04 Metal Sensor technology and equipment are evolving and growing more advanced with time. One type of equipment that needs to consider both the user's safety and the equipment's development and safety is technological equipment used in the military. The soldiers can shoot and do so with skill. As a result, soldiers must be able to move swiftly against the enemy and vigilant when utilizing combat equipment to ensure that it is used correctly and for its intended purpose. Nevertheless, there are still several fighting tools in the military that require a lot of physical labor, making them exceedingly inefficient for the user. One such tool is the portable magazine for 5.56-millimeter ammunition. This study employed the 4D methodology, which stands for Define, Design, Develop, and Disseminate. Development research is a part of this methodology. A device for loading magazines has been created to make it easier for soldiers to move in situations where loading bullets by hand is still risky and impractical. The Roko SN04 sensor is used in the construction of this tool. One sensor that can be used as a metal detector is the Roko SN04. This magazine refill gadget uses a DC motor as a mechanic and an Arduino as a control to randomly arrange ammunition. This study's success rate was 96.67%

Synthesis, crystal structures and fluorescence recognition properties of two novel chiral coordination compounds based on alanine derivate

Two novel chiral coordination compounds {[Cd(D-pmala)(2,2′-bipy)(H2O)]⋅1·25H2O}n (1), {[Pb4(D-pmala)4(5,5′-DM-2,2′-bipy)4(H2O)2]⋅7H2O}n (2) (D-pmala = N-(4-carboxyl) benzoyl-d-alanine, 2,2′-bipy = 2,2′-Bipyridine, 5,5′-DM-2,2′-bipy = 5,5′-Dimethyl-2,2′- Bipyridine) have been successfully synthesized under hydrothermal conditions. Their structures were identified using single-crystal X-ray crystallography and characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, powder X-ray diffraction and solid-state circular dichroism spectra. Crystallographic analysis indicate that compound 1 features a "Z"-shaped one-dimensional chain structure, which further extends into three-dimensional supramolecular architectures through hydrogen-bonding interactions. Compound 2 displays a two-dimensional layer structure, a two-dimensional double-layer network structures is further formed through the hydrogen-bonding interactions. Moreover, The fluorescence recognition properties of compound 1 indicate that it is highly selective in detecting Cu2+ ions and tyrosine (Tyr) enantiomers in aqueous solutions, which indicates that compound 1 can be expected to be a bifunctional fluorescent recognition sensor to detect metal ions and amino acid enantiomers.

Recent Advances in Synthesising and Applying Magnetic Ion-Imprinted Polymers to Detect, Pre-Concentrate, and Remove Heavy Metals in Various Matrices

Magnetic ion-imprinted polymers (MIIPs) are an innovative material that combines the selectivity of ion imprinting with the ease of separation provided by magnetic properties. Recent advancements in MIIPs have shown that they have higher selectivity coefficients compared to non-imprinted materials. The synthesis of MIIPs involves creating specific recognition sites for target ions in magnetic nanomaterials. Various nanomaterials, such as graphene oxide, carbon nanotubes, and silica, have been incorporated into the IIPs to improve their analytical performance for different environmental applications, including metal extraction, monitoring, detection, and quantification. This review stresses the need to develop new monomers with a high affinity for the target analyte and to find supporting materials with groups that facilitate the effective removal of the target analyte. It also explores the influence of experimental parameters on metal determination.

Water-Stable Ln-MOF as a multi-emitting luminescent sensor for the detection of metal ions and pharmaceuticals

The development of innovative multi-emission sensors for the rapid and accurate detection of contaminants is both vital and challenging. In this study, utilizing two rigid ligands (H3ICA and H4BTEC), a series of water-stable bimetallic organic frameworks (EuTb-MOFs) were synthesized. Luminescent investigations have revealed that EuTb-MOF-1 exhibits prominent multiple emission peaks, attributed to the distinctive fluorescence characteristics of Eu(III) and Tb(III) ions. Therefore, EuTb-MOF-1 efficiently recognized various metal ions and pharmaceutical compounds through 2D decoded maps. Fe3+ and Pb2+ exhibited significant quenching effects on the luminescence of EuTb-MOF-1, which were attributed to the internal filtering effect and the interaction between Lewis basic sites within EuTb-MOF-1 and Pb2+ ions, respectively. Furthermore, EuTb-MOF-1 demonstrated high sensitivity to sulfonamide antibiotics, with detection limits of 0.037 μM for SMZ and 0.041 μM for SDZ, respectively. In addition, EuTb-MOF-1 was immobilized to prepare MOF-based test strips, enabling direct visual detection of sulfonamides as a portable sensor. With excellent water stability, multi-responsive recognition capabilities, and high sensitivity to specific analytes, EuTb-MOF-1 is a promising candidate for environmental contaminant detection in aquatic systems.

Hydrogen-bond organic-framework-based electrochemical sensor for highly sensitive determination of trace cadmium ions in environmental and e-cigarette samples

BackgroundThe heavy metal ion Cd2+ is acutely toxic, and excessive concentrations can have adverse effects on human production and life, and even lead to significant public health risks and environmental impacts. There are several mature non-electrochemical methods for heavy metal detection, but these methods are characterized by high cost, which makes it difficult to be applied to the field for timely detection. Therefore, it is necessary to prepare a new electrochemical sensor that is environmentally friendly and capable of detecting Cd2+ in the environment quickly, easily and sensitively. ResultsIn this study, hydrogen-bonded organic frameworks (HOFs) were synthesized by a simple hydrothermal reaction. The prepared materials consisted of only C, N and O and had a thin lamellar structure. The HOFs were integrated into a novel electrochemical sensor to achieve accurate detection of Cd2+ ions in real aqueous environments by square wave anodic dissolution voltammetry. The sensor has a wide linear range and a detection limit as low as 0.13 μg/L. Several real water samples, such as tap water, lake water, and e-cigarette digest, were analyzed to simulate the working environment of the sensor, and the results showed that the recoveries of Cd2+ ranged from 95.75 % to 101.2 %. SignificanceWe pioneered the detection of heavy metal ions Cd2+ in e-cigarette digestate samples with the innovative use of HOFs as the sensor material, which demonstrated the potential application in electrochemical sensing with extremely low background current value and high sensitivity, providing new ideas for environmental monitoring and public health control.