-
Bioelectrochemistry (Amsterdam,... Dec 2022In this work, an interference-resistant electrochemical aptasensor that could detect profenofos in vegetables was constructed based on complexes of graphene oxide and...
In this work, an interference-resistant electrochemical aptasensor that could detect profenofos in vegetables was constructed based on complexes of graphene oxide and polyaniline (GO@PANI) and gold nanoparticles-tetrahedral DNA nanostructure (Au-TDN). Compared with a single chain aptamer, the tetrahedral DNA nanostructure is highly stable and allows the aptamer on this structure to stand in a highly ordered position on an electrode surface. Moreover, the AuNPs are biocompatible and can protect the activity of the aptamer, which can improve the assembly success rate of Au-TDN. Besides, the conductivity of PANI had been tremendously enhanced thanks to the existence of GO, which improved the dispersion of PANI. The GO@PANI was prepared by a chemical synthesis method, which had a large surface area and was able to adsorb many Au-TDN. Under optimal working parameters, the constructed aptasensor exhibited good electrochemical sensing performance with a detection limit of 10.50 pg/mL and a linear range of 1.0 × 10-1.0 × 10 pg/mL. In addition, it was employed in detecting profenofos in vegetables with a good recovery rate of 90.41-116.37 %. More importantly, the aptasensor also has excellent stability and high selectivity. This study provides a promising method to avoid interference in the detection of profenofos by sensors.
Topics: Aniline Compounds; Biosensing Techniques; DNA; Electrochemical Techniques; Gold; Graphite; Metal Nanoparticles; Nanostructures; Organothiophosphates
PubMed: 35973324
DOI: 10.1016/j.bioelechem.2022.108227 -
The Analyst Sep 2022In this work, a simple, sensitive and selective colorimetric method was established for the detection of profenofos. Firstly, novel flower-shaped AuPtRh trimetallic...
In this work, a simple, sensitive and selective colorimetric method was established for the detection of profenofos. Firstly, novel flower-shaped AuPtRh trimetallic nanospheres were synthesized a simple one-pot method, and had outstanding peroxidase catalytic activity. AuPtRh nanospheres with a great specific surface area were linked with an aptamer Au-S and Pt-S bonds to specifically recognize profenofos. A graphene oxide grafted stainless-steel mesh (SSM-GO) was prepared to be a carrier and the aptamer-AuPtRh was nonspecifically adsorbed on the surface of SSM-GO, which was to be the capture probe for the detection of profenofos in real samples. They were characterized and confirmed by transmission electron microscopy, atomic force microscopy, . Through the investigation of the catalytic performance on the basis of the Michaelis equation, the of AuPtRh nanospheres was 22.27 × 10 M s, and was 0.6632 mM, which indicated that the affinity of AuPtRh nanospheres was relatively higher than that of horseradish peroxidase and Au NPs. In the presence of profenofos, the aptamer-AuPtRh would specifically combine with profenofos, which would further detach from SSM-GO. Then, it was introduced into the 3,3',5,5'-tetramethylbenzidine/HO (TMB/HO) system to form blue oxTMB. The linear range of this colorimetric biosensor was 1-300 ng L and the limit of detection was 0.725 ng L. It also had good recovery and anti-interference ability in real samples, which provided a new strategy for the rapid detection of pesticides.
Topics: Biosensing Techniques; Colorimetry; Hydrogen Peroxide; Oligonucleotides; Organothiophosphates
PubMed: 35968735
DOI: 10.1039/d2an00668e -
Sensors (Basel, Switzerland) Jul 2022In this work, we reported a rapid and sensitive fluorescence assay in homogenous solution for detecting organophosphorus pesticides by using tetramethylrhodamine...
In this work, we reported a rapid and sensitive fluorescence assay in homogenous solution for detecting organophosphorus pesticides by using tetramethylrhodamine (TAMRA)-labeled aptamer and its complementary DNA (cDNA) with extended guanine (G) bases. The hybridization of cDNA and aptamer drew TAMRA close to repeated G bases, then the fluorescence of TAMRA was quenched by G bases due to the photoinduced electron transfer (PET). Upon introducing the pesticide target, the aptamer bound to pesticide instead of cDNA because of the competition between pesticide and cDNA. Thus, the TAMRA departed from G bases, resulting in fluorescence recovery of TAMRA. Under optimal conditions, the limits of detection for phorate, profenofos, isocarbophos, and omethoate were 0.333, 0.167, 0.267, and 0.333 µg/L, respectively. The method was also used in the analysis of profenofos in vegetables. Our fluorescence design was simple, rapid, and highly sensitive, which provided a means for monitoring the safety of agricultural products.
Topics: Aptamers, Nucleotide; DNA, Complementary; Fluorescence; Organophosphorus Compounds; Pesticides
PubMed: 35957269
DOI: 10.3390/s22155712 -
Talanta Jan 2023The traditional preparation of MXeneTiC is complicated. Two-dimensional MXeneTiC nanosheets were prepared via in-situ generation of HF etching TiAlC under the microwave...
The traditional preparation of MXeneTiC is complicated. Two-dimensional MXeneTiC nanosheets were prepared via in-situ generation of HF etching TiAlC under the microwave irradiation. Gold nanocluster doped nanosheets sol (MXene@Au) with excellent stability and strong catalysis was synthesized with no product residue reducer CO. MXene@Au nanosol can catalyze mandelic acid-HAuCl to produce gold nanoparticles, which can be traced via resonance Rayleigh scattering (RRS) and surface-enhanced Raman scattering (SERS). Coupled the dual-mode nanocatalytic indicator reaction with aptamer reaction, a high sensitivity, selectivity, facile SERS/RRS dual-mode biosensnoring assay platform has been constructed for isocarbophos (ICP). The linear range of SERS was 1.0 × 10-2.5 × 10 nmol/L, with a detection of limit 4.5 × 10 nmol/L (S/N = 3). It has been used to detect ICP in water samples, with a good recovery (95.5-104%) and a good relative standard deviation (5.2-9.6%). This new nanocatalytic amplification biosensoring strategy can also assay other organic pesticides including malathion, glyphosate, profenofos and carbendazim. In addition, the nanocatalytic mechanism was investigated.
Topics: Catalysis; Gold; Malathion; Metal Nanoparticles; Oligonucleotides; Pesticides; Spectrum Analysis, Raman; Water
PubMed: 35952500
DOI: 10.1016/j.talanta.2022.123771 -
The Science of the Total Environment Oct 2022An ultrasensitive electrochemiluminescence (ECL) aptasensor for detection of profenofos was constructed by the reducibility and chemiluminescence property of...
An ultrasensitive electrochemiluminescence (ECL) aptasensor for detection of profenofos was constructed by the reducibility and chemiluminescence property of N-(aminobutyl)-N-(ethylisoluminol) (ABEI). ABEI was used to reduce silver nitrate (AgNO) to silver nanoparticles (AgNPs), which could be adsorbed on the lattice of graphene oxide (GO) to form ABEI-AgNPs-GO complex. This compound could achieve excellent luminescence. The aptamer (Apt) modified (5') by sulfhydryl groups could be immobilized on AgNPs to capture profenofos. When profenofos was present, the ECL signal of the aptasensor would be weakened. To further demonstrate the successful construction of the aptasensor, cyclic voltammetry tests were performed on an electrochemical workstation and an ECL analyzer, respectively. The standard curve and specificity experiment both showed that the sensor had the advantages of low limit of detection (LOD) and good specificity. Under the optimal conditions, the aptasensor had a good linear response for profenofos in the range of 1 × 10-1 × 10 ng/mL. It also had a LOD of 6.7 × 10 ng/mL and a correlation coefficient (R) of 0.9991. The aptasensor had been successfully applied to the detection of profenofos in vegetables. The recovery range of the proposed ECL aptasensor was 98 % ~ 107.4 %.
Topics: Biosensing Techniques; Electrochemical Techniques; Gold; Limit of Detection; Luminescent Measurements; Luminol; Metal Nanoparticles; Organothiophosphates; Silver
PubMed: 35803425
DOI: 10.1016/j.scitotenv.2022.157184 -
Environmental Monitoring and Assessment Jun 2022The presence of pesticide residues in agricultural products is posing serious health concerns for consumers. This study monitored the concentrations of pesticide...
The presence of pesticide residues in agricultural products is posing serious health concerns for consumers. This study monitored the concentrations of pesticide residues in some selected fruit and vegetables, and their potential health risks were also assessed. Organochlorine (OCPs) and organophosphate (OPPs) residues were extracted and quantified with a gas chromatography-pulsed flame photometric detector. A total of 38 pesticide residues were identified and the results showed mean concentration (mg/kg fresh weight) of (OCPs) residues ranging from 0.02 to 0.37 and (OPPs) residues ranging from 0.01 to 0.33. The concentrations (mg/kg) of isodrin, heptachlor, dicofol, prothiophos, profenofos and dichlorvos were above the maximum residue limit. The non-carcinogenic health risk estimates revealed a possible potential health risk from consumption of the fruits and vegetables in adults and children for most of the pesticide residues. The cancer risk assessment estimates gave values below 10 which suggests no probable cancer risk. As a result of the increasing trend in pesticide use in Nigeria, routine monitoring of pesticide residues in agricultural produce is a necessity to ensure the safety of consumers.
Topics: Child; Environmental Monitoring; Food Contamination; Fruit; Humans; Neoplasms; Nigeria; Organophosphates; Pesticide Residues; Vegetables
PubMed: 35731304
DOI: 10.1007/s10661-022-10139-z -
Food Chemistry Nov 2022Colorimetric and fluorescent sensors were developed for the detection of profenofos. The colorimetric assay relied on the aggregation of cysteine modified gold...
Colorimetric and fluorescent sensors were developed for the detection of profenofos. The colorimetric assay relied on the aggregation of cysteine modified gold nanoparticles (Au-cys) composite caused by the hydrogen bond and Au-S bond between profenofos and Au-cys. The further addition of S, N-doped carbon quantum dots (CDs) (fluorescence quantum yield up to 98%) into the Au-cys system depended on the change of fluorescence intensity of Au-cys-CDs owing to the inner filter effect between Au-cys and CDs. Under the optimal conditions, the sensor exhibits good linearity within 0.2-1.2 mg L and 20-320 μg L, and limit of detection of 21.7 μg L and 5.5 μg L in colorimetry and fluorescence mode, respectively. The developed sensor did not only possess favorable selectivity and sensitivity, but also feasibility of usage in the actual detection of profenofos in farmland system samples.
Topics: Carbon; Colorimetry; Cysteine; Farms; Fluorescent Dyes; Gold; Limit of Detection; Metal Nanoparticles; Organothiophosphates; Quantum Dots
PubMed: 35653988
DOI: 10.1016/j.foodchem.2022.133321 -
Chirality Aug 2022While not initially a focus or priority, in recent decades, an emphasis has been placed on the activity of individual enantiomers of widely used pesticides. Of...
While not initially a focus or priority, in recent decades, an emphasis has been placed on the activity of individual enantiomers of widely used pesticides. Of particular note are organophosphorus-based pesticides like fenamiphos and profenofos, as examples. This work explores the enantioselective high-performance liquid chromatography (HPLC) separations of seven such organophosphorus pesticides (OP's) on the library of immobilized polysaccharide-based chiral stationary phases (CSPs) with normal phase hexane/alcohol mixtures. Further exploration of the effect of mobile phase strength and temperature on several of the separations was performed using simple factorial design. Equivalent retention of the first eluting enantiomer of several combinations of temperature and mobile phase was compared for peak shape, selectivity, and resolution. Similarly, equivalent selectivity of several combinations of temperature and mobile phase was compared for peak shape, retention of the first eluting enantiomer, and resolution. The results of this study make available several new chiral separations of the OPs included in the work that were not previously documented, including separations on the three most recently commercialized phases, Chiralpak IH, IJ, and IK. Additionally, sufficient understanding was obtained to be able to predict the trade-off of resolution, analysis time, peak sharpness (and thus improve limit-of-detection [LOD]/limit-of-quantification [LOQ]), robustness, and convenience of conditions for further application optimization.
Topics: Chromatography, High Pressure Liquid; Organophosphates; Organophosphorus Compounds; Pesticides; Polysaccharides; Stereoisomerism
PubMed: 35642080
DOI: 10.1002/chir.23473 -
Journal of the Science of Food and... Nov 2022Ultrasound has the potential to increase microbial metabolic activity, so this study explored the stimulatory effect of ultrasound pre-treatment on the degradation of...
BACKGROUND
Ultrasound has the potential to increase microbial metabolic activity, so this study explored the stimulatory effect of ultrasound pre-treatment on the degradation of four common pesticides (fenitrothion, chlorpyrifos, profenofos, and dimethoate) during milk fermentation by Lactobacillus plantarum and its effect on yogurt quality.
RESULTS
Appropriate ultrasound pretreatment significantly enhanced the growth of L. plantarum. The degradation percentages of pesticides increased by 19-38% under ultrasound treatment. Ultrasonic intensity, pulse duty cycle, and duration time were key factors affecting microbial growth and pesticide degradation. Under optimal ultrasonic pre-treatment conditions, the degradation rate constants of four pesticides were at least 3.4 times higher than those without sonication. In addition, such ultrasound pretreatment significantly shortened yogurt fermentation time, increased the water holding capacity, hardness and antioxidant activity of the yogurt, and improved the flavor quality of the yogurt.
CONCLUSION
Ultrasonic pretreatment significantly accelerated the degradation of the four pesticides during yogurt fermentation. In addition, such ultrasound pretreatment increased the efficiency of yogurt making and improved the quality of yogurt in terms of water holding capacity, firmness, antioxidant activity, and flavor. These findings provide a basis for the application of ultrasound to the removal of pesticide residues and quality improvement of yogurt. © 2022 Society of Chemical Industry.
Topics: Animals; Antioxidants; Chlorpyrifos; Dimethoate; Fenitrothion; Fermentation; Milk; Pesticide Residues; Pesticides; Ultrasonic Therapy; Water; Yogurt
PubMed: 35596658
DOI: 10.1002/jsfa.12028 -
Brazilian Journal of Biology = Revista... 2022Cotton mealybug is a highly invasive pest of agricultural crops worldwide. Major agriculturists most rely on the use of insecticides for the control of pesticides. So,...
Cotton mealybug is a highly invasive pest of agricultural crops worldwide. Major agriculturists most rely on the use of insecticides for the control of pesticides. So, the indiscriminate use of insecticides leads to resistance development in recent years. For this purpose, an experiment was conducted using different concentrations of the three insecticides (profenfos chlorpyrifos and triazophos) to check the hormoligosis effects against cotton mealybug (CMB) in laboratory conditions. Investigation of variations for % mortality of adults of CMB after three days revealed that all treatments had statistically significant (P ˂ 0.05). The highest mortality was observed at the highest concentrations of profenofos 2.4% (38.55%). After 7 days, all the treatments were significant with difference in means (P ˂ 0.05). The highest mortality was recorded at the highest dilution of pesticide profenofos 2.4% (77.11%). The values of fecundity and longevity exposed a valid difference among treatments (P ˂ 0.05). Maximum fecundity was observed at the concentration 2.4% (181.41%) and longevity showed (38.46%). The highest mortality was observed at a concentration of triazophos 4% (27.98%). For chlorpyriphos the highest mortality was examined at concentration 4% (24.79%). The fecundity showed a statistically significant difference for different concentrations of triazophos and chlorpyriphos (P ˂ 0.05). The results of the recent study provide valuable information regarding the selection of insecticides and hormoligosis effects. The study can be helpful in the implications of integrated pest management of P. solenopsis.
Topics: Animals; Chlorpyrifos; Hemiptera; Insecticides
PubMed: 35584406
DOI: 10.1590/1519-6984.261971