In Situ Sample Cleanup during Immunoassay: A Simple Method for Rapid Detection of Aflatoxin B1 in Food Samples

A strategy for rapid in situ elimination of interfering substances that are present in extracts of food samples during assay is described in this article. The novel feature of this method is that the sample purification is carried out as a part of the assay, and a separate sample cleanup step is not required. The assay procedure involves the sequential addition of standard or sample, cleaning solutions, and aflatoxin B1–horseradish peroxidase conjugate (AFB1-HRP) over antibody-spotted zones of a membrane, and 3,3′-diaminobenzidine was used as the substrate for visualization. We have determined that trifluoroacetic acid and propionic acids at concentrations of 100 mM are highly effective for cleaning groundnut, wheat, corn, and poultry feed samples and that NaHCO3 (100 mM) is successful in cleaning processed soybean. In all cases, subsequent washing was performed with phosphate-buffered saline solution to facilitate the removal of traces of adhering interfering substances. A batch of 12 samples can be analyzed within 8 min either by visual comparison of the color intensity (inversely related to the analyte concentration) of a sample spot with those of reference standards or, more precisely, by densitometry. The method was tested for the analysis of AFB1 in groundnut, wheat, corn, processed soybean, chili, and poultry feed. The detection limit obtained was 5 μg/kg, except for chili, where it was 10 μg/kg. The average recoveries from different noninfected food samples spiked with AFB1 at concentrations of 5 to 100 μg/kg were between 99 and 105%. The values obtained for infected corn and groundnut samples correlated well with the estimates obtained by high-pressure liquid chromatography. The absence of a sample extraction step reduces the cost and labor involved in the assay. The method may be potentially applicable to the assay of other mycotoxins and environmental pollutants.

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Biodegradation of polycyclic aromatic hydrocarbons (PAH) in marine sediment under denitrifying conditions

Water Science & Technology ◽

10.2166/wst.1998.0463 ◽

1998 ◽

Vol 38 (11) ◽

pp. 177-185 ◽

Cited By ~ 12

Author(s):

Jean D. MacRae ◽

Kenneth J. Hall

Keyword(s):

Molecular Weight ◽

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Marine Sediment ◽

Environmental Pollutants ◽

Ex Situ ◽

Polycyclic Aromatic ◽

Bottom Fish ◽

The Cost

Polycyclic Aromatic Hydrocarbons (PAH) are common environmental pollutants that have been linked to cancerous lesions in bottom fish. In this research, the feasibility of using nitrate as an alternative electron acceptor to stimulate PAH-degradation in anoxic marine sediment was investigated. PAH could be degraded under denitrifying conditions as long as other nutrients were not limiting. The half lives of low molecular weight PAH ranged from approximately 33-88 days. Degradation of high molecular weight PAH was slower, or not observed. Half lives ranged from 143-812 days. Nitrate may be applied to sediments in situ or used in bioreactors to reduce the cost of bioremediation operations ex situ.

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Creation of Statistically Equivalent Periodic Unit Cells for Protein-Bound Soils

Volume 9: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2015-52029 ◽

2015 ◽

Cited By ~ 1

Author(s):

Isamar Rosa ◽

Henning Roedel ◽

Michael D. Lepech ◽

David J. Loftus

Keyword(s):

Space Station ◽

Construction Materials ◽

Experimental Tests ◽

Ct Scanning ◽

Long Duration ◽

Unit Cells ◽

Model Protein ◽

Sequential Addition ◽

The Cost

In 2010, NASA was directed to develop technologies to reduce the cost and risk of space exploration and send humans beyond the International Space Station. A central challenge to long-duration space missions is a lack of available construction materials in situ. This work focuses on a novel class of composites that can be produced extraterrestrially in situ by desiccating a mixture of soil, water, and protein binder to create a strong, versatile material. To date, experimental tests of mechanical properties have shown significant variability among samples. This paper focuses on the creation of Statistically Equivalent Periodic Unit Cells (SEPUC) to stochastically model protein-bound composites for the purpose of creating FE models that provide insights into experimental results. Model inputs include the soil granulometry and volume fractions of the phases. Ellipsoidal particles are placed, and protein coatings and bridges are created, using a Level Set based Random Sequential Addition algorithm. Each image is assigned a statistical descriptor and a simple genetic algorithm is used to optimize for a statistical descriptor close to that of experimental specimens. The framework is validated by comparing experimental images of protein-bound soils obtained by micro-CT scanning with those obtained through the SEPUC framework.

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Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099192 ◽

1981 ◽

Vol 39 ◽

pp. 550-551

Author(s):

Dean A. Handley ◽

Jack T. Alexander ◽

Shu Chien

Keyword(s):

Cell Growth ◽

Cell Cultures ◽

Molecular Interactions ◽

Convenient Method ◽

Petri Dish ◽

Simple Method ◽

Thin Section Microscopy ◽

Thin Sectioning ◽

Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

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A Mild and Simple Method for Making MIDA Boronates

10.26434/chemrxiv.12054036.v1 ◽

2020 ◽

Author(s):

Aidan Kelly ◽

Peng-Jui (Ruby) Chen ◽

Jenna Klubnick ◽

Daniel J. Blair ◽

Martin D. Burke

Keyword(s):

Organic Synthesis ◽

Boronic Acids ◽

Simple Method ◽

Direct Preparation ◽

Synthesis Procedure ◽

Harsh Conditions

<div> <div> <div> <p>Existing methods for making MIDA boronates require harsh conditions and complex procedures to achieve dehydration. Here we disclose that a pre-dried form of MIDA, MIDA anhydride, acts as both a source of the MIDA ligand and an in situ desiccant to enable a mild and simple MIDA boronate synthesis procedure. This method expands the range of sensitive boronic acids that can be converted into their MIDA boronate counterparts. Further utilizing unique properties of MIDA boronates, we have developed a MIDA Boronate Maker Kit which enables the direct preparation and purification of MIDA boronates from boronic acids using only heating and centrifuge equipment that is widely available in labs that do not specialize in organic synthesis. </p> </div> </div> </div>

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Seawater Absorption and Adhesion Properties of Hydrophobic and Superhydrophobic Thermoset Epoxy Nanocomposite Coatings

Nanomaterials ◽

10.3390/nano11020272 ◽

2021 ◽

Vol 11 (2) ◽

pp. 272

Author(s):

Ayman M. Atta ◽

Mohamed H. El-Newehy ◽

Meera Moydeen Abdulhameed ◽

Mohamed H. Wahby ◽

Ahmed I. Hashem

Keyword(s):

Thermal Stability ◽

Oleic Acid ◽

Salt Spray ◽

Adhesion Properties ◽

In Situ Modification ◽

Long Time ◽

Seawater Environment ◽

Thermoset Epoxy ◽

The Cost

The enhancement of both thermal and mechanical properties of epoxy materials using nanomaterials becomes a target in coating of the steel to protect it from aggressive environmental conditions for a long time, with reducing the cost. In this respect, the adhesion properties of the epoxy with the steel surfaces, and its proper superhyrophobicity to repel the seawater humidity, can be optimized via addition of green nanoparticles (NPs). In-situ modification of silver (Ag) and calcium carbonate (CaCO3) NPs with oleic acid (OA) was carried out during the formation of Ag−OA and CaCO3−OA, respectively. The epoxide oleic acid (EOA) was also used as capping for Ca−O3 NPs by in-situ method and epoxidation of Ag−OA NPs, too. The morphology, thermal stability, and the diameters of NPs, as well as their dispersion in organic solvent, were investigated. The effects of the prepared NPs on the exothermic curing of the epoxy resins in the presence of polyamines, flexibility or rigidity of epoxy coatings, wettability, and coatings durability in aggressive seawater environment were studied. The obtained results confirmed that the proper superhyrophobicity, coating adhesion, and thermal stability of the epoxy were improved after exposure to salt spray fog for 2000 h at 36 °C.

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Alcohol oxidase-driven in situ synthesis of BSA-stabilized copper nanoclusters for precise monitoring of methyl mercaptan in food samples

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2021.130311 ◽

2021 ◽

pp. 130311

Author(s):

Jiayu Jian ◽

Xiao Xiao ◽

Jinxuan Cao ◽

Yizhong Shen

Keyword(s):

Alcohol Oxidase ◽

Food Samples ◽

In Situ Synthesis ◽

Methyl Mercaptan ◽

Copper Nanoclusters

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Assessing an Atmospheric Correction Algorithm for Time Series of Satellite-Based Water-Leaving Reflectance Using Match-Up Sites in Australian Coastal Waters

Remote Sensing ◽

10.3390/rs13101927 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1927

Author(s):

Fuqin Li ◽

David Jupp ◽

Thomas Schroeder ◽

Stephen Sagar ◽

Joshua Sixsmith ◽

...

Keyword(s):

Coastal Waters ◽

Atmospheric Correction ◽

Correction Method ◽

In Situ Measurements ◽

Landsat 8 ◽

Correction Algorithm ◽

Simple Method ◽

North East ◽

The Impact

An atmospheric correction algorithm for medium-resolution satellite data over general water surfaces (open/coastal, estuarine and inland waters) has been assessed in Australian coastal waters. In situ measurements at four match-up sites were used with 21 Landsat 8 images acquired between 2014 and 2017. Three aerosol sources (AERONET, MODIS ocean aerosol and climatology) were used to test the impact of the selection of aerosol optical depth (AOD) and Ångström coefficient on the retrieved accuracy. The initial results showed that the satellite-derived water-leaving reflectance can have good agreement with the in situ measurements, provided that the sun glint is handled effectively. Although the AERONET aerosol data performed best, the contemporary satellite-derived aerosol information from MODIS or an aerosol climatology could also be as effective, and should be assessed with further in situ measurements. Two sun glint correction strategies were assessed for their ability to remove the glint bias. The most successful one used the average of two shortwave infrared (SWIR) bands to represent sun glint and subtracted it from each band. Using this sun glint correction method, the mean all-band error of the retrieved water-leaving reflectance at the Lucinda Jetty Coastal Observatory (LJCO) in north east Australia was close to 4% and unbiased over 14 acquisitions. A persistent bias in the other strategy was likely due to the sky radiance being non-uniform for the selected images. In regard to future options for an operational sun glint correction, the simple method may be sufficient for clear skies until a physically based method has been established.

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Black Soldier Fly Larval Valorization Benefitting from Ex-Situ Fungal Fermentation in Reducing Coconut Endosperm Waste

Processes ◽

10.3390/pr9020275 ◽

2021 ◽

Vol 9 (2) ◽

pp. 275

Author(s):

Chung Yiin Wong ◽

Kunlanan Kiatkittipong ◽

Worapon Kiatkittipong ◽

Seteno K. O. Ntwampe ◽

Man Kee Lam ◽

...

Keyword(s):

Principal Component ◽

Correlation Study ◽

Statistical Correlation ◽

Waste Reduction ◽

Ex Situ ◽

Larval Feeding ◽

Rhizopus Oligosporus ◽

Black Soldier Fly ◽

The Cost

Oftentimes, the employment of entomoremediation to reduce organic wastes encounters ubiquitous shortcomings, i.e., ineffectiveness to valorize recalcitrant organics in wastes. Considering the cost-favorability, a fermentation process can be employed to facilitate the degradation of biopolymers into smaller organics, easing the subsequent entomoremediation process. However, the efficacy of in situ fermentation was found impeded by the black soldier fly larvae (BSFL) in the current study to reduce coconut endosperm waste (CEW). Indeed, by changing into ex situ fermentation, in which the fungal Rhizopus oligosporus was permitted to execute fermentation on CEW prior to the larval feeding, the reduction of CEW was significantly enhanced. In this regard, the waste reduction index of CEW by BSFL was almost doubled as opposed to in situ fermentation, even with the inoculation of merely 0.5 wt % of Rhizopus oligosporus. Moreover, with only 0.02 wt % of fungal inoculation size to execute the ex situ fermentation on CEW, it could spur BSFL growth by about 50%. Finally, from the statistical correlation study using principal component analysis, the presence of Rhizopus oligosporus in a range of 0.5–1.0 wt % was regarded as optimum to ferment CEW via ex situ mode, prior to the valorization by BSFL in reducing the CEW.

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