High-Throughput Screening Methods in Toxicity Testing

AbstractInvasive plants offer an interesting and unconventional source of protein and the considerable investment made towards their eradication can potentially be salvaged through their revalorisation. To identify viable sources, effective and high-throughput screening methods are required, as well as efficient procedures to isolate these components. Rigorous assessment of low-cost, high-throughput screening assays for total sugar, phenolics and protein was performed, and ninhydrin, Lever and Fast Blue assays were found to be most suitable owing to high reliability scores and false positive errors less than 1%. These assays were used to characterise invasive Scottish plants such as Gorse (Ulex europeans), Broom (Cystisus scoparius) and Fireweed (Chamaenerion angustifolium). Protein extraction (alkali-, heat- and enzyme assisted) were tested on these plants, and further purification (acid and ethanol precipitation, as well as ultrafiltration) procedures were tested on Gorse, based on protein recovery values. Cellulase treatment and ethanol precipitation gave the highest protein recovery (64.0 ± 0.5%) and purity (96.8 ± 0.1%) with Gorse. The amino acid profile of the purified protein revealed high levels of essential amino acids (34.8 ± 0.0%). Comparison of results with preceding literature revealed a strong association between amino acid profiles and overall protein recovery with the extraction method employed. The final purity of the protein concentrates was closely associated to the protein content of the initial plant mass. Leaf protein extraction technology can effectively raise crop harvest indices, revalorise underutilised plants and waste streams.

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Evaluation of Methods To Assess the Biofilm-Forming Ability of Listeria monocytogenes

Journal of Food Protection ◽

10.4315/0362-028x.jfp-11-464 ◽

2012 ◽

Vol 75 (8) ◽

pp. 1411-1417 ◽

Cited By ~ 25

Author(s):

ANTÓNIO LOURENÇO ◽

FRANCISCO REGO ◽

LUISA BRITO ◽

JOSEPH F. FRANK

Keyword(s):

Stainless Steel ◽

Listeria Monocytogenes ◽

High Throughput ◽

Biofilm Formation ◽

High Throughput Screening ◽

Screening Methods ◽

Genetic Lineage ◽

Production Lines ◽

Genetic Characteristics

The contamination of ready-to-eat products with Listeria monocytogenes has been related to the presence of biofilms in production lines, as biofilms protect cells from chemical sanitizers. The ability of L. monocytogenes to produce biofilms is often evaluated using in vitro methodologies. This work aims to compare the most frequently used methodologies, including high-throughput screening methods based on microplates (crystal violet and the Calgary Biofilm Device) and methods based on CFU enumeration and microscopy after growth on stainless steel. Thirty isolates with diverse origins and genetic characteristics were evaluated. No (or low) correlations between methods were observed. The only significant correlation was found between the methods using stainless steel. No statistically significant correlation (P > 0.05) was detected among genetic lineage, serovar, and biofilm-forming ability. Because results indicate that biofilm formation is influenced by the surface material, the extrapolation of results from high-throughput methods using microplates to more industrially relevant surfaces should be undertaken with caution.

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High-throughput Screening Methods Developed for Oxidoreductases

Enzyme Assays ◽

10.1002/3527607846.ch3 ◽

2006 ◽

pp. 77-93 ◽

Cited By ~ 6

Author(s):

Tyler W. Johannes ◽

Ryan D. Woodyer ◽

Huimin Zhao

Keyword(s):

High Throughput ◽

High Throughput Screening ◽

Screening Methods

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Paper-Based SERS Platform for One-Step Screening of Tetracycline in Milk

Scientific Reports ◽

10.1038/s41598-019-54380-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Ana Marques ◽

Bruno Veigas ◽

Andreia Araújo ◽

Beatriz Pagará ◽

Pedro Viana Baptista ◽

...

Keyword(s):

High Throughput ◽

High Throughput Screening ◽

Point Of Care ◽

Dairy Industry ◽

Principal Component ◽

Surface Enhanced Raman Spectroscopy ◽

Economic Losses ◽

Screening Methods ◽

Sers Substrate ◽

Molecular Signatures

AbstractThroughout the last decade, the expansion of food testing has been gradually moving towards ordinary high throughput screening methods performed on-site. The demand for point-of-care testing, able to distinguish molecular signatures with high accuracy, sensitivity and specificity has been significantly increasing. This new requirement relies on the on-site detection and monitorization of molecular signatures suitable for the surveillance of food production and processing. The widespread use of antibiotics has contributed to disease control of livestock but has also created problems for the dairy industry and consumers. Its therapeutic and subtherapeutic use has increased the risk of contamination in milk in enough concentrations to cause economic losses to the dairy industry and have a health impact in highly sensitive individuals. This study focuses on the development of a simple Surface-Enhanced Raman Spectroscopy (SERS) method for fast high throughput screening of tetracycline (TET) in milk. For this, we integrate a paper-based low-cost, fully recyclable and highly stable SERS platform, with a minimal sample preparation protocol. A two-microliter sample of milk solutions spiked with TET (from 0.01 to 1000 ppm) is dried on a silver nanoparticle coated cardboard substrate and measured via a Raman spectrophotometer. The SERS substrate showed to be extremely stable with a shelf life of several months. A global spectrum principal component analysis approach was used to test all the detected vibrational modes and their correlation with TET concentration. Peak intensity ratios (455 cm−1/1280 cm−1 and 874 cm−1/1397 cm−1) were found to be correlated with TET concentrations in milk, achieving a sensitivity as low as 0.1 ppm. Results indicate that this SERS method combined with portable Raman spectrometer is a potential tool that can be used on-site for the monitoring of TET residues and other antibiotics.

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Abstract B10: Development of high-throughput screening methods for detecting germline cancer causing mutations in the Hispanic population

10.1158/1538-7755.disp13-b10 ◽

2014 ◽

Author(s):

Ruta Sahasrabudhe ◽

Anna-Marie Tuazon ◽

Paul Lott ◽

Ana Estrada ◽

Mabel Bohorquez ◽

...

Keyword(s):

High Throughput ◽

High Throughput Screening ◽

Screening Methods ◽

Hispanic Population

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Meeting Report: High-Throughput Technologies for In Vivo Imaging Agents

Molecular Imaging ◽

10.1162/15353500200505115 ◽

2005 ◽

Vol 4 (2) ◽

pp. 153535002005051 ◽

Cited By ~ 3

Author(s):

Robert J. Gillies ◽

John M. Hoffman ◽

Kit S. Lam ◽

Anne E. Menkens ◽

David R. Piwnica-Worms ◽

...

Keyword(s):

High Throughput ◽

In Vivo Imaging ◽

High Throughput Screening ◽

Imaging Agents ◽

Meeting Report ◽

Screening Methods ◽

Pharmacological Properties ◽

Drug Candidates ◽

Good Imaging

Combinatorial chemistry and high-throughput screening have become standard tools for discovering new drug candidates with suitable pharmacological properties. Now, those same technologies are starting to be applied to the problem of discovering novel in vivo imaging agents. Important differences in the biological and pharmacological properties needed for imaging agents, compared to those for a therapeutic agent, require new screening methods that emphasize those characteristics, such as optimized residence time and tissue specificity, that make for a good imaging agent candidate.

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Novel Cell-Based Hepatitis C Virus Infection Assay for Quantitative High-Throughput Screening of Anti-Hepatitis C Virus Compounds

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02094-13 ◽

2013 ◽

Vol 58 (2) ◽

pp. 995-1004 ◽

Cited By ~ 24

Author(s):

Zongyi Hu ◽

Keng-Hsin Lan ◽

Shanshan He ◽

Manju Swaroop ◽

Xin Hu ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

High Throughput ◽

High Throughput Screening ◽

Dose Range ◽

Hcv Infection ◽

Replication Cycle ◽

Screening Methods ◽

Functional Features ◽

Pharmacologically Active

ABSTRACTTherapy for hepatitis C virus (HCV) infection has advanced with the recent approval of direct-acting antivirals in combination with peginterferon and ribavirin. New antivirals with novel targets are still needed to further improve the treatment of hepatitis C. Previously reported screening methods for HCV inhibitors either are limited to a virus-specific function or apply a screening method at a single dose, which usually leads to high false-positive or -negative rates. We developed a quantitative high-throughput screening (qHTS) assay platform with a cell-based HCV infection system. This highly sensitive assay can be miniaturized to a 1,536-well format for screening of large chemical libraries. All candidates are screened over a 7-concentration dose range to give EC50s (compound concentrations at 50% efficacy) and dose-response curves. Using this assay format, we screened a library of pharmacologically active compounds (LOPAC). Based on the profile of dose-dependent curves of HCV inhibition and cytotoxicity, 22 compounds with adequate curves and EC50s of <10 μM were selected for validation. In two additional independent assays, 17 of them demonstrated specific inhibition of HCV infection. Ten potential candidates with efficacies of >70% and CC50s (compound concentrations at 50% cytotoxicity) of <30 μM from these validated hits were characterized for their target stages in the HCV replication cycle. In this screen, we identified both known and novel hits with diverse structural and functional features targeting various stages of the HCV replication cycle. The pilot screen demonstrates that this assay system is highly robust and effective in identifying novel HCV inhibitors and that it can be readily applied to large-scale screening of small-molecule libraries.

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