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1.
Food Chem X ; 22: 101523, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38911916

ABSTRACT

Engineered bacterial magnetic nanoparticles (BMPs) fused with protein A (BMP-PA) can bind antibodies, creating immunomagnetic beads that offer an attractive tool for targets screening. In the study, BMP-PA-IgG was formed by attaching broad-spectrum monoclonal antibodies against glucocorticoids (GCs) to BMP-PA. Immunomagnetic assay was developed for analysis of GCs, using the BMP-PA-IgG and hydrocortisone-horseradish peroxidase. The developed assay exhibited broad specificity for GCs, including hydrocortisone (HCS), betamethasone (BMS), dexamethasone (DMS), prednisolone (PNS), beclomethasone (BCMS), cortisone (CS), 6-α-methylprednisone (6-α-MPNS), and fludrocortisone acetate (HFCS), with half inhibitory concentrations (IC50) ranging from 0.88 to 6.57 ng/mL. The proposed assay showed average recoveries of HCS and DMS ranging from 75.6% to 105.2% in chicken and pork samples, which were correlated well with those obtained by LC-MS/MS. This study indicated that the integration of engineered immunomagnetic beads into immunoassay systems offer possibilities for the sensitive and selective detection of GCs.

2.
Anal Methods ; 16(12): 1756-1762, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38440844

ABSTRACT

Single-chain variable fragments (scFvs) are valuable in the development of immunoassays for pesticide detection. In this study, scFvs specific to thiamethoxam (Thi) were successfully isolated from a library generated by chicken immunization through heterologous coating selection. These scFvs were subsequently expressed with fusion with an Avi tag and alkaline phosphatase. After combination and optimization, a scFv-biotin based enzyme linked immunosorbent assay (ELISA) was developed for the detection of Thi, demonstrating an impressive half-maximum signal inhibition concentration (IC50) of 30 ng mL-1 and a limit of detection (LOD) of 1.8 ng mL-1. The immunoassay exhibited minimal cross-reactivity with other neonicotinoid insecticides, except for 7.5% for imidacloprid and 6.7% for imidaclothiz. The accuracy of the assay was confirmed by testing spiked samples of apple, pear, cabbage, and cucumber, which resulted in average recoveries ranging between 82% and 119%, closely aligning with the results obtained through high-performance liquid chromatography. Therefore, the chicken scFv-biotin based assay showed promise as a high-throughput screening tool for Thi in agricultural samples.


Subject(s)
Insecticides , Single-Chain Antibodies , Animals , Thiamethoxam , Single-Chain Antibodies/genetics , Single-Chain Antibodies/chemistry , Chickens , Biotin , Insecticides/analysis
3.
Anal Methods ; 16(10): 1546-1553, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38404205

ABSTRACT

The compound 3-phenoxybenzoic acid (3-PBA) is frequently utilized as a biomarker to detect exposure to various pyrethroids. In this study, a bivalent nanobody (Nb2) specifically targeting 3-PBA was biotinylated and immobilized onto streptavidin (SA)-modified bacterial magnetic nanoparticles (BMPs), resulting in the formation of BMP-SA-Biotin-Nb2 complexes. These complexes demonstrated remarkable stability when exposed to strongly acidic solutions (4 M HCl), methanol (80%), and high ionic strength (1.37 M NaCl). An immunoassay was subsequently developed utilizing BMP-SA-Biotin-Nb2 as the capture agent and 3-PBA-horseradish peroxidase as the detection probe. The immunoassay exhibited an IC50 value (half-maximum signal inhibition concentration) of 1.11 ng mL-1 for 3-PBA. To evaluate the accuracy of the assay, spiked sheep and cow urine samples (ranging from 3.0 to 240 ng mL-1) were analyzed. The quantitative recoveries ranged from 82.5% to 113.1%, which agreed well with the findings obtained using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Overall, the BMP-SA-Biotin-Nb2-based immunoassay holds great promise for rapid monitoring of 3-PBA following acid dissociation.


Subject(s)
Benzoates , Biotin , Magnetosomes , Female , Cattle , Animals , Sheep , Streptavidin/chemistry , Biotin/chemistry , Enzyme-Linked Immunosorbent Assay/methods , Chromatography, Liquid , Tandem Mass Spectrometry
4.
Food Chem ; 441: 138377, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38219367

ABSTRACT

Immunomagnetic beads provide novel tools for high-throughput immunoassay techniques. In this study, protein G (PG) was immobilized onto bacterial magentic particles (BMPs) using an additional cysteine residue at the C-terminus. A broad-spectrum monoclonal antibody against glucocorticoids (GCs) was attached to BMPs through PG-Fc interaction, generating BMP-PG-mIgG immunomagentic beads. A sensitive one-step immunoassay was developed for GCs based on combination of BMP-PG-mIgG and dexamethasone-horseradish peroxidase tracer (DMS-HRP). The developed assay exhibited half inhibitory concentrations (IC50) for dexamethasone (DMS), betamethasone (BMS), prednisolone (PNS), hydrocortisone (HCS), beclomethasone (BCMS), cortisone (CS), 6-α-methylprednisone (6-α-MPNS), fludrocortisone acetate (HFCS) of 0.98, 1.49, 2.42, 9.29, 1.63, 6.13, 7.3, and 4.89 ng/mL, respectively. The method showed recoveries ranging rates from 86.5 % to 117 % with a coefficient of variation less than 12.3 % in milk sample, which showed a good correlation with LC-MS/MS. Thus, the proposed assay offers a rapid and broad-spectrum screening tool for simultaneous detection of GCs in milk.


Subject(s)
Glucocorticoids , Magnetosomes , Animals , Glucocorticoids/analysis , Milk/chemistry , Chromatography, Liquid , Tandem Mass Spectrometry , Immunoassay/methods , Bacteria , Dexamethasone/analysis , Immunomagnetic Separation/methods
5.
Compr Physiol ; 14(1): 5291-5323, 2023 12 29.
Article in English | MEDLINE | ID: mdl-38158368

ABSTRACT

Acquired brain injuries, such as ischemic stroke, intracerebral hemorrhage (ICH), and traumatic brain injury (TBI), can cause severe neurologic damage and even death. Unfortunately, currently, there are no effective and safe treatments to reduce the high disability and mortality rates associated with these brain injuries. However, environmental enrichment (EE) is an emerging approach to treating and rehabilitating acquired brain injuries by promoting motor, sensory, and social stimulation. Multiple preclinical studies have shown that EE benefits functional recovery, including improved motor and cognitive function and psychological benefits mediated by complex protective signaling pathways. This article provides an overview of the enriched environment protocols used in animal models of ischemic stroke, ICH, and TBI, as well as relevant clinical studies, with a particular focus on ischemic stroke. Additionally, we explored studies of animals with stroke and TBI exposed to EE alone or in combination with multiple drugs and other rehabilitation modalities. Finally, we discuss the potential clinical applications of EE in future brain rehabilitation therapy and the molecular and cellular changes caused by EE in rodents with stroke or TBI. This article aims to advance preclinical and clinical research on EE rehabilitation therapy for acquired brain injury. © 2024 American Physiological Society. Compr Physiol 14:5291-5323, 2024.


Subject(s)
Brain Injuries, Traumatic , Brain Injuries , Ischemic Stroke , Stroke , Rats , Animals , Rats, Sprague-Dawley , Environment , Brain Injuries, Traumatic/therapy , Brain Injuries, Traumatic/complications , Brain Injuries/complications , Stroke/therapy , Stroke/complications , Ischemic Stroke/complications , Disease Models, Animal
6.
Sensors (Basel) ; 23(20)2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37896624

ABSTRACT

Selecting training samples is crucial in remote sensing image classification. In this paper, we selected three images-Sentinel-2, GF-1, and Landsat 8-and employed three methods for selecting training samples: grouping selection, entropy-based selection, and direct selection. We then used the selected training samples to train three supervised classification models-random forest (RF), support-vector machine (SVM), and k-nearest neighbor (KNN)-and evaluated the classification results of the three images. According to the experimental results, the three classification models performed similarly. Compared with the entropy-based method, the grouping selection method achieved higher classification accuracy using fewer samples. In addition, the grouping selection method outperformed the direct selection method with the same number of samples. Therefore, the grouping selection method performed the best. When using the grouping selection method, the image classification accuracy increased with the increase in the number of samples within a certain sample size range.

7.
J Cereb Blood Flow Metab ; 43(5): 694-711, 2023 05.
Article in English | MEDLINE | ID: mdl-36635875

ABSTRACT

Post-stroke depression exacerbates neurologic deficits and quality of life. Depression after ischemic stroke is known to some extent. However, depression after intracerebral hemorrhage (ICH) is relatively unknown. Increasing evidence shows that exposure to an enriched environment (EE) after cerebral ischemia/reperfusion injury has neuroprotective effects in animal models, but its impact after ICH is unknown. In this study, we investigated the effect of EE on long-term functional outcomes in mice subjected to collagenase-induced striatal ICH. Mice were subjected to ICH with the standard environment (SE) or ICH with EE for 6 h/day (8:00 am-2:00 pm). Depressive, anxiety-like behaviors and cognitive tests were evaluated on day 28 with the sucrose preference test, tail suspension test, forced swim test, light-dark transition experiment, morris water maze, and novel object recognition test. Exposure to EE improved neurologic function, attenuated depressive and anxiety-like behaviors, and promoted spatial learning and memory. These changes were associated with increased expression of transcription factor Nrf2 and brain-derived neurotrophic factor (BDNF) and inhibited glutaminase activity in the perihematomal tissue. However, EE did not change the above behavioral outcomes in Nrf2-/- mice on day 28. Furthermore, exposure to EE did not increase BDNF expression compared to exposure to SE in Nrf2-/- mice on day 28 after ICH. These findings indicate that EE improves long-term outcomes in sensorimotor, emotional, and cognitive behavior after ICH and that the underlying mechanism involves the Nrf2/BDNF/glutaminase pathway.


Subject(s)
Brain-Derived Neurotrophic Factor , NF-E2-Related Factor 2 , Mice , Animals , Brain-Derived Neurotrophic Factor/metabolism , Glutaminase , Quality of Life , Cerebral Hemorrhage/metabolism , Disease Models, Animal
8.
J Environ Sci Health B ; 57(11): 883-889, 2022.
Article in English | MEDLINE | ID: mdl-36217592

ABSTRACT

The heterologous strategy could improve the sensitivity of competitive enzyme-linked immunosorbent assay (ELISA) for detection of chemical contaminants in food samples. In this study, the heterologous coating antigen ELISA was developed to evaluate its sensitivity for mebendazole (MBZ). Results showed that the heterologous ELISA had a linear range of (IC20-IC80) 0.34-10.54 ng/mL, an IC50 value of 1.83 ng/mL, and a limit of detection (LOD) of 0.13 ng/mL, in which the sensitivity of ELISA improved 1.7- and 2-fold (IC50 value dropping from 7.41 and 3.65 ng/mL to 4.27 and 1.83 ng/mL) than that of rabbit IgG- and chicken IgY-based homologous ELISA for MBZ, respectively. The heterologous coating antigen ELISA showed negligible cross reactivity (<0.2%) with its structural analogues, including hydroxy-MBZ, albendazole, oxfendazole, fenbendazole, and flubendazole, except the value of 72.6% for amino-MBZ. The average recoveries of MBZ spiked in pork and chicken muscle samples by the assay ranged from 83.7% to 109.8% and agreed well with those of high-performance liquid chromatography. The results suggested that using heterologous coating antigen could distinctly improve the sensitivity of ELISA for routine screening of MBZ residues in food samples.


Subject(s)
Antigens, Heterophile , Mebendazole , Animals , Rabbits , Antigens, Heterophile/analysis , Enzyme-Linked Immunosorbent Assay/methods , Chromatography, High Pressure Liquid , Limit of Detection
9.
ACS Omega ; 7(34): 30093-30103, 2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36061653

ABSTRACT

As a most promising formaldehyde-free crosslinking agent for the antiwrinkle treatment of cotton fabrics, 1,2,3,4-butanetetracarboxylic acid (BTCA) has been explored for many years to replace the traditional N-methylol resin. However, the current methodology for preparing antiwrinkle cotton fabrics with BTCA mainly highlights the troublesome problem of higher curing temperature. In this research, a novel strategy with the aid of dimethyl sulfone (MSM) was developed to decrease the curing temperature of BTCA for fabricating antiwrinkle cotton fabrics, which is an eco-friendly additive with low price and wonderful biocompatibility. Temperature-dependent Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and computational simulations were employed to analyze the mechanism of MSM in the overall reaction between BTCA and cellulose. Based on the strong hydrogen-bond acceptor property of MSM, the noncovalent interactions in the crosslinking system could be easily interrupted, which facilitates the BTCA diffusion in amorphous regions of cellulose, anhydride formation, and the thermal vibration of cellulose chains during the processing. Physically and chemically speaking, both reactivities of grafting and crosslinking reactions of BTCA are significantly increased with the assistance of MSM, consequently reducing the curing temperature, which will hopefully help achieve the industrial-scale application of BTCA in antiwrinkle treatment.

10.
Int J Nanomedicine ; 17: 665-680, 2022.
Article in English | MEDLINE | ID: mdl-35185331

ABSTRACT

PURPOSE: Nanoparticles (NPs) decorated with functional ligands are promising candidates for cancer diagnosis and treatment. However, numerous studies have shown that chemically coupled targeting moieties on NPs lose their targeting capability in the biological milieu because they are shielded or covered by a "protein corona". Herein, we construct a functional magnetosome that recognizes and targets cancer cells even in the presence of protein corona. METHODS: Magnetosomes (BMPs) were extracted from magnetotactic bacteria, M. gryphiswaldense (MSR-1), and decorated with trastuzumab (TZ) via affibody (RA) and glutaraldehyde (GA). The engineered BMPs are referred to as BMP-RA-TZ and BMP-GA-TZ. Their capacities to combine HER2 were detected by ELISA, the quantity of plasma corona proteins was analyzed using LC-MS. The efficiencies of targeting SK-BR-3 were demonstrated by confocal laser scanning microscopy and flow cytometry. RESULTS: Both engineered BMPs contain up to ~0.2 mg TZ per mg of BMP, while the quantity of HER2 binding to BMP-RA-TZ is three times higher than that binding to BMP-GA-TZ. After incubation with normal human plasma or IgG-supplemented plasma, GA-TZ-containing BMPs have larger hydrated radii and more surface proteins in comparison with RA-TZ-containing BMPs. The TZ-containing BMPs all can be targeted to and internalized in the HER2-overexpressing breast cancer cell line SK-BR-3; however, their targeting efficiencies vary considerably: 50-75% for RA-TZ-containing BMPs and 9-19% for GA-TZ-containing BMPs. BMPs were incubated with plasma (100%) and cancer cells to simulate human in vivo environment. In this milieu, BMP-RA-TZ uptake efficiency of SK-BR-3 reaches nearly 80% (slightly lower than for direct interaction with BMP-RA-TZ), whereas the BMP-GA-TZ uptake efficiency is <17%. CONCLUSION: Application of the RA scaffold promotes and orients the arrangement of targeting ligands and reduces the shielding effect of corona proteins. This strategy improves the targeting capability and drug delivery of NP in a simulated in vivo milieu.


Subject(s)
Magnetosomes , Pharmaceutical Preparations , Protein Corona , Cell Line, Tumor , Drug Delivery Systems , Humans , Magnetosomes/metabolism , Protein Corona/metabolism , Receptor, ErbB-2/metabolism , Trastuzumab/pharmacology
11.
J Environ Sci Health B ; 57(1): 47-53, 2022.
Article in English | MEDLINE | ID: mdl-34978273

ABSTRACT

Chicken egg yolk IgY has proven to be qualified for analysis of targets in immunoassays. In order to explore the feasibility of chicken IgY-based ELISA for detection of mebendazole (MEB), the chicken IgY against MEB was generated in the laying hens. An enzyme-linked immunosorbent assay (ELISA) based on chicken IgY was developed for detection of MEB with a half-maximum signal inhibition concentration (IC50) of 3.65 ng mL-1 and a limit of detection of 0.25 ng mL-1. The assay showed a lower cross reactivity (less than 1%) with other structures analogues (except amino-MEB with the values of 70.7%). The average recoveries of MEB spiked in pork and mutton muscle samples ranged from 93.6% to 106.3% with relative standard deviation less than 8.78% and 10.85% for intra-assay and inter-assay, respectively, and agreed well with those of high-performance liquid chromatography. Our results indicate that generated IgY could be used as a robust reagent for routine screening analysis of small molecular compounds residues in food samples.


Subject(s)
Pork Meat , Red Meat , Animals , Chickens , Egg Yolk/chemistry , Enzyme-Linked Immunosorbent Assay/methods , Female , Immunoglobulins/analysis , Mebendazole/analysis , Swine
12.
Neurol Res ; 44(1): 65-89, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34308784

ABSTRACT

Traumatic brain injury (TBI) is a medical emergency with high morbidity and mortality. Motor, memory, and emotion-related deficits are common symptoms following TBI, yet treatment is very limited. To develop new drugs and find new therapeutic avenues, a wide variety of TBI models have been established to mimic the heterogeneity of TBI. In this regard, along with histologic measures, behavioral functional outcomes provide valuable insight into the underlying neuropathology and guide neurorehabilitation efforts for neuropsychiatric impairment after TBI. Development, characterization, and application of behavioral tests that can assess functional neurologic deficits are essential to the development of translational therapies. This comprehensive review aims to summarize 19 common behavioral tests from three aspects (motor, memory, and emotion-related) that are associated with TBI pathology. Discussion covers the apparatus, the test steps, the evaluation indexes, data collection and analysis, animal performance and applications, advantages and disadvantages as well as precautions to eliminate bias wherever possible. We discussed recent studies on TBI-related preconditioning, biomarkers, and optimized behavioral protocols. The neuropsychologic tests employed in clinics were correlated with those used in mouse TBI models. In summary, this review provides a comprehensive, up-to-date reference for TBI researchers to choose the right neurobehavioral protocol according to the research objectives of their translational investigation.


Subject(s)
Behavior Rating Scale , Brain Injuries, Traumatic , Animals , Brain Injuries, Traumatic/pathology , Disease Models, Animal , Emotions , Mice
13.
Anal Methods ; 13(43): 5247-5253, 2021 11 11.
Article in English | MEDLINE | ID: mdl-34708839

ABSTRACT

The 3-phenoxybenzoic acid (3-PBA) metabolized from pyrethroids is more toxic and has a longer half-life to degradation in a natural environment compared to its parent compounds. Few reports have focused on the environmental detection of 3-PBA. In this study, anti-3-PBA nanobodies in trivalent form (Nb3) were biotinylated. A sensitive enzyme-linked immunosorbent assay (ELISA) based on the combination of Nb3-biotin and streptavidin-horseradish peroxidase (SA-HRP) was developed for the environmental detection of 3-PBA. After optimization, the ELISA showed a half-maximum signal inhibition concentration (IC50) of 0.39 ng mL-1 in phosphate-buffered saline (pH 7, 20% MeOH) and a limit of detection (LOD) of 0.02 ng mL-1, which was more sensitive than the parent Nb-based ELISAs with IC50 and LOD values of 1.4 ng mL-1 and 0.1 ng mL-1, respectively. The Nb3-biotin amplified assay showed negligible cross-reactivity with its structural analogues (<0.1%). The average recoveries of 3-PBA from spiked canal water and soil samples ranged from 86.54-109.25% at 0.5-50 ng mL-1 (or ng g-1 (dw)). The 3-PBA residues in canal water and soil samples determined using this assay were in the ranges

Subject(s)
Benzoates , Biotin , Biotin/chemistry , Enzyme-Linked Immunosorbent Assay/methods , Streptavidin/chemistry
14.
Anal Biochem ; 632: 114390, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34560055

ABSTRACT

Nanobodies (Nbs) as capture antibodies in enzyme-linked immunosorbent assays (ELISAs) is greatly hampered by their poor performance after attaching onto polystyrene microplates. Reasons behind those phenomena remain unknown. One of possible explanation is that Nbs with a single domain might lose their accessibility of paratope when adsorbed on the plates. Increasing their binding sites might improve performance in capture Nbs-based ELISA. In this study, anti-3-phenoxybenzoic acid (3-PBA) Nbs was assembled to trivalent form (Nb3) in tandem with flexible linkers (G4S)3. Direct competitive ELISA on the basis of Nb3 and 3-PBA-horseradish peroxidase was developed for detection of 3-PBA in livestock urine. The ELISA had a half-maximum (IC50) inhibition concentration of 0.51 ng/mL, with a limit of detection of 0.02 ng/mL, which was more sensitive than that of the parental Nb with a IC50 of 2.39 ng/mL. The average recoveries of 3-PBA spiked in swine, sheep and dairy cow urine samples by the assay ranged from 89.52% to 114.25% and agreed well with those of liquid chromatography mass spectrometry (LC-MS). The above results indicated that multivalent Nbs could be treated as the capture antibody in ELISA for routine screening analysis of 3-PBA residues in urine.


Subject(s)
Antibodies/chemistry , Benzoates/urine , Enzyme-Linked Immunosorbent Assay , Single-Domain Antibodies/chemistry , Animals , Cattle , Sheep , Swine
15.
Front Cell Neurosci ; 15: 699736, 2021.
Article in English | MEDLINE | ID: mdl-34512265

ABSTRACT

Disruption of the blood-brain barrier (BBB) and the subsequent formation of brain edema is the most severe consequence of intracerebral hemorrhage (ICH), leading to drastic neuroinflammatory responses and neuronal cell death. A better understanding of ICH pathophysiology to develop effective therapy relies on selecting appropriate animal models. The collagenase injection ICH model and the autologous arterial whole blood infusion ICH model have been developed to investigate the pathophysiology of ICH. However, it remains unclear whether the temporal progression and the underlying mechanism of BBB breakdown are similar between these two ICH models. In this study, we aimed to determine the progression and the mechanism of BBB disruption via the two commonly used murine ICH models: the collagenase-induced ICH model (c-ICH) and the double autologous whole blood ICH model (b-ICH). Intrastriatal injection of 0.05 U collagenase or 20 µL autologous blood was used for a comparable hematoma volume in these two ICH models. Then we analyzed BBB permeability using Evan's blue and IgG extravasation, evaluated tight junction (TJ) damage by transmission electron microscope (TEM) and Western blotting, and assessed matrix metalloproteinase-9 (MMP-9) activity and aquaporin 4 (AQP4) mRNA expression by Gelatin gel zymography and RT-PCR, respectively. The results showed that the BBB leakage was associated with a decrease in TJ protein expression and an increase in MMP-9 activity and AQP4 expression on day 3 in the c-ICH model compared with that on day 5 in the b-ICH model. Additionally, using TEM, we found that the TJ was markedly damaged on day 3 in the c-ICH model compared with that on day 5 in the b-ICH model. In conclusion, the BBB was disrupted in the two ICH models; compared to the b-ICH model, the c-ICH model presented with a more pronounced disruption of BBB at earlier time points, suggesting that the c-ICH model might be a more suitable model for studying early BBB damage and protection after ICH.

16.
Anal Methods ; 13(14): 1740-1746, 2021 04 14.
Article in English | MEDLINE | ID: mdl-33861241

ABSTRACT

Mebendazole (MBZ), a synthetic benzimidazole, is most widely used for the treatment of intestinal helminthiasis. In the present study, a hapten mimicking the MBZ structure was designed by introducing propanoic acid and coupling to carrier proteins by the active ester method to immunize New Zealand rabbits. A sensitive enzyme-linked immunosorbent assay (ELISA) was developed for the analysis of MBZ in food samples. The rabbit IgG based ELISA had a half-maximum inhibition concentration (IC50) of 7.41 ng mL-1, with a limit of detection of 0.27 ng mL-1. The ELISA showed negligible cross reactivity (<1%) with structural analogs, including hydroxy-MBZ, albendazole, oxfendazole, fenbendazole, flubendazole and oxfendazole, except the value of 90.5% for amino-MBZ. The average recoveries of MBZ spiked in chicken and mutton muscle samples by the assay ranged from 84.31% to 106.28% and agreed well with those of high-performance liquid chromatography. The above results indicated that the generated anti-MBZ IgG-based ELISA showed promise in routine screening analysis of MBZ residues in food samples.


Subject(s)
Chickens , Mebendazole , Albendazole , Animals , Enzyme-Linked Immunosorbent Assay , Fenbendazole , Rabbits
17.
J Nanobiotechnology ; 19(1): 27, 2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33468141

ABSTRACT

BACKGROUND: Magnetic nanoparticles such as magnetosomes modified with antibodies allow a high probability of their interaction with targets of interest. Magnetosomes biomineralized by magnetotactic bacteria are in homogeneous nanoscale size and have crystallographic structure, and high thermal and colloidal stability. Camelidae derived nanobodies (Nbs) are small in size, thermal stable, highly water soluble, easy to produce, and fusible with magnetosomes. We aimed to functionalize Nb-magnetosomes for the analysis of the insecticide fipronil. RESULTS: Three recombinant magnetotactic bacteria (CF, CF+ , and CFFF) biomineralizing magnetosomes with different abundance of Nbs displayed on the surface were constructed. Compared to magnetosomes from the wild type Magnetospirillum gryphiswaldense MSR-1, all of the Nb-magnetosomes biosynthesized by strains CF, CF+ , and CFFF showed a detectable level of binding capability to fipronil-horseradish peroxidase (H2-HRP), but none of them recognized free fipronil. The Nb-magnetosomes from CFFF were oxidized with H2O2 or a glutathione mixture consisting of reduced glutathione and oxidized glutathione in vitro and their binding affinity to H2-HRP was decreased, whereas that to free fipronil was enhanced. The magnetosomes treated with the glutathione mixture were employed to develop an enzyme-linked immunosorbent assay for the detection of fipronil in water samples, with average recoveries in a range of 78-101%. CONCLUSIONS: The economical and environmental-friendly Nb-magnetosomes biomineralized by the bacterial strain MSR-1 can be potentially applied to nanobody-based immunoassays for the detection of fipronil or nanobody-based assays in general.


Subject(s)
Insecticides/chemistry , Magnetosomes , Magnetospirillum/metabolism , Pyrazoles/chemistry , Single-Domain Antibodies/chemistry , Single-Domain Antibodies/metabolism , Bacillus subtilis/genetics , Bacterial Proteins/metabolism , Batch Cell Culture Techniques , Fermentation , Glutathione , Hydrogen Peroxide/metabolism , Immunoassay , Magnetospirillum/genetics , Single-Chain Antibodies
18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 1025-1030, 2020 Dec 25.
Article in Chinese | MEDLINE | ID: mdl-33369341

ABSTRACT

During the COVID-19 epidemic, our national guidelines have suggested that surgical patients should wear a mask to decrease the potential transmission of COVID-19 in the operating room, as long as the condition allows. However, so far, there is no study to discuss the influence of wearing a mask on the ventilation and blood oxygenation status in patients of spontaneous breathing with supplementary oxygen through an anesthetic facemask. This is a before-after study in the same patient, and 10 healthy volunteers were recruited, by testing the arterial blood gas parameters at key time points before and after oxygen inhalation to evaluate the effects of two different supplementary oxygen methods ('disposable medical mask + anesthetic facemask' and 'anesthetic facemask only') on the oxygenation of subjects. Our data demonstrated whether wearing a disposable medical mask or not could effectively increase the oxygen supply of the subjects compared with the basic value before oxygen inhalation; however, compared with the group without mask, the arterial oxygen partial (PaO 2) reduced significantly at each time points when subjects wearing a disposable medical mask. There was no significant difference in other parameters, and our data showed that age growth and smoking had no significant effects on the difference of PaO 2 between the groups with and without masks. This study demonstrates effective oxygen supplementation through anesthetic facemask in subjects with spontaneous breathing who is wearing a disposable medical mask, whose pulse oxygen saturation and arterial oxygen saturation can reach 100% rapidly, and this provides a theoretical basis for the management of patients with disseminated respiratory diseases to wear masks in the operating room; however, the rate and amount of PaO 2 increase are both decreased as compared to those who is not wearing a disposable medical mask during supplementary oxygenation. Whether this difference will affect the clinical outcome needs further study.


Subject(s)
Masks , Oxygen/administration & dosage , Oxygen/blood , COVID-19 , Healthy Volunteers , Humans , Oximetry
19.
Heliyon ; 6(9): e04911, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32984608

ABSTRACT

Recently, natural dyes have a widening scope in various traditional and advanced applications due to their eco-friendly environment. However, improved dyeability of natural dyes still remains a challenging task. This research was aimed to achieve multi-objective wool with improved dyeability using bio-nano-mordant composed of m-Trans-glutaminase, m-TGase, and bentonite nanoclay. Wool fiber was treated through sonochemical method using different concentrations of m-TGase and bentonite. The surface morphology of wool fabric samples was examined by field emission-scanning electron microscopy (FESEM), and Fourier transform Infrared Radiation (FTIR). Further, wool samples treated at different conditions were applied to madder for dyeability examination. The optimum conditions of color coordinates, color strength, K/S, and washing fastness of madder on treated wool fabric with m-TGase and bentonite, were also examined. The results revealed well-made interactions among m-TGase, bentonite, and wool fibers. In addition, surface morphology was strongly influenced by variations in enzyme concentrations so that extra addition of m-TGase lead to clear damage scales or less cuticle surface in SEM images. Moreover, the results showed that the value of K/S for treated wool samples was better than untreated samples. Indeed, amongst all, 5% concentrations of bio-nano-mordant for m-TGase and bentonite have the most constructive K/S values. Similarly, results of ΔE and antibacterial investigations also confirmed its superiority.

20.
Anal Chem ; 92(1): 1114-1121, 2020 01 07.
Article in English | MEDLINE | ID: mdl-31763820

ABSTRACT

Bacterial magnetic particles (BMPs) are an attractive carrier material for immunoassays because of their nanoscale size, dispersal ability, and membrane-bound structure. Antitetrabromobisphenol-A (TBBPA) nanobodies (Nbs) in the form of monovalence (Nb1), bivalence (Nb2), and trivalence (Nb3) were biotinylated and immobilized onto streptavidin (SA)-derivatized BMPs to construct the complexes of BMP-SA-Biotin-Nb1, -Nb2, and -Nb3, respectively. An increasing order of binding capability of BMP-SA-Biotin-Nb1, -Nb2, and -Nb3 to TBBPA was observed. These complexes showed high resilience to temperature (90 °C), methanol (100%), high pH (12), and strong ionic strength (1.37 M NaCl). A BMP-SA-Biotin-Nb3-based enzyme linked immunosorbent assay (ELISA) for TBBPA dissolved in methanol was developed, showing a half-maximum inhibition concentration (IC50) of 0.42 ng mL-1. TBBPA residues in landfill leachate, sewage, and sludge samples determined by this assay were in a range of

Subject(s)
Antibodies, Immobilized/immunology , Enzyme-Linked Immunosorbent Assay/methods , Magnetosomes/chemistry , Polybrominated Biphenyls/analysis , Single-Domain Antibodies/immunology , Water Pollutants, Chemical/analysis , Amino Acid Sequence , Ferrosoferric Oxide/chemistry , Flame Retardants/analysis , Iron/chemistry , Limit of Detection , Magnetospirillum/chemistry , Polybrominated Biphenyls/immunology , Sewage/analysis , Sulfides/chemistry , Water Pollutants, Chemical/immunology
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