Ensuring food safety requires advanced hybrid materials capable of detecting trace antibiotics within complex plant matrices. We introduce a laser-induced molecular engineering (LIME) strategy to fabricate a selenium-integrated samarium hydroxide and graphene (Gr/Sm(OH)3:Se) nanocomposite engineered for direct electrochemical detection of sulfamethoxazole (SMX) in cultivated lettuce tissue. Unlike conventional laser processing techniques that primarily induce surface texturing, LIME enables molecular-level integration of functional elements, producing defect-rich interfaces with enhanced electron mobility and abundant active sites. Comprehensive characterization confirms that localized photothermal and photochemical effects promote the uniform incorporation of Se into the Sm(OH)3 lattice and convert surface M–OH groups into M–O linkages, thereby generating holes in the O 2p valence band and improving both electron transfer kinetics and the selectivity toward SMX adsorption. The resulting sensor exhibits high sensitivity (1.83 µA (µg/g)−1 cm− 2), excellent selectivity, and long-term stability (> 30 days), enabling reliable trace-level detection without artificial sample spiking. Analysis of real samples further reveals higher SMX accumulation in lettuce irrigated with SMX-contaminated water. This study establishes LIME as a versatile and controllable approach for molecularly engineering electrode materials, thereby advancing the real-world monitoring of antibiotic residues in plants.

Excessive use of furazolidone (FRZ) in livestock increases the likelihood of FRZ residues in food products, posing a significant risk to human health. Therefore, monitoring FRZ levels in food is crucial. Although electrochemical detection is feasible and economically viable, conventional electrodes encounter fouling and poor selectivity issues. Here, we developed an efficient sensing electrode using a novel nanocomposite comprising a cerium bismuth oxide (CeO0.65BiO0.35) nanostructure integrated with laser-induced graphene (LIG) for selective and sensitive FRZ detection. The CeO0.65BiO0.35-LIG exhibits strong synergy in which the oxygen-vacancy-rich CeBi oxide provides abundant redox-active Ce3+/Ce4+ sites, thereby accelerating electron transfer and promoting the multielectron reduction of FRZ. Consequently, the CeO0.65BiO0.35-LIG-modified electrode enables rapid, high-sensitivity FRZ detection with a low limit of detection (0.00397 μM), limit of quantification (0.01 μM), and broad linear response range (0.01-129 μM). Recovery rates >97% in milk and water samples underscore its effectiveness for food-safety monitoring.

Despite notable progress in wearable biosensors, continuous monitoring of therapeutic drugs in wound environments remains underexplored. Herein, we report the construction of atomic Se sites on polar CeO2 (100) surfaces for the continuous antibiotic monitoring of complex wound exudates, using tetracycline as a model drug. Comprehensive characterization reveals a redox-mediated two-step selenization of CeO2 (100) surfaces: (i) H2SeO3 reduces CeO2 to Ce2O3, generating oxygen vacancies filled by SeO32-, and (ii) Ce2O3 is re-oxidized as SeO32- is reduced, yielding stable Se-O-Ce motifs. These atomic-scale configurations restructure the pristine surface and induce spatially selective antifouling, wherein protein adsorption preferentially occurs on native Ce-O domains while the Se-O-Ce regions remain electrochemically accessible. As a result, Se-CeO2 retains similar to 45 % of its original response after 30 h continuous operation, compared to similar to 10 % for pristine CeO2. Furthermore, the atomic Se sites offer dynamic flow responsiveness in a microfluidic wound model, exhibiting different lag times under varying perfusion rates. This behavior reflects individual variations in vascular perfusion and metabolism and demonstrates that atomic-scale surface engineering enables personalized pharmacokinetic monitoring in complex wound environments. This study pioneers the application of selenized ceria surfaces and opens new avenues for advanced biosensing and other biomedical applications.

The impact of nanoparticle's dispersion within a specified matrix governs the functionality of the resulting nanocomposite; however, the interfacial properties between the nanoparticles and matrix components can also play a role but have not been sufficiently emphasized. Therefore, we explored a fully functional interface between samarium tellurate (STO) and laser-induced graphene (LIG) utilizing a method that effectively dispersed STO within the LIG matrix via interfacial engineering. This STO-LIG nanocomposite was applied to enhance the electrochemical detection of clothianidin (CLN), which is a neonicotinoid often used in pest control with persistent adverse effects on non-target organisms and pollinators. However, previous nanocomposite-modified electrodes for detecting CLN did not meet practical requirements and were not evaluated for monitoring soil. In the designed nanocomposite, STO provided highly selective adsorptive sites for CLN adsorption, while LIG offered robust electronic conductivity. To optimize the activity, the composite interfaces were engineered using a bottom-up assembly strategy with a precipitation-cum-deposition method. Comprehensive assessments revealed that STO was effectively dispersed through the gradual chemisorption of STO onto LIG via the C-O-Te(Sm) bond, a newly discovered active site. Owing to this remarkable active site, the STO-LIG nanocomposite exhibited high sensitivity (1.33 mu A mu M-1 cm(-2)) and selectivity (>95 %) in detecting CLN in soil and water samples. Overall, this study provides insights into the design and formation of a nanocomposite with an effective interface and good charge transfer characteristics.

The increasing demand for pollutant monitoring devices has driven advances in electrochemical (EC) sensors. However, the shortage of efficient sensing electrodes and the lack of optimal preparation conditions both limit their growth. Therefore, synthesis protocols for constructing product-specific EC sensors are required. In this study, we developed a platinized glass microfluidic chip (pGMC) to produce tailored lanthanum tellurate (LTO) for the reliable detection of imidacloprid (IMD). The resulting LTO was highly pure and exhibited an amorphous structure that optimized its performance, and it was easily used to fabricate a disposable sensing electrode. This electrode performed well in outdoor environmental samples and demonstrated improved IMD detection capabilities, with over 95 % selectivity. The achieved linear dynamic range (0.01 to 70 mu g/g) and detection limit (0.003 mu g/g) are well suited to practical applications. We also explicitly investigated the design of the pGMC and the selective EC sensing mechanism with supporting evidence. Overall, this study demonstrates the feasibility of using pGMC to produce customized LTO for onsite IMD detection, which can also be applied to the design of other customized nanomaterials.

The improper or excessive use of antibiotics in humans and animals has caused antibiotic residues to accumulate in the environment, posing substantial risks to human health. Ceftriaxone (CRO), among the most commonly prescribed antibiotics for a variety of infections, poses particular risks because it is excreted in its active form and persists in the environment; thus, it can potentially contribute to antimicrobial resistance and disturb aquatic microbial communities. To address this issue, we developed an effective, easy-to-use electrochemical sensor utilizing a nickel selenide (NiSe) and laser-induced graphene (LIG) composite for the highly sensitive sensing of CRO in environmental and urine samples. The simple laser-induced photothermal process effectively carbonized a polyimide precursor into LIG and seamlessly integrated the resulting LIG with NiSe nanostructures. The resulting composite exhibited excellent physicochemical properties and synergistic effects, with its high surface area and configuration facilitating the oxidation of CRO through the redox properties of Ni2+ and Ni3+. In addition, the composite clearly outperformed its individual components, NiSe and LIG. A NiSe-LIG-modified electrode demonstrated high sensitivity, with a limit of detection of 4.02 nM and a linear range of 0.01-38.91 μM. Furthermore, real-time monitoring attained recovery rates of 96.4-98.6 % in various environmental water samples and 96.4-98.5 % in urine samples, confirming the practical utility of the sensor for rapid, low-cost, and portable CRO detection. A platform with these aspects would overcome the shortcomings of laboratory-based analyses requiring complex sample preparation, which is important for both environmental protection and antimicrobial resistance control.

With the growing incidence of cancer, cytostatic drugs that block the growth of cancer cells are being increasingly consumed, raising concerns regarding pharmaceutical pollutants. Halogen -containing antineoplastic fluorouracil (FLU) residues are continuously released into environmental water and soil surfaces, and upon entering the environment, they cause carcinogenic risks to environmental organisms and are hazardous to human health. Thus, on -site monitoring devices must be designed to prevent such hazardous pollutants from spreading to water, land, and ecosystems. We used erosion hydroxylation to fabricate a Cu -intercalated titanium aluminum carbide (TAC) MXene (Cu-Ti 3 Al 1- x C 2 -OH x or Cu-TAC-3) for the on -site monitoring of cytotoxic FLU in environmental samples. The three-dimensional Cu-TAC-3 network was prepared using a simple, environmentally friendly magnetic stirring process, wherein Cu groups were intercalated into the hydroxylated TAC active sites to enhance the electrochemical properties. The physicochemical properties of Cu-TAC-3 were characterized spectroscopically. Furthermore, a Cu-TAC-3-modified glassy carbon electrode (GCE) was fabricated that could electrochemically detect FLU under various conditions, achieving a good sensitivity of 0.7033 mu A/ mu M cm -2 , linearity between 0.001 to83.76 mu M, and a low limit of detection of 0.54 nM (70 ng mL -1 ). Cu-TAC-3/GCE demonstrated excellent electrochemical activity toward FLU even in real environmental samples, with a recovery of above 97 % from spiked samples. These sensors are therefore practical for the on -site electrochemical monitoring of FLU.

Eco-friendly biomass-derived nanocarbons have gained considerable attention for detecting metallic pollutants, such as iron, in the environment. In addition, fluorescence probes are in high demand due to the growing need for iron detection in various organic solvents. Herein, we synthesize luminescent biomass-derived carbon nanoparticles (BMCNPs) from Kalanchoe pinnata plant leaves using a simple single-step solvothermal method. The synthesized BMCNPs emit red fluorescence in non-aqueous environments (organic solvents) and exhibit excellent fluorescence stability and solubility in both aqueous and non-aqueous media. The quenching of fluorescence emissions from BMCNPs in non-aqueous medium, facilitated by the addition of Fe(III) ions, demonstrates the ability of BMCNPs to serve as probes for detecting trace quantities of iron impurities. Experimental results confirm that the fluorescence from the BMCNPs is influenced by a ligand-to-metal charge transfer-assisted dynamic quenching mechanism. The proposed sensor is suitable for the real-time detection of iron in organic solvents, where iron contamination occurs due to the corrosion of iron metal. The fluorescence quantum yield of the probe is determined to be similar to 11 %. The detection limit for Fe(III) in N,N-dimethylformamide using the synthesized probe is determined to be 1.9 mu M. This study provides a platform for detecting Fe(III) ions in non-aqueous media. The proposed probe overcomes the limitation of Fe(III) ion-specific aqueous solubility, enabling the detection of Fe(III) ions in non-aqueous media due to the solubility and red emission specificity of BMCNPs in non-aqueous environments.

The release of heavy metal ions, especially hexavalent chromium [Cr(VI)], from industrial processes poses significant health and environmental risks. Cr(VI) does not readily degrade but can be reduced to the less toxic trivalent form [Cr(III)] that exhibits lower adsorption, making it easier to manage and remove from environmental systems. This paper proposes a single-step solvothermal method to synthesize fluorescent multiatom-doped (N, K, Cl, Mg, and Ca) carbon dots (MACDs) from Kalanchoe pinnata leaves (carbon precursor) and ethanol (solvent). These MACDs serve as effective photocatalysts for Cr(VI) reduction under one sun illumination (AM 1.5 G conditions). The reaction achieved a 91% Cr(VI) removal from a 20 ppm deionized water solution in 420 min and complete removal (100%) in an acidic solution with the same initial concentration in 120 min. The MACDs demonstrated excellent photocatalytic performance across tap, river, and lake water. These biomass-derived MACDs demonstrate strong potential for effective Cr-contaminated water remediation.

The improper disposal of antibiotics in water bodies and using contaminated wastewater in irrigation severely damage the environment. Despite efforts to monitor these contaminants, effective detection methods are limited. Here, we design and develop a novel microfluidic electrochemical (EC) sensor for on-site detection of trimethoprim (TMP) using a selenite-enriched lanthanum hydroxide (La(OH)(3):SeOx) working electrode and a polyimide (PI)-filter integrated microfluidic channel (MFC), thus termed a "mu TMP-chip". For the first time, we introduced a new two-pronged strategy for enhancing TMP detection: i) incorporating selenite into the La(OH)(3) lattice to improve charge transfer properties and ii) using a laser-processed PI filter in the MFC to trap and isolate complex biomasses. Material characterizations confirmed that incorporating selenite into the La(OH)(3) lattice initiated La-O-Se bond formation and enhanced hybridization between the La 4f and O 2p orbitals. This process created holes in the O 2p valence band and improved the charge transfer properties, thus enhancing both sensitivity and selectivity. EC studies confirmed that when the PI filter is not used in the MFC, the mu TMP-chip experiences a 15-45 % drop in efficiency. The scalable mu TMP-chip offers cost-effective, highly reproducible TMP detection in soil and water.

The presence of trace water impurities in organic solvents can significantly influence chemical reactions and product quality; thus, the accurate detection of water content in these solvents is a critical requirement for industrial applications. Accordingly, an eco-friendly, effective, and economical sensor for detecting trace quantities of miscible water in organic solvents is required for industrial applications. In this study, we synthesized biomass-derived multi-atom-doped carbon dots (MACDs) as fluorescent probes and employed them for the detection of trace amounts of water impurities in several water-miscible organic solvents. The MACDs exhibited stable dual-color fluorescence emission under ultraviolet light irradiation and red and blue emissions in organic solvents and water. The fluorescence quantum yield was approximately 11 %, which indicates an excited intraparticle proton transfer response due to an increase in the water content within a wide response range from 0 % to 100 % (v/v) in organic solvents. The intensity of the red emission signal at 670 nm gradually decreased with an increase in the water content in the organic solvent. The MACDs could detect water with an instant response time of 55 s, a high sensitivity, and low limits of detection of 0.08 %, 1.36 %, 0.03 %, 0.04 %, 0.12 %, and 0.05 % (v/v) in ethanol, acetonitrile, dimethylformamide, methanol, isopropanol, and tetrahydrofuran, respectively. Hence, biomass-derived MACDs can serve as efficient and eco-friendly water sensors in organic solvents.

Emerging pharmaceutical pollutants pose a threat to both human and environmental health. The removal and monitoring of such pollutants necessitate the use of practical on-site monitoring devices; however, the designs of such devices are underdeveloped. This study involves the fabrication of a low-cost sensor based on bariumincorporated copper oxide (Ba-CuO) for the on-site monitoring of the cytotoxic drug methotrexate (MTRX) in water and sediment samples. The tenorite structure of CuO was slightly enriched with Ba ions at the td sites, distorting the tetrahedron and enhancing its electrochemical properties. Ba-CuO was obtained from Cu(NO3)2 and Ba(OH)2 by a ligand exchange protocol and was characterized using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray analysis. In addition, the Ba-CuO sensor was tested under various conditions, and it could detect MTRX at concentrations as low as 0.4 nM, with a high sensitivity of 1.3567 mu A mu M-1 cm- 2. On-site monitoring yielded recoveries of greater than 93 % from spiked samples, thus exhibiting excellent reproducibility and stability. Therefore, the developed method is practical and has no matrix effect on the MTRX sensor.

Elevated levels of plasma homocysteine (Hcy) increase the risk of various diseases, but early diagnosis and monitoring can help prevent and treat such diseases. However, current diagnostic assays that quantify Hcy levels fail to detect more complex and rare proteins related to certain mutations, i.e., N-homocysteinylated proteins (NHcy-proteins), which are important for clinical decision-making. Therefore, the discrete diagnosis of Hcy in each mutated protein is in high demand. In this study, we design and fabricate a disposable microfluidic Hcy sensor chip (MHS-chip). Specifically, we utilize a laser direct-writing carbonization approach to mount a microfluidic channel filled with three-dimensional Cu-doped graphene and sensing electrodes onto a polyimide film for the first time. This microfluidic channel promotes the binding of N-Hcy-proteins and isolates the Hcy from a 10 & mu;L plasma sample, while the sensing electrode is used for detection. The MHS-chip has a linear dynamic range of 0.01-124 & mu;M and a detection limit of 2.9 nM, which is suitable for clinical application. Moreover, it exhibits good selectivity, high reproducibility, and real-time applicability in plasma samples. Overall, the MHS-chip is an efficient, low-cost device for the early diagnosis of Hcy and can be applied in point-of-care tests.

The overuse of pesticides to increase essential food production adversely affects the environment and human health. Methiocarb (MTC) is the most effective insecticide (acaricide) for controlling mollusks in soil and plants. However, MTC has poisoning effects on non-targeted living organisms and soil. Therefore, MTC monitoring in soil and water samples is necessary to mitigate its poisoning effect on living organisms. In this study, we explored novel architectures of barium vanadate multi-layered graphene (BaV2O6-ML-Gr) nanocomposites as highly se-lective and sensitive electrodes for MTC detection. These materials were synthesized using a facile precipitation method and ultrasonication. They were then utilized as electrode matrices for the electrochemical quantification of MTC in environmental samples. Subsequently, the electrochemical performance of the BaV2O6-ML-Gr/screen-printed carbon electrode (SPCE) was evaluated using differential pulse voltammetry, which revealed a high sensitivity of 1.0805 mu A/(mu M-1 cm-2) with a low detection limit of 8 nM and an adequate linear response of 0.01-64.9 mu M. The real-time quantification of MTC using BaV2O6-ML-Gr/SPCE was conducted with different soil and water samples, which provided acceptable recovery results for MTC. The results showed that BaV2O6-ML-Gr/ SPCE can be used for the on-site electrochemical analysis of MTC.

Chloramphenicol (CAP) is a harmful antibiotic that inevitably enters our food chain through natural or manmade means. Its ineradicable residue pollutes soils and water, accumulates in plants and animal products, and eventually affects human health. An ultrasensitive method for detecting and monitoring CAP is therefore urgently required. Herein, we report an ultrafast extraction and amperometry detection method based on a graphitesulfate-modified electrode for detecting CAP in soil, water, and food samples. The graphite sulfate is prepared by the oxidation method and its structural properties are comprehensively investigated. The developed sensor electrode showed a wider linear range of 0.3-32.0 mu g kg-1 and an ultralow detection limit of 0.1 mu g kg-1, both of which meet the European Commission Reg 1871/2019 reference points for action. The method works well with both meat and plant samples, achieving CAP recoveries ranging from 90.8 to 99.1% even at low concentrations. Moreover, the sensor electrode shows more than 95% selectivity toward CAP detection in the soil, water, and food matrices. The developed method exhibits good repeatability and reproducibility in the analysis of real samples.

Pesticides are inevitably used in intensive agrochemical practices to meet the global food demands of a continuously increasing population; however, the widespread and heavy use of pesticides disturbs the ecological balance and poses a threat to human health. Carbofuran (CBF) is a representative carbamate insecticide that affects the environment and human health. Therefore, highly accurate on-site CBF residue monitoring is essential for environmental media samples. This study realized the sensitive and rapid electrochemical sensing of CBF using monoclinic strontium vanadate (pyrovanadate)-supported graphene nanocomposite (SV-Gr). The SV-Gr nanocomposite was synthesized using the hydrothermal method, and the physicochemical properties of the SV-Gr nanocomposite were characterized via spectroscopic analyses. The SV-Gr-modified screen-printed carbon electrode (SPCE) exhibited good analytical performance in CBF detection, with a high sensitivity of 1.05 mu A mu M-1 cm-2 and an acceptable linear range (0.01-17.91 mu M). Moreover, SV-Gr/SPCE exhibited good selectivity for highly interfering carbamate pesticides. Furthermore, the applicability of the proposed SV-Gr/SPCE sensor was investigated in environmental media samples, which achieved greater than 96 % of recoveries for all samples; thus, it is suitable for the sensitive and rapid detection of CBF in a real environment.

The increasing use of pesticides poses significant threats to both the environment and human health. Safety assessments for controlling or monitoring such potential hazards require on-site sensing devices with facile fabrication and ultralow detection limits. In particular, electrochemical assays satisfy some of these re-quirements; however, to date, their electrodes have not demonstrated satisfactory stability, selectivity, or sensitivity. This paper reports the development of a simple, efficient electrochemical sensor based on a composite of samarium stannate (Sm2Sn2O7) and laser-induced graphene (LIG) for detecting fenamiphos (FNPS) in-secticides in environmental and food samples. A laser photothermal reaction was employed to simultaneously carbonize and amorphize the surface of a Sm2Sn2O7-polyimide film. This single-step reaction furnished a three-dimensional porous LIG network with Sm2Sn2O7 clusters. The resulting Sm2Sn2O7-LIG nanocomposite exhibited enhanced physicochemical properties, surpassing those of its individual components, i.e., LIG and Sm2Sn2O7. Moreover, a glassy carbon electrode modified with Sm2Sn2O7-LIG was employed for the detection of FNPS at remarkably low concentrations of 7.69 nM, exhibiting a high sensitivity of 1.5137 mu A mu M(-1)cm(-2). Real-time monitoring resulted in a recovery rate of more than 96 % from spiked environmental and food samples, con-firming its practical applicability for sensitive FNPS detection.

The growing population and global food demands have encouraged the use of pesticides to increase agricultural yields; however, the irrational use of pesticides threatens human health and the environment. Carbaryl (CRBL) is the most widespread insecticide and severely affects soil, water systems, and human health. Thus, it is crucial to monitor CRBL residues in the environment and vegetable samples. This study reports the rapid and sensitive electrochemical detection of CRBL based on a pyrochlore-type lanthanum tin oxide (LSO) nanoparticles (NPs)-modified screen-printed carbon electrode (SPCE). A low-temperature hydrothermal method was employed to prepare the LSO NPs. The structural properties of the LSO NPs were characterized by X-ray diffraction, Raman, and X-ray photoelectron spectroscopy analyses. The LSO NPs/SPCE demonstrated good electroanalytical performance for CRBL detection, with a low detection limit of 0.4 nM (0.08 µg/L) and a sensitivity of 1.05 µA/(µM cm2). Furthermore, the LSO NPs/SPCE exhibited high selectivity among highly interfering carbamate and organophosphorus pesticides, which share similar mechanisms of action. Additionally, the LSO NPs/SPCE sensor achieved > 90% recovery for the detection of CRBL in soil, water, and vegetable samples, thus verifying its suitability for the rapid detection of CRBL.

Diclofenac (DCF) is used to reduce inflammation substance, which causes pain and inflammation, in the human body. However, the overconsumption of DCF may cause life-threatening problems in humans. Therefore, it is necessary to detect DCF levels in human urine samples because it is excreted in the urine after taking DCF. We developed a facile synthetic route for obtaining an exfoliated graphite (Gr)-supported cobalt ferrite (EGr-Co1.2Fe1.8O4) nanocomposite using an ultrasonication method that does not involve calcination. The prepared EGr-Co1.2Fe1.8O4 nanocomposite was examined by various physicochemical characterization methods. The nanocomposites were successfully agglomerated on the exfoliated Gr surface under the optimized experimental conditions. An EGr-Co1.2Fe1.8O4 nanocomposite was employed to fabricate electrochemical sensors for the sensitive electrochemical detection of DCF in human urine samples. The EGr-Co1.2Fe1.8O4 modified screen-printed carbon electrode sensor shows excellent electrochemical activity toward DCF with excellent sensitivity (1.059 mu A mu M-1 cm(-2)) within an acceptable linear concentration range (0.01-23.1 mu M) and a very low limit of detection (1 nM).