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Traditional DNA walkers face enormous challenges due to limited biostability and reaction kinetics. Herein, we designed a self-driven close-looped DNAzyme walker (cl-DW) with high structural biostability and catalytic activity that enabled rapid electrochemiluminescence (ECL) detection of pesticide residue acetamiprid. Specifically, cl-DW exhibited increasing ability to resist nuclease degradation with a 570-fold longer half-degradation time than that of the single-stranded DNAzyme walker (ss-DW) due to the protected DNA terminal. Furthermore, cl-DW achieved high catalytic activity with a 4.3-fold faster reaction kinetic than that of ss-DW due to the circularized nanostructure of an available catalytic domain. Consequently, we utilized cl-DW as a signal amplifier and tin-based sulfide (SnS 2) nanoflowers as ECL emitters to construct an ECL aptasensor, which realized the sensitive detection of acetamiprid with a limit of detection of 0.85 nM. This work provides a reliable approach to exploring DNA walkers with high catalytic activity and better biostability for molecular monitoring. • An electrochemiluminescence aptasensor was designed for acetamiprid detection. • Spatial folding effect enhanced catalytic activity of close-looped DNAzyme walker. • Close-looped DNAzyme walker had improved structural biostability. • This method had satisfactory results for practical application of small molecule. [ABSTRACT FROM AUTHOR]

The indiscriminate use of pesticides is one of the factors directly impacting bee populations. However, limited information is available on the pesticide effects on solitary bees, especially in Neotropical countries. In this scenario, this study evaluated the survival and histopathological effects caused by the neonicotinoid insecticide acetamiprid (7 ng/μL) and the fungicide azoxystrobin (10 ng/μL) in the midgut and parietal fat body of the solitary bee Centris analis. Female and male newly-emerged bees were orally exposed for 48 h to the pesticides, or alone or in combination, under laboratory conditions. The exposure to the insecticide reduced the survival of males, while the mixture reduced survival in both sexes. Acetamiprid promoted a reduction in the number of regenerative nests in the midgut, alterations of fat body cells by increasing carbohydrates in trophocytes, and reduction of oenocyte size, and increased the frequency of pericardial cells in the advanced activity stage. Both pesticides caused changes in HSP70 immunolabelling of midgut from males at the end of pesticide exposure. Comparatively, the effects on males were stronger than in females exposed to the same pesticides. Therefore, acetamiprid alone and in mixture with fungicide azoxystrobin can be harmful to males and females of Neotropical solitary bee C. analis showing lethal and sublethal effects at a concentration likely to be found in the environment. [Display omitted] • Fungicide azoxystrobin promoted the increase of HSP70 in the solitary bees' midgut. • Insecticide acetamiprid reduced survival of Centris analis. • Male bees were more sensitive to insecticide exposure than females. • Acetamiprid, alone and in mixture with azoxystrobin can be harmful to C. analis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A rainbow-like multicolor LFIA based on PRCNPs is developed for detecting acetamiprid. • PRCNPs exhibit advantages in catalytic activity, antibody utilization, and signal readout. • PRCNPs-LFIA achieves single-to-multicolor output via the etching of GNRs. • PRCNPs-LFIA enables qualitative, semi-quantitative, and quantitative analysis. Traditional lateral flow immunoassay (LFIA) using single-color labels has limitations in indistinct color change and restriction to the single-mode readout, which can hardly meet the demands of high-performance detection. Inspired by the multiple colors of the rainbow, we outline a multicolor LFIA using multibranched trimetallic platinum–rhodium-cobalt nanoparticles (PRCNPs) as signal labels to initiate multicolor conversion for diverse and multicolor readouts. The intrinsic properties of PRCNPs including their trimetallic composition, multibranched morphology, and strong absorption in the visible spectrum, confer advantages in catalytic activity, antibody utilization, and signal readout. Through the synergistic integration of the catalytic PRCNPs with the etching of gold nanorods, PRCNPs-LFIA enables multicolor readouts in a rainbow-like manner. PRCNPs-LFIA allows for qualitative analysis of acetamiprid, a widely-used neonicotinoid insecticide, at 2 ng mL−1. It also provides semi-quantitative analysis based on the discrimination of at least 10 colors. Furthermore, quantitative analysis can be conducted across multiple color spaces within the range of 0.01-10 ng mL−1, achieving a lowest detection result of 0.006 ng mL−1. The recoveries of acetamiprid in food samples detected by PRCNPs-LFIA in grayscale and multiple color space modes are 87.35%-103.59%, 85.56%-114.33%, 86.14%-114.77%, and 87.81%-112.01%, respectively, with all coefficients of variation below 15%. These results demonstrate the feasibility and accuracy of PRCNPs-LFIA in practical applications. Overall, this study illustrates the potential of multifunctional PRCNPs in the development of multicolor LFIA and broadens the biosensing strategies for point-of-care testing. [ABSTRACT FROM AUTHOR]

Metal-organic framework play an important role in developing novel detection techniques. Herein, an ultrathin two-dimensional (2D) metal-organic framework nanosheet (Cu-TCPP) assembled microflower was successfully synthesized and applied for ultrasensitive detection. The high detection performance of Cu-TCPP microflower was attributed to high-capacity aptamer adsorption and specific desorption resulting from numerous approachable active sites, and its ultrathin nanosheets microflower-like structure. Moreover, the Cu-TCPP microflower had overcame the disadvantages of 2D MOF nanosheets which tended to agglomerate. Moreover, it exhibited excellent fluorescence quenching performance as a donor for fluorescence resonance energy transfer. Acetamiprid, a new chloronicotinic neurotoxic insecticide was used as the model analyte. The ultrasensitive sensor was developed by combining the Cu-TCPP microflower with deoxyribonuclease Ⅰ signal enhanced fluorescence. When acetamiprid was present, the fluorescent labeled aptamer probe was selectively bound to acetamiprid and desorbed from the Cu-TCPP microflower, resulting in fluorescence recovery. Subsequently, DNase Ⅰ was used to cleave the DNA strands of the aptamer probe, and acetamiprid was released to participate in a new cycle. The detection limit of the assay was as low as 5.56 pg/mL with a linear range 50.00 pg/mL∼5.00 μg/mL, and it was a universal platform to detect other analytes. [Display omitted] • The Cu-TCPP microflower was synthetized with superior active sites and FRET performance. • The Cu-TCPP microflower and DNase I assisted amplification was combined for ultrasensitive aptasensor. • The aptasensor for sensitive and selective detection of acetamiprid with LOD 5.56 pg/mL and linear range 50 ∼ 5,000,000 pg/mL. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cauliflower-like super-hydrophobic SERS substrate by two-step laser processing. • The enhancement factor of the SERS substrate reaches 5.9 × 109 for R6G. • The detection limit of the SERS substrates for acetamiprid is as low as 10-5 g/L. Residues of organic pesticides continue to accumulate in the human body through the food chain, posing a serious threat to health. Therefore, the efficient and sensitive detection of pesticide residues is crucial. Surface-enhanced Raman scattering (SERS), as a powerful spectroscopic technique, holds great potential for the trace detection of pesticides. In this study, a cauliflower-like SERS substrate fabricated via a two-step laser processing is proposed for highly sensitive detection of acetamiprid. The cauliflower-like structure features a large surface area, providing numerous hotspots and abundant adsorption sites for the target molecules. Furthermore, the rich micro/nano structures on the surface confer super-hydrophobicity properties to the substrate, effectively enriching the analyte and greatly enhancing the SERS performance. As a result, the cauliflower-like super-hydrophobic substrate demonstrates a detection limit as 10-15 M for the typical dye analyte (R6G), with an enhancement factor of 2.6 × 108. Additionally, the substrate exhibits excellent signal reproducibility with a relative standard deviation of 8.33 %. In practical pesticide detection, the detection limit for acetamiprid on orange is 10-4 g/L, significantly surpassing the national standard. In conclusion, the cauliflower-like super-hydrophobic substrate enhances the sensitivity, uniformity, reproducibility, and reliability of SERS signals in detection process, showing tremendous potential in the field of food safety. [ABSTRACT FROM AUTHOR]

The work was based on N-(4-Aminobutyl)-N-ethylisoluminol (ABEI)-functionalized Fe-MIL-101 and gold nanoparticles (AuNPs) as sensing materials, and an electrochemiluminescence (ECL) aptasensor was constructed for detecting acetamiprid. As a metal-organic framework (MOF) material, Fe-MIL-101, was renowned for its unique three-dimensional network structure and efficient catalytic capability. ABEI, a common ECL reagent, was widely applied. ABEI was introduced into the Fe-MIL-101 structure as a luminescence functionalization reagent to form Fe-MIL-101@ABEI. This approach avoided limitations on the loading capacity of luminescent reagents imposed by modification and encapsulation methods. With character of excellent catalytic activity and ease of bioconjugation, AuNPs offered significant advantages in biosensing. Leveraging the reductive properties of ABEI, AuNPs were reduced around Fe-MIL-101@ABEI, resulting in the modified luminescent functionalized material denoted as Fe-MIL-101@ABEI@AuNPs. An aptamer was employed as a recognition element and was modified accordingly. The aptamer was immobilized on Fe-MIL-101@ABEI@AuNPs through gold-sulfur (Au–S) bonds. After capturing acetamiprid, the aptamer induced a decrease in the ECL signal intensity within the ABEI-hydrogen peroxide (H 2 O 2) system, enabling the quantitative detection of acetamiprid. The aptasensor displayed remarkable stability and repeatability, featured a detection range of 1×10−3-1×102 nM, and had a limit of detection (LOD) of 0.3 pM (S/N=3), which underscored its substantial practical application potential. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides specifically target insect subtypes of nicotinic acetylcholine receptors. Acetamiprid (ACE: C10H11ClN4), the neonicotinoid insecticide , is used to control crop insect pests worldwide. It is a nitrile, monochloropyridine, and carboxamidine that is highly soluble and accessible to waterways. There, it causes neurotoxic and oxidative perturbance to non-target organisms. The unionid mussel Chamabradia rubens is a common Northern River Nile suspension feeder. The current study aimed to assess ACE filtration from waters by C. rubens , and whether this biological power can reduce ACE effects on fish. Removal of ACE by C. rubens was assessed using LC-MS/MS. Zebrafish Danio rerio adults were exposed to different sublethal doses of ACE in the presence or absence of C. rubens in their aquaria. The results showed that mussels could remove significant ACE amounts from water, where it accumulated mostly in the digestive gland. The presence of C. rubens in zebrafish aquaria having ACE was accompanied by significant upregulation of antioxidant enzyme gene transcripts and total H 2 O 2 scavenging, in contrast to mussel-free ACE-exposed groups. Meanwhile, liver triglycerides rose 5-6-fold in response to ACE in the "Fish-Only" groups, indicating an ACE-induced hepatotoxicity. Also, Insulin-like growth factor 1 (igf1) and fish body mass increased more in "Fish + Mussel" groups than in the "Fish-Only" ones. In aggregate, these findings suggest that the Nile mussel could reduce the oxidative stress and metabolic changes induced in fish by ACE. This can contribute valuable environmental and economic benefits upon the use of this mussel as a biofilter. [Display omitted] • The neonicotinoid insecticide acetamiprid induces oxidative stress in zebrafish. • Nile clam Chambardia rubens removes significant amounts of acetamiprid in waters. • C. rubens in zebrafish aquaria alleviated acetamiprid-induced toxicity. • C. rubens was proven as a successful biofilter against acetamiprid adverse impacts. [ABSTRACT FROM AUTHOR]

This paper presents sensitive and selective fluorescence detection of acetamiprid using oxidised single-walled carbon nanohorns and cryonase-assisted signal amplification. Reaction of the system with acetamiprid and cryonase, leading to a great change in fluorescent intensity in a dose- and time-dependent manner, and acetamiprid can be quantified accordingly. [Display omitted] • A new fluorescent approach for the detection of acetamiprid is presented. • It is based on oxidized single-walled carbon nanohorns and cryonase-assisted signal amplification. • The system showed excellent selectivity and detection performance, with no interference from other pesticides. To address the low accuracy of pesticide residue detection in traditional Chinese medicine, we developed a biosensor for acetamiprid detection. First, an oxidized single-walled carbon nanohorn capable of adsorbing and quenching fluorescence was prepared. Second, a novel fluorescence sensing system was constructed based on this nanomaterial. The detection performance of the sensor system was evaluated, which revealed that fluorescence quenching by the biosensor was primarily due to the adsorption of the aptamer by the nanomaterials. Optimal conditions were found to be a nanomaterial mass concentration of 800 ng/mL and an incubation time of 70 min, which resulted in the best fluorescence response. Under these optimal conditions, the system was used to detect acetamiprid residues in traditional Chinese medicine. The fluorescence intensity showed a strong linear relationship with acetamiprid concentration, with a correlation coefficient of 0.9985 and a detection limit of 6.33 ng/mL. In the sample test, the biosensor demonstrated high accuracy, with good average recovery rates and low relative standard deviation. The system showed excellent selectivity and detection performance, with no interference from other pesticides. [ABSTRACT FROM AUTHOR]

Electrochemical aptasensor is a great tool for simultaneously assessing harmful pesticide residues in agricultural products and foods. This study ingeniously designed an electrochemical aptasensor based on dual signal amplification strategies for concurrent detection of various pesticide residues. Firstly, poly(diallyldimethylammonium chloride)-functionalized reduced graphene oxide (PR) and Au-Pt-Pd trimetallic nanoflowers supported on HP-UiO66-NH 2 were creatively employed together as substrates to load more aptamers, ascribed to the improved conductivity, abundant sites and a large electrochemical effective surface area. Secondly, ferrocene-cysteine gold nanoparticles supported on CeMOF(Ⅲ, Ⅳ) and methylene blue-loaded MOF235 were innovatively engineered to build two distinctive signal labels, which displayed comparable large and stable signal currents among other redox molecule/MOF composites. Additionally, PR contributed further signal amplification. Consequently, the constructed aptasensor showed superior performance for simultaneous detection of acetamiprid (AD) and malathion (ML), with linear ranges from 10 pM to 0.1 μM and detection limits of 4.8 pM for AD and 0.51 pM for ML. Moreover, the aptasensor performed well in the assay of AD and ML in Chinese cabbage samples with high accuracy compared with a high-performance liquid chromatography-tandem mass spectrometry method. Overall, the strategies proposed herein provided a useful and potential route for general development of electrochemical aptasensors to simultaneously detect multiple pesticide residues. • PR and NFs/HP-UiO66-NH 2 were used together as great substrates to load aptamers. • Redox molecule/MOF composites were synthesized and selected for signal amplification. • FcCysAu/CeMOF(Ⅲ, Ⅳ) and MB/MOF235 were firstly used to build signal labels. • The proposed aptasensor performs well on detecting AD and ML in real samples. [ABSTRACT FROM AUTHOR]

The elimination of pesticides from polluted water is critical due to their harmful environmental and biological impacts. Recently, there has been interest in utilizing natural polymer-based adsorbents as an eco-friendly approach to eliminate or reduce the levels of water pollutants. In this work, we synthesized an antimicrobial and magnetic bionanocomposite consisting of carboxymethyl gond katira- grafted - poly(3-aminobenzoic acid) with iron oxide and zinc oxide NPs (CMT- g -P3ABA/ZnO/Fe 3 O 4) through an in situ polymerization reaction and examined for its ability to adsorb the pesticide acetamiprid (AP). The bionanocomposite was characterized using several analytical techniques, including spectroscopy; XRD presented the crystalline structure of ZnO/Fe 3 O 4 in the CMT- g -P3ABA amorphous matrix. The ZnO/Fe 3 O 4 partially aggregated formation and exhibited polyhedral crystal shapes was depicted by electron microscopy images, vibrating sample magnetometer (45.06 emu/g), porosimetry (5.52 m2/g), and thermal (Chair yield of approximately 43.83 %) and elemental analyses. Under various conditions, including solution pH (4–9), adsorbent dosage (0.005–0.025 g), time of contact (10–30 min), and pesticide preliminary concentration (200–400 mg/L) in 10 mL of the solution. Based on this research, Adsorption data were perfectly fitted by the Freundlich isotherm model with R AP 2 = 0.99038, while the pseudo-second-order (PSO) model well-explained adsorption kinetics with R AP 2 = 0.99847. AP adsorption to the CMT-g-P3ABA/ZnO/Fe 3 O 4 bionanocomposite was successful due to hydrophobic interactions, hydrogen bonding, and π-π stacking. Furthermore, adsorption-desorption experiments demonstrated that the bionanocomposite could be regenerated after three reuse cycles without considerable loss of pesticide removal performance. The bionanocomposite also exhibited promising antimicrobial activity in contradiction to test bacteria. [Display omitted] • Magnetic antimicrobial nanocomposite based on carboxymethyl gond Katira- grafted -poly(3-aminobenzoic acid) prepared • Nanocomposite employed as a biosorbent for pesticide removal • Maximum adsorption capacity of the biosorbent for pesticide was 1000 mg/g. • Biosorbent displayed antibacterial activity in contradiction of E. coli and S. aureus [ABSTRACT FROM AUTHOR]

In this study, a dual - mode aptasensor based on the competition mechanism was constructed to detect acetamiprid (ACE) residues in vegetables. With 3,5-dicarboxyphenylboronic acid (5-bop) as a ligand, a bimetallic RuZn-based metal-organic framework (RuZn-MOF) was synthetized by applying a hydrothermal method to achieve efficient electrochemiluminescence (ECL) and electrochemistry (EC) dual-mode detection of ACE. Compared with the monometallic Zn-based metal - organic framework (Zn-MOF) of the same structure, the bimetallic RuZn-MOF exhibited a greater ability to transfer electrons due to the synergistic effect between different metal and the 5-bop ligand. Meanwhile, the complementary DNA (cDNA) probe for bonding the ACE aptamer was modified with ferrocene (Fc) and methylene blue (MB). When the target pesticide of ACE was present, ACE competed with the cDNA probe, so that the ECL achieved the "signal on" and the EC achieved the "signal off". ECL and EC detection being combined, the results showed that the two detection methods corroborated each other and worked synergistically, i.e., they effectively reduced the systematic errors and background signals, and improved the reliability of the detection. The linear ranges of the ECL and EC aptasensors were 1 pg/mL-1 μg/mL with the limit of detection (LOD) of 0.33 pg/mL, and 1 fg/mL-1 ng/mL with LOD of 0.33 fg/mL (S/N=3), respectively. The dual-mode strategy had good stability and specificity, providing some valuable support for the detection and analysis of other substances. • Bimetallic MOF with self-enhanced luminescence was synthesized. • A novel dual-mode aptasensor based on the competition mechanism was constructed. • An "on-off-on" mode electrochemiluminescence sensor was assembled. • An "off-on-off" mode electrochemistry sensor was assembled. • Limit of detection of acetamiprid residues in vegetables was as low as fM level. [ABSTRACT FROM AUTHOR]

• Acetamiprid showed low bioconcentration potential in Xenopus laevis tadpoles. • Acetamiprid may have toxic effects on Xenopus laevis tadpoles. • Exposure to acetamiprid induces disorders in the antioxidant defense system. • Exposure to acetamiprid alters transcriptome and metabolome profiles in tadpoles. • Imbalances in purine metabolism and amino acid metabolism are potential molecular mechanisms. Acetamiprid is a neonicotinoid commonly detected in aquatic ecosystems, with residual concentrations of up to 0.41 mg/L in surface water, posing a threat to the health of nontarget aquatic organisms. However, studies on the potential toxicity and underlying mechanisms of action of acetamiprid on nontarget aquatic organisms are limited. This study investigated the acute and short-term toxicity of acetamiprid to Xenopus laevis tadpoles. A 96-h acute toxicity test determined the LC 50 of acetamiprid to be 32.1 mg/L. After 28 days of exposure to 1/10 and 1/100 LC 50 concentrations, tadpole samples were collected for bioconcentration elimination analysis, biochemical analyses, transcriptomics, and metabolomics studies to comprehensively evaluate the toxic effects of acetamiprid and its underlying mechanisms. The results, indicating bioconcentration factors (BCFs) < 1, suggest that acetamiprid has a low bioconcentration in tadpoles. Additionally, oxidative stress was observed in treated Xenopus laevis tadpoles. Transcriptomic and nontargeted metabolomic analyses identified 979 differentially expressed genes (DEGs) and 95 differentially metabolites in the 0.321 mg/L group. The integrated analysis revealed that disruption of purine and amino acid metabolic pathways potentially accounts for acetamiprid-induced toxic effects in tadpoles. The disruptive effects of acetamiprid on valine, leucine and isoleucine biosynthesis; and aminoacyl-tRNA biosynthesis metabolic pathways in tadpoles were validated through targeted metabolomics analysis. These findings are crucial for assessing the risk of acetamiprid to nontarget aquatic organisms. [ABSTRACT FROM AUTHOR]

Rapid and sensitive detection for acetamiprid, a kind of widely used neonicotinoid insecticide, is very meaningful for the development of modern agriculture and the protection of human health. Highly stable electrochemiluminescence (ECL) materials are one of the key factors in ECL sensing technology. ECL materials prepared by porous materials (e.g., MOFs) coated with chromophores have been used for ECL sensing detection, but these materials have poor stability because the chromophores escape when they are in aqueous solution. Therefore, the development of highly stable ECL materials is of great significance to improve the sensitivity of ECL sensing technology. In this work, by combining etched metal-organic frameworks (E-UIO-66-NH 2) as carrier with Tris(4,4′-dicarboxylic acid-2,2′-bipyridine)Ru(II) chloride (Ru(dcbpy) 3 2+) as signal probe via amide bonds, highly stable nanocomposites (E-UIO-66-NH 2 -Ru) with excellent ECL performance were firstly prepared. Then, using MoS 2 loaded with AuNPs as substrate material and co-reactant promoter, a signal off-on-off ECL aptamer sensor was prepared for sensitive detection of acetamiprid. Due to the excellent catalytic activity of E-UIO-66-NH 2 -Ru and MoS 2 @Au towards K 2 S 2 O 8 , the ECL signals can be enhanced by multiple signal enhancement pathways, the prepared ECL aptamer sensor could achieve sensitive detection of acetamiprid in the linear range of 10−13 to10−7 mol L−1, with the limit of detection (LOD) of 2.78ⅹ10−15 mol L−1 (S/N = 3). After the evaluation of actual sample testing, this sensing platform was proven to be an effective method for the detection of acetamiprid in food and agricultural products. The E-UIO-66-NH 2 -Ru prepared by linking Ru(dcbpy) 3 2+ to E-UIO-66-NH 2 via amide bonding has very high stability. The synergistic catalytic effect of MoS 2 and AuNPs enhanced the ECL signal. By exploring the sensing mechanism and evaluating the actual sample tests, the proposed signal "on-off" ECL sensing strategy was proved to be an effective and excellent ECL sensing method for sensitive and stable detection of acetamiprid. The conventional cathodic ECL response uses K 2 S 2 O 8 as co-reactant. Generally, K 2 S 2 O 8 can only be activated by participating in redox reactions on the electrode surface, and then the reactive intermediate SO 4 •− is produced to participate in the subsequent luminescence process (Route 1). However, since the amount of the active intermediate SO 4 •− limits the luminescence efficiency of the luminophore, increasing the production rate of the active intermediate SO 4 •− is an effective way to improve the efficiency of ECL. In this study we used MOFs material (E-UIO-66-NH 2) etched by thermal treatment as the carrier of the luminophore Ru(dcbpy) 3 2+, and the etched E-UIO-66-NH 2 exposed more amino groups, which can effectively catalyze the activation process of K 2 S 2 O 8 and produce more SO 4 •− (Route 4). Not only that, the Mo4+/Mo6+ active sites produced by 3D MoS 2 nanoflowers involved in the redox reaction on the electrode surface can also effectively catalyze the activation process of K 2 S 2 O 8 (Route 2). AuNPs grown in situ on the MoS 2 surface can also effectively catalyze the activation process of K 2 S 2 O 8 (Route 3). Therefore, we constructed a sandwich-type ECL sensor based on multiple signal enhancement strategy to achieve efficient and sensitive detection of acetamiprid in the range of 10−13 to 10−7 mol L−1 with a detection limit of 2.78ⅹ10−15 mol L−1. This provides an effective method for the sensitive detection of acetamiprid in food and agricultural products. [Display omitted] • The synergistic effect of Ru(dcbpy) 3 2+ and –NH 2 showed more excellent ECL response. • MoS 2 , AuNPs and E-UIO-66-NH 2 promote catalysis co-reactants and enhance ECL response. • Ru(dcbpy) 3 2+ can enter larger pore diameter inside E-UIO-66NH 2 to increase the load. • E-UIO-66-NH 2 exposes more amino groups, which enhances the catalytic of co-reactant. [ABSTRACT FROM AUTHOR]

Health of honey bees is threatened by a variety of stressors, including pesticides and parasites. Here, we investigated effects of acetamiprid, Varroa destructor , and Nosema ceranae , which act either alone or in combination. Our results suggested that interaction between the three factors was additive, with survival risk increasing as the number of stressors increased. Although exposure to 150 μg/L acetamiprid alone did not negatively impact honey bee survival, it caused severe damage to midgut tissue. Among the three stressors, V. destructor posed the greatest threat to honey bee survival, and N. ceranae exacerbated intestinal damage and increased thickness of the midgut wall. Transcriptomic analysis indicated that different combinations of stressors elicited specific gene expression responses in honey bees, and genes involved in energy metabolism, immunity, and detoxification were altered in response to multiple stressor combinations. Additionally, genes associated with Toll and Imd signalling, tyrosine metabolism, and phototransduction pathway were significantly suppressed in response to different combinations of multiple stressors. This study enhances our understanding of the adaptation mechanisms to multiple stressors and aids in development of suitable protective measures for honey bees. We believe our study is environmentally relevant for the following reasons: This study investigates combined effects of pesticide, Varroa destructor , and Nosema ceranae. These stressors are known to pose a threat to long-term survival of honey bees (Apis mellifera) and stability of the ecosystems. The research provides valuable insights into the adaptive mechanisms of honey bees in response to multiple stressors and developing effective conservation strategies. Further research can identify traits that promote honey bee survival in the face of future challenges from multiple stressors to maintain the overall stability of environment. [Display omitted] • The interaction of the three stressors was additive for survival. • Acetamiprid had no effect on honey bee survival but damaged midgut tissue. • Varroa destructo r was the dominant factor threatening honey bees. • The triple stressor combination inhibited the expression of MRJPs genes. • The stressors suppressed Toll, tyrosine metabolism, and phototransduction pathways. [ABSTRACT FROM AUTHOR]

Acetamiprid is the only neonicotinoid registered in the European Union because the risks of neonicotinoids to honey bees and other pollinators are strictly regulated. Herein, we orally exposed honey bee colonies to sublethal concentrations of acetamiprid (20 μg/L) under isolated conditions. After one month of continuous exposure, the emerging bees and queens were collected and analyzed via high-throughput label-free quantitative proteomics using a data-independent acquisition strategy. Six and 34 significantly differentially expressed proteins (DEPs) were identified in the emerging bees and queens, respectively. Mrjp3 was the only DEP found in both sample types/castes, and its opposite regulation illustrated a differential response. The DEPs in the emerging bees (H/ACA RNP, Rap1GAP, Mrjp3, and JHE) suggested that sublethal exposure to acetamiprid affected cell cycle-related signaling, which may affect the life history of workers in the colony. The DEPs with increased levels in queens, such as Mrjps 1–4 and 6–7, hymenoptaecin, and apidaecin 22, indicated an activated immune response. Additionally, the level of farnesyl pyrophosphate synthase (FPPS), which is essential for the mevalonate pathway and juvenile hormone biosynthesis, was significantly decreased in queens. The impaired utilization of juvenile hormone in queens supported the identification of additional DEPs. Furthermore, the proteome changes suggested the existence of increased neonicotinoid detoxification by UDP-glucuronosyltransferase and increased amino acid metabolism. The results suggest that the continuous exposure of bee colonies to acetamiprid at low doses (nanograms per gram in feed) may pose a threat to the colonies. The different exposure routes and durations for the emerging bees and queens in our experiment must be considered, i.e., the emerging bees were exposed as larvae via feeding royal jelly and beebread provided by workers (nurse bees), whereas the queens were fed royal jelly throughout the experiment. The biological consequences of the proteomic changes resulting from sublethal/chronic exposure require future determination. [Display omitted] • Low acetamiprid exposure increased abundance of immune response proteins in queens. • Results support activation of immune pathways by cyanoamidine neonicotinoids. • Juvenile hormone synthesis and utilization proteins were affected in queens. • Cell cycle-related proteins suggest life history implications in emerging bees. • Results are consistent with earlier observed modulation of immunity by pesticides. [ABSTRACT FROM AUTHOR]

Acetamiprid (AAP) is a common neonicotinoid pesticide and their residues have emerged as a widely concerned issue on vegetables and fruits. In this work, a facile electrochemical surface-enhanced Raman spectroscopy (EC-SERS) method with one step of "mixing and detection" was proposed for detection of AAP. Wherein, screen printed electrode (SPE) was modified by dropping silver nanoparticles (AgNPs) onto the SPE surface. Compared to the normal SERS detection, the EC-SERS had a 5-fold enhancement in SERS signal with an applied potential at –0.7 V. Under the optimal applied potential, a wide linear range from 0.1 μM to 1000 μM was achieved with a low limit of detection (LOD, 0.04 μM), about 7-fold lower than that of the normal SERS method (LOD, 0.31 μM). Density functional theory (DFT) calculation revealed that the van der Waals force between AAP molecules and AgNPs was greatly enhanced. Besides, the EC-SERS method was successfully applied for the detection of AAP in Brassica chinensis L., and the results correlated well (R2 =0.9760) with those obtained from liquid chromatography-tandem mass spectrometry (HPLC-MS). The proposed method featured in easy operation, rapid detection and high sensitivity, which can act as a promising tool for monitoring pesticide residues in food samples. • Potential-powered EC-SERS strategy was developed for acetamiprid detection. • An electrochemical potential of − 0.7 V was applied to enhance AAP SERS signal. • DFT was used to investigate the non-covalent interaction between AgNPs and molecules. • EC-SERS strategy exhibits 7 times higher detection sensitivity than SERS. [ABSTRACT FROM AUTHOR]

Carbofuran and acetamiprid pose the highest residual risk among pesticides found in wolfberries. This study aimed to degrade these pesticides in wolfberries using a multi-array dielectric barrier discharge plasma (DBD), evaluate the impact on safety and quality and explore their degradation mechanism. The results showed that DBD treatment achieved 90.6% and 80.9% degradation rates for carbofuran and acetamiprid, respectively, following a first-order kinetic reaction. The 120 s treatment successfully reduced pesticide contamination to levels below maximum residue limits. Treatment up to 180 s did not adversely affect the quality of wolfberries. QTOF/MS identification and degradation pathway analysis revealed that DBD broke down the furan ring and carbamate group of carbofuran, while replacing the chlorine atom and oxidizing the side chain of acetamiprid, leading to degradation. The toxicological evaluation showed that the degradation products were less toxic than undegraded pesticides. Molecular dynamics simulations revealed the reactive oxygen species (ROS) facilitated the degradation of pesticides through dehydrogenation and radical addition reactions. ROS type and dosage significantly affected the breakage of chemical bonds associated with toxicity (C 4 –O 5 and C 2 –Cl 1). These findings deepen insights into the plasma chemical degradation of pesticides. [Display omitted] • Unqualified data of wolfberry was firstly investigated and as degradation reference. • DBD degraded 90.64% and 80.92% of carbofuran and acetamiprid, respectively. • The degradation was gained atomic-scale insight by molecular dynamics simulations. • Products and toxicity were studied jointly to examine the safety of CP degradation. • ROS caused degradation through dehydrogenation and radical addition reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reuse and recycling of spent adsorbent via thermal treatment in an inert atmosphere. • FTIR and TGA-TPD/MS resolved degradation products and mechanism of acetamiprid degradation. • XPS and EDS analyses confirmed the formation of active materials in pores and at the surface. • Added value nitrogen-doped carbon from adsorbed pesticides with a stable capacitance of 65F g−1. Reuse and/or recycling of spent adsorbents is taking a central role in modern thinking and catalyzed carbonization is the way forward. Herein we explore the carbonization of adsorbed acetamiprid, in an inert atmosphere, as a way of recycling and producing nitrogen-rich carbon material for potential use in supercapacitors. Added value material and the reuse of the adsorbent were achieved by carbonization at 700 °C under argon. The formation of a nitrogen-doped carbon layer as an active material on the adsorbent, bonded through a C-Si linkage, has been conclusively verified through elemental composition quantification using XPS and EDX measurements. Two-stage catalytic decomposition and condensation of the adsorbed pesticide is followed by TGA and TPD-MS. Attained carbon-based materials give stable Faradaic capacitance with a slight dependency on the number of adsorbing cycles. Capacitance calculated with respect to the adlayer carbon material reaches values as high as 610 F g−1. Galvanostatic Charge/Discharge measurement confirmed the stability of explored materials with a slight increase in capacitance over 1000 cycles. The presented results envisage electroactive materials preparation from environmental pollutants, adding value to spent adsorbents. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs)@N-(4-aminobutyl)-N-ethylisoluminol (ABEI)@Titanium dioxide nanorods (TiO 2 NRs) were used as sensing materials to produce a unique encapsulated nanostructure aptasensor for the detection of acetamiprid residues in this work. ABEI, an analog of luminol, was extensively used as an electrochemiluminescence (ECL) reagent. The ECL mechanism of ABEI- hydrogen peroxide (H 2 O 2) system had connections to a number of oxygen-centered free radicals. TiO 2 NRs improved ECL response with high electron transfer and a specific surface area. AuNPs were easy to biolabel and could catalyze H 2 O 2 to enhance ECL signal. AuNPs were wrapped around TiO 2 NRs by utilizing the reduction property of ABEI to form wrapped modified nanomaterials. The sulfhydryl-modified aptamer bound to the nanomaterial by forming gold-sulfur (Au–S) bonds. The aptamer selectively bound to its target with the addition of acetamiprid, which caused a considerable decrease in ECL intensity and enabled quantitative detection of acetamiprid. The aptasensor showed good stability, repeatability and specificity with a broad detection range (1×10−2-1×103 nM) and a lower limit of detection (3 pM) for acetamiprid residues in vegetables. Overall, this aptasensor presents a simple and highly sensitive method for ECL detecting acetamiprid, with potential applications in vegetable safety monitoring. Schematic diagram of material synthesis and aptasensor assembly process. [Display omitted] • Encapsulated nanostructures combining TiO 2 NRs, ABEI, and AuNPs were used for sensing. • TiO 2 NRs, ABEI, and AuNPs serve dual roles in constructing the aptasensor. • Combining sensor materials speeds up PE modification and lowers experimental errors. • The sensor was successfully applied to detect acetamiprid residues in vegetables. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the protective effects of N-Acetyl-L-cysteine (NAC) and S-methyl- L-cysteine (SMC) against hepatic oxidative stress and brain damage induced by acetamiprid (ACP) in rats, which were evaluated by histopathological changes, measuring serum biomarkers and antioxidant defense systems. In this study, 42 rats were randomly divided into 6 groups and administered by intraperitoneally for one week: the control group, the sham group (normal saline), ACP alone (5 mg/kg) (group1), NAC alone (160 mg/kg) (group2), ACP + SMC (100 mg/kg) (group3), ACP + NAC (group 4) and ACP + NAC + SMC (group 5). Our results showed that acetamiprid induces liver injures including infiltration of inflammatory cells, congestion and altered histo-architecture and brain damages including gliosis, hyperemia and necrosis. The biochemical analyses showed that acetamiprid significantly altered the structural and biochemical profiles of liver which may be due to the loss of integrity of cell membranes. Furthermore, antioxidant parameters results of ACP group revealed that glutathione (GSH) and total antioxidant capacity (TAC) levels decreased significantly, while lipid peroxidation (LPO) content and glutathione-S-transferase (GST) and catalase (CAT) activities increased in both tissues (P < 0.05), suggesting tissue oxidative damage, which was also confirmed histopathological. Conversely, administration of NAC and SMC ameliorated LPO, GSH content and antioxidant enzymes system considerably (P < 0.05) in both tissues. Moreover, NAC and SMC administration also improved liver and brain malfunction. These results indicate that both NAC and in to a lesser amount SMC have a potent antioxidant protection in both tissues of rat against ACP-induced oxidative stress. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the comparative effects of pesticides Chlorfenapyr, Dimethoate and Acetamiprid on the health of Cirrhinus mrigala under long term exposure. Eighty C. mrigala were divided in four equal groups; one control and three treated groups. The blood was collected from both control and treated groups at intervals of 10th, 20th and 30th days for hemato-biochemistry and histopathological alterations. The result indicates significant difference (P < 0.05) in RBCs, Hb, PCV and MCHC whereas elevation in WBCs and Platelets counts were recorded. In 10th day sampling, MCV value of Dimethoate and Acetamiprid treatment had no difference in comparison with the control group, however it is significantly increased (P < 0.05) in rest of sampling. The MCH value of exposed fish showed significant increased (P < 0.05) after 20th and 30th days for Chlorfenapyr and after 30th days for Acetamiprid exposure while insignificantly increased for rest of sampling. It was also found that these pesticides significantly decrease (p < 0.05) the T3 and T4 levels while increase in the TSH, cortical, ALP, AST, ALT and LDH levels in the serum of the treated fishes in contrast to control group. Similarly, histopathological analysis of gills and liver showed significant alterations in all the treated groups. Toxicity trends of these pesticides was ranked as Chlorfenapyr > Acetamiprid > Dimethoate. It is concluded that indiscriminate use of such pesticides poses a noxious threat to non-target organisms, harm the ecosystems and jeopardizes human health. [ABSTRACT FROM AUTHOR]

Herein, gold nanoparticles (Au NPs) in solution protected by various concentration of DNA at different aggregation states were found to have different quenching effect to the fluorescence of carbon dots (CDs). Au NPs wrapped up in more amount of DNA were able to quench the fluorescence of CDs more effectively, and vice versa. Based on this phenomenon, a facile and novel fluorescence sensing platform without labeling was constructed by designing the sequence of DNA as the aptamer of the detection target. With the addition of specific molecule, taking acetamiprid as representative, DNA was prior to bind with target and the Au NPs became less protected, leading to the fluorescence recovery of the CDs. Experimental results showed that the fluorescence of CDs was linearly recovered by acetamiprid in the concentration range of 7.8 × 10−9–1.4 × 10−6 mol/L, with the detection limit of 1.5 × 10−9 mol/L. This promising sensor might provide a new aspect for exploring the versatile application of CDs in various fields. Image 1 • Au NPs in different aggregation state are discussed as the quencher of CDs with clear mechanism. • Taking DNA protected Au NPs as quencher renders ease of finding the specific molecule for recovery of CDs fluorescence. • Acetamiprid, by designing the DNA sequence as its aptamer, has been sensitively and selectively detected via this method. • More targets may be involved in CDs fluorescence sensing platform. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) has been widely used for detecting pesticide residues. Nevertheless, the spectral interference of sample matrix still exists, and the simultaneous detection of multiple pesticides is challenging. In this work, specific simultaneous detection of acetamiprid (ACE) and carbendazim (CBZ) in complex sample matrix was achieved by using two Raman tag molecules (prussian blue, PB; 4-(mercaptomethyl) benzonitrile, MBN) whose peaks were in the Raman-silent spectral window. Two Raman nanoprobes were synthesized by adding MBN and PB into the Au and Ag core-shell gap and coupled with two complementary DNA (cDNA), respectively. Meanwhile, two aptamer-incubated Fe 3 O 4 /Au nanoparticles were used as capture molecules. Results showed that the Raman intensity at 2077 cm−1 and 2228 cm−1 had an inverse tendency with ACE and CBZ concentrations, respectively. Under the optimal conditions of aptamer, cDNA concentration, and reaction volume ratio, the SERS aptasensor showed a wide linear range of 0.01 ∼ 1 mg/kg with limit of detection of 9.43 μg/kg to ACE and 9.17 μg/kg to CBZ. The result of recovery experiment showed that there was no significant difference between SERS method and HPLC method (p > 0.05). It turned out that the SERS aptasensor had a good resistance to spectral interference of matrix and easy separation, which can specifically detect ACE and CBZ in complex matrix simultaneously. SERS combined with nano-sensor elements will be conducive to the on-site detection of various hazardous substances in food safety. • A SERS aptasensor realized simultaneous detection of carbendazim and acetamiprid. • Two nitrile-mediated molecules (MBN, PB) were added into Au and Ag core-shell gap. • The SERS sensor can eliminate spectral interference of biomolecules in food matrix. • Fe 3 O 4 /Au nanoparticles were used as capture molecules for rapid enrichment. [ABSTRACT FROM AUTHOR]

Acetamiprid (ACMP) is a second-generation neonicotinoid that has been extensively used in the last few years. The present study examined the toxic effects of ACMP on the pancreas and glucose homeostasis through the evaluation of histological and biochemical changes and the possible ameliorative role of fenugreek seed extract (FG). Fifty adult albino rats were divided into 5 groups: negative control, positive control, FG-treated, ACMP-treated, and ACMP + FG-treated groups by oral gavage for 12 weeks. The ACMP-treated group highlighted significant elevations in plasma glucose, glycosylated haemoglobin levels (HbA1c), serum amylase, and serum lipase, along with a decrease in plasma insulin levels. In addition, significant increases in tumour necrosis factor- alpha (TNF-α) and malondialdehyde (MDA) were associated with reductions in the levels of interleukin 10 (IL-10), glutathione peroxidase, and catalase. Moreover, glucose-6-phosphatase and glycogen phosphorylase were significantly increased, with a significant reduction in hexokinase and liver glycogen stores. These biochemical changes were associated with histological changes in pancreatic sections stained by haematoxylin and eosin, Masson stain, and Orcein stain. ACMP-treated cells showed a marked reduction in β- cell immune reactivity to insulin, with pronounced p53, and beclin 1 immune expression. The use of FG with ACMP induced partial protection except for hexokinase and glycogen phosphorylase. [Display omitted] • Acetamiprid increases glucose hemostasis, glycosylated hemoglobin, and reduces insulin levels. • Acetamiprid increases TNF-α, MDA levels, while reducing IL-10, IL-10, and catalase. • Acetamiprid causes vacuolation of pancreatic cells, decreases p53 and beclin 1 expression, and affects insulin levels. • Fenugreek and Acetamiprid provide partial protection, except for hexokinase and glycogen phosphorylase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochromic MIP/IrO 2 /ITO was designed for acetamiprid detection. • Electrochromic properties were determined both quantitatively and qualitatively. • MIP/IrO 2 /ITO electrode exhibited linear range of 4.29–38.6 nM. • The LOD and sensitivity was estimated as 2.72 nM and 47.2 μA nM−1, respectively. An electrochromic molecular imprinted polymer sensor was constructed by electropolymerization of IrO 2 as an electrochromic material on an indium tin oxide glass substrate and electrosynthesis on this electrode was achieved with pyrrole as a functional monomer in the presence of acetamiprid as a template. With the designed electrochromic MIP sensor, it was aimed to detect the color change of the electrochromic material with change in the acetamiprid concentration by the naked eye and to develop a selective pesticide sensor by molecular imprinted polymer technology. These optical characteristics of MIP/IrO 2 /ITO were determined with different acetamiprid concentrations for quantitative analysis by in-situ spectroelectrochemical measurements. The sensor performance of MIP/IrO 2 /ITO was determined with differential pulse voltammetry between −0.2 V and + 0.8 V (vs Ag/AgCl in 0.1 M phosphate buffer solution. MIP/IrO 2 /ITO electrode exhibited linear response with acetamiprid concentrations in the range of 4.29–38.6 nM with a detection limit of 2.72 nM, sensitivity of 47.2 μA nM−1 and reproducibility of 0.87 %. [ABSTRACT FROM AUTHOR]

A highly sensitive aptamer electrochemical sensor based on hydroxylated black phosphorus /thionine/poly- l -lysine (hBP/TH/PLL) nanocomposite and Au nanoparticles (Au NPs) was herein introduced for detection of Acetamiprid. The hBP/TH/PLL nanocomposite was prepared through the capping effect of thionine and adhesion property of poly- l -lysine (PLL). The nanocomposite can maintain excellent electrical conductivity of black phosphorus and effectively prevent oxidation of black phosphorus. The sensor was based on hBP/TH/PLL composite and AuNPs, and used highly specific aptamers as sensor probes. It has advantages such as low detection limit, high selectivity, great repeatability and stability. Under optimum conditions, the linear range of aptamer electrochemical sensor is 10 fM to 1 μM and detection limit is 9.407 fM. The aptamer electrochemical sensor has great selectivity and anti-interference, and has a potential application prospect in the field of rapid trace detection of pesticide residues. [ABSTRACT FROM AUTHOR]

This study proposed a novel method to combine modified carbon nitride (MCN) and tungstophosphoric acid (HPW). First, carbon nitride (CN), containing more uncondensed amino and carbonyl groups, was prepared by thermal condensation from urea at a low temperature. Then, in the presence of formic acid, a reversible nucleophilic addition reaction was performed between the carbonyl groups of formaldehyde (or CN) and amino groups of CN. Subsequently, during the HPW impregnation, the reverse reaction occurred, which increased the HPW loading. The results of the XPS and FTIR analyses verified the occurrence of a nucleophilic addition reaction during the formaldehyde treatment, as well as the formation of hydroxyl functional groups in the intermediate products. After impregnation with HPW, the disappearance of the hydroxyl groups and the recovery of the carbonyl groups were observed in the XPS C1s spectra. The as-prepared MCN450/HPW, obtained by modifying CN450 (CN calcined at 450 °C) with formaldehyde and loading with HPW, exhibited excellent visible-light (λ > 400 nm) photocatalytic degradation of imidacloprid and acetamiprid. The degradation rate constant (0.70 h−1) of imidacloprid was 6.4 times that of CN450, while the degradation rate of acetamiprid by MCN450/HPW was 11 times that of CN450. The results of the active species capture experiments showed that OH and h+ were the main active species in the visible-light photocatalytic degradation process. Unlabelled Image • Nucleophilic addition reaction directed the load of HPW on carbon nitride. • The structure and morphology of as-prepared photocatalysts were characterized. • Hybrid photocatalyst showed high visible light catalytic degradation activity. • The mechanism of photocatalytic degradation reaction was explored. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides (NNIs) are extensively used insecticides worldwide, yet the data on NNIs residues in the Yangtze River, China is scarce. Occurrence and distribution of six NNIs and a metabolite (desmethyl-acetamiprid) in surface water were investigated in the central Yangtze River, China at 20 sites from March to July and September 2015. Acetamiprid (ACE), imidacloprid (IMI) and thiamethoxam (THM) were the most frequently detected NNIs and IMI had a highest median concentration of 4.37 ng/L, followed by ACE (2.50 ng/L), THM (1.10 ng/L), nitenpyram (NTP; 0.34 ng/L), clothianidin (CLO; 0.10 ng/L), and thiacloprid (THCP; 0.02 ng/L). Significantly higher concentrations and detection frequencies of NNIs were observed in the summer than in the spring, which may be explained by the heavier precipitation in summer. Spatial variation with higher levels among the lower sites than the upper sites may be related with the agriculture land use. NNI contamination presented a low risk to aquatic life according to the risk quotient method, while IMI had potential risk to aquatic life according to the threshold of IMI (8.3 ng/L) in freshwater recommended in Netherland. Using the relative potency factors method for chronic cumulative risk assessment for NNIs, potential exposure to NNIs through water ingestion are three orders of magnitude lower than the recommended relative chronic reference dose. Ongoing environmental monitoring of NNIs is needed due to the increase use of NNIs in China. Image 1 • Six typical NNIs were found in the central Yangtze River, and ACE, IMI and THM were the highest. • DM-ACE was found in surface water for the first time. • Higher NNIs levels were found in the summer than in the spring, with the highest observed in June. • Spatial variations of neonicotinoid contamination were observed. • Potential risk of NNIs to aquatic ecosystem and human were assessed. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides (NNIs) are emerging insecticides compared to organophosphates and pyrethroids. Their occurrence in the environment is not well documented in China. In this study, raw water samples (n = 20), finished water samples (n = 20), and tap water samples (n = 165) originating from the Han River and the Yangtze River in Wuhan, Central China, were collected during 2018 for the determination of the NNI residues. NNIs were found in all raw water samples with a median sum concentration of 27.7 ng/L (range: 13.4–186 ng/L). Higher concentrations of NNIs were found in July than in May, and higher NNIs were found in the Han River than in the Yangtze River. Most NNIs were not effectively removed during water treatment, except for acetamiprid and thiacloprid which decreased by 40.1% and 20.0%, respectively. At least three NNIs were detected in all tap water samples with the highest sum concentration of NNIs observed in July (median: 96.2 ng/L, range: 16.7–138 ng/L) among the studied months (median: 15.4, range: 2.59–138 ng/L). The estimated daily intake of NNIs via tap water ingestion in July was 8.66 ng/kg body weight/day for infants, about 4 times higher than that for adults. The concentrations observed in tap water are elevated in China relative to previous studies that were conducted in the USA and in Canada. This is the first study reporting residue levels of NNIs in China. Unlabelled Image • Neonicotinoid insecticides are ubiquitous. • IMI, ACE, DM-ACE, and THM were found in all the raw, finished and tap waters. • NNIs were not apparently removed except for ACE and THCP (about 40% and 20% removal). • NNIs were found in the tap water at highest levels in July. • ACE, DM-ACE, DNT, THCP and NTP were found in tap water for the first time. [ABSTRACT FROM AUTHOR]

• Phanerochaerte chrysosporium could degrade ACET. • A fungal cytochrome P450 which involved in this degradation was identified. • Two ACET metabolites were determined and metabolic pathway was proposed. We previously reported that cytochrome P450 s play critical roles in neonicotinoid insecticide biodegradation by white-rot fungi. Here, we investigated the biodegradation of acetamiprid (ACET) by Phanerochaete chrysosporium to identify the cytochrome P450 involved in this degradation process. During a 20-day incubation period, P. chrysosporium degraded 21% and 51% of ACET in ligninolytic and nonligninolytic media, respectively. The degradation rate of ACET was markedly decreased by the addition of cytochrome P450 inhibitors. Recombinant cytochrome P450s in P. chrysosporium (PcCYP) were heterologously expressed in Saccharomyces cerevisiae strain AH22, and the PcCYP involved in ACET degradation was identified. The results showed that CYP5147A3 can degrade ACET, and two ACET metabolites, N' -cyano- N -methyl acetamidine and 6-chloro-3-pyridinemethanol, were identified. To the best of our knowledge, this study provides the first characterization of the fungal cytochrome P450 that is responsible for the degradation and detoxification of ACET. [ABSTRACT FROM AUTHOR]

Abstract A label-free and enzyme-free aptasensor for sensitive assay of acetamiprid has been established using AT-rich double-stranded (ds) DNA-templated copper nanoparticles (CuNPs) as fluorescent probe. In this work, two hairpin DNA, HP1 and HP2, were elaborately designed with AT-rich DNA sequences in their loops. The aptamer of acetamiprid was located at the 3′-terminal of HP1, which was caged in the stem of HP1. Upon the addition of acetamiprid, the aptamer could combine with acetamiprid to form a target/aptamer complex, and thus its free 5′-terminal was released. Subsequently, the protruded 3′-terminal of HP2 could hybridize with the free 5′-terminal of HP1 to form a stable AT-rich dsDNA. When it interacted with Cu2+ and ascorbic acid (AA), the AT-rich dsDNA/CuNPs were generated with strong fluorescence, offering a "switch-on" detection of acetamiprid. The developed strategy could high selectively detect acetamiprid at the concentration as low as 2.37 nM. Moreover, the possibility of this strategy for the food sample analysis was also investigated. The obtained results demonstrate that the developed strategy has a promising application potential for acetamiprid assay in food safety fields. Graphical abstract fx1 Highlights • A new aptasensor using AT-rich dsDNA-templated copper nanoparticles as fluorescent probe was developed for assay of acetamiprid. • The aptasensor exhibited the advantages of simplicity and low cost, since just two non-labeled two hairpin DNA probes were used in this strategy. • The developed aptasensor exhibited its potential application in food safety field as verified by the conducted assay in vegetable extract. [ABSTRACT FROM AUTHOR]

The potentiality of eco-friendly low cost natural and agricultural wastes of orange peels (OPAC) and almond shells (ASAC) prepared for the removal of acetamiprid pesticide from aqueous solution has been investigated in batch experiments. Structure and morphology of OPAC and ASAC were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), Field Emission scanning electron microscopy equipped with an energy dispersive x-ray analyzer (SEM-EDX) and surface area (BET) was determined by the nitrogen adsorption and desorption isotherm. The effect of various physicochemical parameters such as initial acetamiprid concentrations, adsorbent dose and contact time has been studied. The percent removal of acetamiprid onto OPAC and ASAC were 99.46 and 99.45% from aqueous solutions. The adsorption process was attained an equilibrium within 120 min of contact time. The experimental isotherms data were analyzed using Freundlich, Langmuir, and Dubinin-Radushkvich (D-R) isotherm equations. Results showed that adsorption isotherms of acetamiprid onto OPAC and ASAC can be slightly better- fitted data by the Freundlich model than Langmuir model. The maximum adsorption capacities were 151.515 and 370.37 mg g-1 for OPAC and ASAC, respectively. The energy of adsorption for OPAC and ASAC were 0.791 and 0.845 KJ/mol, indicating that the adsorption process is physical in nature. The kinetic adsorption of acetamiprid was fitted well the pseudo-second-order kinetic model for OPAC and ASAC, respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Yb-doped PbO 2 electrode were prepared by electrodeposition methods. • The addition of Yb can enhance the stability and electrochemical activity of PbO 2 electrode. • Electrocatalytic degradation of acetamiprid was investigated by Yb-doped PbO 2 anode. • The intermediates were identified and oxidation mechanism of acetamiprid was elucidated. • The Yb-doped PbO 2 electrode is promising anode material for pollutants degradation. Abstract The Yb-doped PbO 2 electrodes were fabricated by electrodeposition method. SEM and XRD experiments revealed that the adulteration of Yb can decrease the crystal grain size and make the electrodes more compact. Electrochemical measurements, accelerated service lifetime and bulk electrolysis experiments proved that Yb-doped PbO 2 electrodes had higher oxygen evolution overpotential, stability and acetamiprid removal ratio than pure PbO 2 electrodes. The effect of operating parameters, such as current density, initial acetamiprid concentration, and pH value, on the electrocatalytic degradation of acetamiprid were systematically studied. The electrocatalytic oxidation reaction of acetamiprid on Yb-doped PbO 2 electrodes was highly effective, which obeyed the pseudo-first-order kinetics model. Intermediates analysis and electrocatalytic degradation mechanism of acetamiprid by Yb-doped PbO 2 electrodes were implemented, and the degradation pathways were divided into three different sub-routes due to three function groups on acetamiprid initially attacked by hydroxyl radicals. Finally, all the byproducts were decontaminated into CO 2 and H 2 O. These results proved that Yb-doped PbO 2 electrodes have more promising application potential for the electrocatalytic degradation of refractory organic pollutants. [ABSTRACT FROM AUTHOR]

Abstract A molecularly imprinted polymer (MIP) on silane-doped carbon dots (Si-CDs) has been synthesized as a novel optical sensor for selective detection of acetamiprid (ACT). Highly fluorescence Si-CDs have been first prepared by hydrothermal method. Subsequently, MIP has been formed on the surface of Si-CDs (MIP@Si-CDs) by a sol-gel process. The properties and structure of the Si-CDs and MIP@Si-CD nanocomposites have been characterized by fluorescence spectroscopy, UV–Vis absorption spectroscopy, transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and X-ray diffraction techniques. Various parameters, which affect the optical signal, have been optimized. The fluorescence signal of MIP@Si-CDs showed linear response with ACT concentration in the 7–107 nM range with a detection limit of 2 nM and a precision of 2.7% and 3.3% for five replicate detections of 17 and 33 nM ACT under optimal conditions. In addition, the sensor has been satisfactorily utilized for the detection of ACT content in real samples. Graphical Abstract Unlabelled Image Highlights • A novel optical sensor for the detection of acetamiprid was developed. • Fluorescence quenching mechanism was accrued with increasing acetamiprid. • The optical sensor was characterized with 2 nM detection limit for acetamiprid. • The linear dynamic range of the sensor for acetamiprid comprised 7–107 nM. [ABSTRACT FROM AUTHOR]

Abstract In present work, a versatile "signal-on" electrochemical aptasensor with ultra-sensitivity and high selectivity for detecting acetamiprid residues has been successfully constructed. Electrochemistry behaviors of as-synthesized copper-centered metal-organic frameworks (CuMOF) on various electrodes were investigated in details. The results indicated that CuMOF exhibited well-behaved redox events. Thus, we used Au-CuMOF as signaling element to label probe DNA (pDNA). The gold nanoparticles-reduced graphene oxide (Au-rGO) has a high specific surface area and excellent conductivity, which was utilized to immobilize complementary strand (cDNA). In the presence of acetamiprid, Au-CuMOF-labeled pDNA would hybridize with the exposed cDNA, allowing CuMOF to approach the electrode and produce a sensitive signaling current. Such a "signal-on" method does not suffer from the drawbacks of "signal-off" methods. The linear range of this proposed electrochemical aptasensor was 0.1 pM–10.0 nM and the detection limit was as low as 2.9 fM. This platform exhibited wonderful selectivity, stability, and repeatability, and was successfully applied to detect acetamiprid residues in tea samples exhibiting enormous practical application potential. Graphical abstract Image 1 Highlights • A signal-on electrochemical acetamiprid aptasensor was fabricated. • CuMOF was prepared and used as a signaling element of aptasensor. • DNA reactions were ingeniously designed to improve the sensitivity. [ABSTRACT FROM AUTHOR]

Abstract Seeking alternatives for alkylphenol ethoxylates (APEOs) have been a heavily researched topic in the surfactant industry and agricultural systems. In this study, the combined effects of different ethoxylates and pesticides on the bioactivity against three pests and toxicological risks to Daphnia magna were investigated. Results showed that alcohol ethoxylates (AEOs) had higher synergistic effects on the bioactivity of pesticides against Spodoptera exigua , Agrotis ipsilon and Aphis citricola than did APEOs. In terms of the joint toxicity of the ethoxylates and pesticides to D. magna , additive index method, toxicity unit method, V value method and isobologram method were used in the tests. All of these methods indicated that the joint effects of APEOs + acetamiprid and APEOs + indoxacarb upon D. magna turned from synergism to antagonism with the increasing EO (ethylene oxide) numbers. Those of AEOs exhibited similar trends. Overall, AEOs may be potential alternatives for APEOs in agriculture as they synergize pesticides against three pests significantly more than do APEOs. However, further research should investigate the compounds' environmental risks to aquatic organisms because the AEOs were highly toxic to D. magna. Graphical abstract Unlabelled Image Highlights • AEOs had higher synergistic effects on pesticides than APEOs. • Additive index, toxicity unit, V value and isobologram methods were integrated. • Synergistic ratios and toxicities of AEOs and APEOs decreased with the EO numbers. • AEOs may be potential alternatives for APEOs in agricultural production system. [ABSTRACT FROM AUTHOR]

[Display omitted] • First illustration of degradation of acetamiprid using HC based combined strategies. • Optimization of operating parameters has intensified the cavitational effect. • Circular venturi shows better performance than orifice plate. • HC + photo-Fenton process using circular venturi is the most competent approach. • Identified five degradation by-products of acetamiprid using LC-MS/MS analysis. Degradation of acetamiprid (neonicotinoid group of pesticide) has been intensified by the application of hydrodynamic cavitation (HC) in combination with Fenton and photo-Fenton process using orifice plate and circular venturi as a cavitating device. Optimization of operating parameters using circular venturi has resulted in the optimum pH of 3 and the optimum acetamiprid concentration of 10 ppm. The inlet pressure to the cavitator was optimised at 5 bar for orifice plate and 6 bar for circular venturi. The molar ratio of acetamiprid to hydrogen peroxide and Fe2+ ions to H 2 O 2 was optimised at 1:10 and 1:30 respectively. HC based combined strategies using circular venturi have resulted in the intensification of rate of degradation of acetamiprid. The reaction rate constant of 3.35 × 10-3 min−1, 4.80 × 10-3 min−1 and 16.17 × 10-3 min−1 with synergistic coefficient of 4.16, 1.78 and 1.39 was obtained in case of HC in combination with H 2 O 2 , Fenton's reagent and photo-Fenton process respectively. Circular venturi has witnessed higher rate of degradation of acetamiprid as compared to orifice plate in case of HC and HC based combined strategies. Degradation by-products of acetamiprid produced during HC + photo-Fenton process have been identified successfully using LC-MS/MS analysis and the degradation mechanism has been proposed. [ABSTRACT FROM AUTHOR]

Ensifer adhaerens CGMCC 6315 contains two nitrile hydratases, CnhA and PnhA, which both convert the neonicotinoid insecticide acetamiprid to its amide metabolite. Here, we report that upregulation of PnhA and CnhA expression is related to nitrogen metabolism. Proteomic analysis showed that general nitrogen regulation protein NtrC was upregulated under nutrient deprivation. We thus constructed a Δ ntrC mutant strain of E. adhaerens CGMCC 6315. In the Δ ntrC strain, when cells were cultured in minimal salts medium supplemented with ammonium chloride, acetamiprid degradation and the expression of cnhA and pnhA were enhanced relative to those in wild-type E. adhaerens CGMCC 6315. In addition, NtrC negatively regulates synthesis of extracellular polysaccharides in this bacterium. The germination rate of soybean seeds was improved by inoculation with the Δ ntrC strain of E. adhaerens CGMCC 6315 compared with the wild-type. This study is the first to report regulation of the expression of nitrile hydratase by NtrC, which is important for the practical remediation of pesticide pollution. [Display omitted] • General nitrogen regulation protein NtrC regulating the expression of nitrile hydratase was firstly reported. • NtrC negatively regulates extracellular polysaccharide synthesis in Ensifer adhaerens CGMCC 6315. • The NtrC mutant of Ensifer adhaerens CGMCC 6315 has higher ability to degrade acetamiprid and promote plant growth. [ABSTRACT FROM AUTHOR]

A label-free SERS sensor was successfully developed for simultaneous detection of acetamiprid and thiram using easily synthesized bimetallic core-shell Au@Ag nanoparticles. Au@Ag nanoparticles synthesized by a seed-mediated growth method were used as SERS substrates to realize simultaneous detection of mixed pesticides according to the SERS intensity at 635 (acetamiprid) and 1385 (thiram) cm−1. Complex mixed pesticide systems were established to research the feasibility of simultaneous detection of this SERS sensor. The method showed satisfactory linearity in the range of 5–100 μM and 0.5–10 μM with the limit of detection of 1.22 μM and 0.076 μM for acetamiprid and thiram in apple juice samples, respectively. The recovery for accuracy and precision analysis was 90.2–122.12% in apple juice samples. This SERS detection method combined with portable Raman spectrometer will become a powerful tool for simultaneous testing of multiple contaminants in food safety on-site detection. • A label-free SERS sensor realized simultaneous detection of thiram and acetamiprid. • Core-shell Au@Ag NPs was prepared as SERS enhanced substrates. • Researched SERS signal of pesticide mixture of different proportions. • The results of the sensor indicated high sensitivity and accuracy. • The method can be used for simultaneous testing other multiple risky pollutants. [ABSTRACT FROM AUTHOR]

Multiple pesticides are often used in combination to protect crops from pests. This makes rapid on-site detection of pesticide contamination challenging. Herein, we describe a method for simultaneous detection of diverse neonicotinoid pesticides using a sensor that combines neonicotinoid-specific odorant-binding protein 2 (OBP2), which was cloned from an insect chemical sensing protein and modified gold nanoparticles with local surface plasmon resonance (LSPR)-based digital nanoplasmonometry (DiNM). When neonicotinoid pesticides bind to OBP2 on gold nanoparticles, the induced LSPR shift peak wavelength is too small to be measured using conventional LSPR immunoassays. DiNM records and compares the scattered image intensity in two adjacent wavelength bands, A and B, centered on the LSPR peak. It considers both the peak shift and the relative intensity change in these two bands, resulting in a significant LSPR signal enhancement. Then the spectral-image contrast was computed as the signal response. Using this approach, we obtained excellent limits of detection (LODs) of 1.4, 1.5, and 4.5 ppb for the neonicotinoids imidacloprid, acetamiprid, and dinotefuran, respectively. Blind tests demonstrated high positive and negative rates for teas, approximately 85 and 100%, respectively. Recombinant OBP2 produced in E. coli offers several advantages over antibodies, including high yield, time savings, and cost effectiveness. Moreover, this method is highly selective and sensitive to neonicotinoids, making it practical for field use. • OBP2 displays a broader affinity for neonicotinoids than monoclonal antibodies. • OBP2 expression is higher yield, saves time, and cost-effective than antibodies. • Spectral image contrast and digital analysis enable LSPR direct pesticide detection. • The direct detection with a LOD of ppb levels within 45 min was reached. • Real sample blind test results were consistent with the standard mass spectrometry. [ABSTRACT FROM AUTHOR]

Solid-phase microextraction (SPME) is a sample pretreatment technique for enrichment of trace level of compounds from complex matrices. The fiber coating, as an extraction phase, is the significant part of SPME, which specifying the analytical performance of the developed SPME. In this study, a novel in situ fabricated Cu@porous carbon fiber that derived from copper benzene-1,4-dicarboxylate framework@pencil graphite (Cu-BDC MOF@PG) fiber was prepared as a SPME fiber. The Cu-BDC MOF was electrodeposited on the surface of pencil graphite. The Cu@porous carbon fiber with nanoporous structure was constructed by the direct carbonization of the electrosynthesized fiber. The Cu@porous carbon fiber showed high analytical performance for direct immersion SPME (DI-SPME) of acetamiprid and imidacloprid in fruit and vegetable samples. The SPME method was coupled by high-performance liquid chromatography-ultraviolet detection (SPME-HPLC-UV) for determination of the analytes. Under the optimized condition, good linear ranges (1–500 μg L−1 and 0.5–200 μg L−1) and acceptable limits of detection (LODs = 0.30 and 0.15 μg L−1), appropriate spiking recoveries in the range 87–109.0% were attained for acetamiprid and imidacloprid, respectively. Intra- and inter-day relative standard deviations were found within the ranges of 2.35–3.46% and 3.30–3.70%, respectively. These results signify promising potential of the in situ fabricated porous carbon fiber for SPME applications. Considering that most of the pencil graphite is made of carbon, after the carbonization of the Cu-BDC MOF@PG fiber, a unified porous carbon fiber is obtained. Compared to other reported procedures, in situ direct carbonization of Cu-BDC MOF@PG fiber was a one-step and straightforward method to fabricate carbon fiber. [Display omitted] • Cu-MOF was electrodeposited on pencil graphite substrate • Cu@porous carbon fiber prepared by direct carbonization of the Cu-MOF@Pencil graphite fiber • The fabricated fiber was used as a cost-effective and high efficient sorbent for SPME • The SPME-HPLC-UV used for analysis of acetamiprid and imidacloprid in real samples [ABSTRACT FROM AUTHOR]

• A novel Strep-Tag system integrated apta-magnetic sorbent was prepared. • The integration of the Strep-tag system frees the elution from organic solvents. • The sorbents are highly stable, selective, and regenerative. • The sorbents exhibit good application prospects for MSPE from complex matrix. • The developed MSPE method has comparable performance to previous studies. A novel magnetic sorbent, named ABA-(Strep-tag II)-STMB, was prepared by modifying the acetamiprid-binding aptamer (ABA) onto Strep-Tactin-coated magnetic beads (STMBs) via Strep-tag II. The integration of the Strep-tag system allows the elution of the target by the addition of D-biotin, which can compete with Strep-tag II for the Strep-Tactin sites on the magnetic beads, instead of organic solvents. The sorbent showed good selectivity and reusability, and the extraction efficiency could still reach 90.5 % after 8 reuses. Under the optimized conditions, the developed magnetic solid-phase extraction (MSPE) method exhibited good linearity in the range of 0.1–100 μM, with the limits of detection (LOD) of 0.017–0.019 μM, and the limits of quantification (LOQ) of 0.057–0.066 μM. The relative standard deviations (RSDs) were below 5.51 %. The spiked recoveries were 84.4 %–96.0 %. The analysis results were in good agreement with those of the QuEChERS method. [ABSTRACT FROM AUTHOR]

[Display omitted] • An advanced nanomaterial-Fe-N-C SAzymes with distinct oxidase-like activity was applied in Aptasensor. • Thiol-modified aptamers could significantly dampen the oxidase-like activity of Fe-N-C SAzymes. • A Fe-N-C SAzymes-based aptasensor was developed to detect acetamiprid. • with high sensitivity and selectivity. • The developed Fe-N-C SAzymes-based aptasensor was successfully applied to detect acetamiprid spiked in river water. Acetamiprid (Ace), extensively employed in agricultural production as a substitute for organophosphorus pesticides, poses a potential threat to the environment and human health due to excessive residues. Hence, the development of reliable and convenient techniques to determine Ace levels in the environment holds significant importance. Among various assay methods, nanomaterial-based aptamer-based biosensors (aptasensors) have emerged as efficient and promising tools. In this study, we successfully developed a novel aptasensor for monitoring Ace in the environmental water, utilizing advanced nanomaterials known as Fe-N-C single-atom nanozymes (SAzymes). Fe-N-C SAzymes exhibited excellent catalytic activity, high stability, and complete atom utilization. A facile dual-confinement route was employed for the synthesis of Fe-N-C SAzymes, and their performance as oxidase-like nanozymes was investigated. The synthesized Fe-N-C SAzymes presented distinct oxidase-like activity and demonstrated the capability to interact with a chromogenic indicator-TMB, serving as the signal transduction element in our assay. Furthermore, we found that thiol-modified aptamers could effectively dampen the oxidase-like activity of Fe-N-C SAzymes.Therefore, we successfully developed a Fe-N-C SAzymes assisted detection method for Ace, which exhibited high sensitivity (LOD = 16.9 nM) and selectivity. Overall, this work provides new insights into the design of multifunctional Fe-N-C SAzymes for environmental and biological applications. [ABSTRACT FROM AUTHOR]

The aim of this research is to study the feasibility of using low-cost and natural bentonite and kaolinite clays, compared with commercial bentonite, as raw materials to prepare catalysts for the removal of two emerging pollutants, the neonicotinoid pesticides nitenpyram and acetamiprid, by heterogeneous Fenton process. The raw materials were subjected to a simple ion exchange method to improve their textural properties using a solution containing ferric cations followed by calcination at 500 °C. Results show high activity for all the catalysts in the removal of these pesticides, Stability tests were carried out confirming the high stability of these materials. • Homemade catalysts based on iron-exchanged clays have been economically prepared. • The materials showed high catalytic activity for the removal of pesticides by CWPO. • The increase in the reaction temperature improved the conversion of the pollutants. • Leaching of iron in all cases was very low confirming the heterogeneous process. [ABSTRACT FROM AUTHOR]

Acetamiprid (ACT) is used extensively in agriculture worldwide, although data on ACT concentrations in natural water bodies and its impact on aquatic organisms are limited. To study whether ACT influences the embryogenesis of the South African clawed frog Xenopus laevis , embryos were incubated in ACT solutions from 0.01 to 100 mg/L. The low concentrations were chosen on the basis of concentrations already found in nature. ACT treatment leads to shorter embryo lengths, intestine malformation and reduced eye areas. It also affects the cranial cartilage and cardiac development as well as the embryo's mobility. The expression of tissue-specific marker genes is affected as well. Thus, our study suggests that pesticides may lead to an increased mortality of non-target organisms and emphasizes the importance of regular testing for ACT concentrations in nature. Our study provides an overview of ACT effects and can therefore be used as a basis for an ACT risk assessment. • ACT leads to morphological defects and impaired organ development. • ACT increases heartrate. • ACT reduces mobility. • ACT impairs the expression of the NCC marker gene egr2 and the heart specific gene mhcα. [ABSTRACT FROM AUTHOR]