Posts classified under: Aside

Development, optimization and implementation of a centralized metabolic soft spot assay

April 2017

Anthony A Paiva, Cheryl Klakouski, Shu Li, Benjamin M Johnson, Yue-Zhong Shu, Jonathan Josephs, Tatyana Zvyaga, Ismael Zamora, Wilson Z Shou

Abstract

Keywords

Dual-concentration incubation; metabolic soft spot; metabolic stability; orthogonal sample pooling; software assisted data processing.

Automatic Identification of Lansoprazole Degradants under Stress Conditions by LC-HRMS with MassChemSite and WebChembase

June 2021.

Stefano Bonciarelli, Jenny Desantis*, Laura Goracci, Lydia Siragusa, Ismael Zamora, Elisabeth Ortega-Carrasco*

Abstract

Stress testing is one of the most important parts of the drug development process, helping to foresee stability problems and to identify degradation products. One of the processes involving stress testing is represented by forced degradation studies, which can predict the impact of certain conditions of pH, moisture, heat, or other negative effects due to transportation or packaging issues on drug potency and purity, ensuring patient safety. Regulatory agencies have been working on a standardization of laboratory procedures since the past two decades. One of the results of those years of intensive research is the International Conference on Harmonization (ICH) guidelines, which clearly define which forced degradation studies should be performed on new drugs, which become a routine work in pharmaceutical laboratories. Since used techniques based on high-performance liquid chromatography coupled with high-resolution mass spectrometry have been developed years ago and are now mastered by pharmaceutical scientists, automation of data analysis, and thus data processing, is becoming a hot topic nowadays. In this work, we present MassChemSite and WebChembase as a tandem to automatize the routine analysis studies without missing information quality, using as a case study the degradation of lansoprazole under acidic, oxidative, basic, and neutral stress conditions.

Dissipation kinetic studies of fenamidone and propamocarb in vegetables under greenhouse conditions using liquid and gas chromatography coupled to high-resolution mass spectrometry

July 2019.

López-Ruiz R; Romero-González R; Serra B; Garrido Frenich A

Abstract

In this study, fenamidone, propamocarb and their transformation products were monitored in cherry tomato, cucumber, and courgette samples. A mixture of both compounds, which have different physico-chemical characteristics, are commercially available (Consento®). For analysis, ultra high-performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) and gas chromatography coupled to Q-Orbitrap mass spectrometry (GC-Q-Orbitrap-MS) were used. The dissipation of these active ingredients was monitored at two doses (normal and double dose) from 1 to 40 days after the application of the commercial product. Half-lives (DT50) were lower than 30 days for both compounds, which indicates low persistence. Metabolites of both compounds were also monitored due to in some cases these can be more dangerous for human health than the parent compounds.

The metabolites monitored were RPA 410193 ((5S)-3-anilino-5-methyl-5-phenylimidazolidine-2,4-dione), acetophenone, 2-phenylpropionic acid, 5-methyl-5-phenylhydantoin and 5-methylhydantoin for fenamidone, and propamocarb hydrochloride (propyl 3-(dimethylamino) propylcarbamate hydrochloride), N-oxide propamocarb (propyl [3-(dimethylnitroryl)propyl]carbamate), oxazoline-2-one propamocarb (3-[3-(dimethylamino)propyl]-4-hydroxy-4-methyl-1,3-oxazolidin-2-one), 2-hydroxypropamocarb and n-desmethyl propamocarb (propyl [3-(methylamino)propyl]carbamate) for propamocarb. In addition, they were detected one day after the application of commercial product, being RPA 410193, the metabolite detected at the highest concentration in samples. Retrospective analysis of incurred samples allowed putative identification of four possible new metabolites of propamocarb and one of fenamidone.

Dissipation studies of famoxadone in vegetables under greenhouse conditions using liquid chromatography coupled to high-resolution mass spectrometry: putative elucidation of a new metabolite

September 2019

López-Ruiz R; Romero-González R; Ortega-Carrasco E; Garrido Frenich A

Abstract

Background

Famoxadone is a pesticide that is used to control fungal diseases and its dissipation in vegetables should be monitored. For that purpose, liquid chromatography coupled to mass spectrometry has been used. 

Results

The dissipation of famoxadone has been monitored in cucumber, cherry tomato and courgette under greenhouse conditions at different doses (single and double), using ultra high-performance liquid chromatography coupled to Orbitrap mass spectrometry (Thermo Fisher Scientific, Bremen, Germany). The concentration of famoxadone increased slightly just after the application of the commercial product and then decreased. The half-lives (DT50 ) of famoxadone are different for each matrix, ranging from 2 days (courgette single dose) to 10 days (cucumber double dose). The main metabolites, 4-phenoxybenzoic acid and 1-acetyl-2-phenylhydrazine, were not detected in vegetable samples. Other metabolites described by the European Food and Safety Authority, such as IN-JS940 [(2RS)-2-hydroxy-2-(4-phenoxyphenyl)propanoic acid], IN-KF015 [(5RS)-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione] and IN-MN467 [(5RS)-5-methyl-3-[(2-nitrophenyl)amino]-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione], were detected in the three matrices. Untargeted analysis allowed for the putative elucidation of a new metabolite of famoxadone in cucumber (up to 290 μg kg-1 ) and cherry tomato (up to 900 μg kg-1 ) samples.  

Conclusion

The dissipation of famoxadone has been investigated in three vegetables: tomato, cucumber, and courgette. The persistence of famoxadone was low in the three matrices (DT50 less than 10 days). Metabolites of famoxadone were monitored, detecting IN-JS940, IN-MN467 and IN-KF015, and the putative elucidation of a new metabolite of famoxadone was performed by applying software tools. 

Automatic MS Data Analysis to reveal the metabolic pathways of pesticides in fruits and soils

256th ACS National Meeting, Boston, MA (United States of America) 21 August, 2018 

Abstract

In the intensive farming of fruit and vegetable, a variety of pesticides are applied to prevent or eliminate harmful pests from plants. These pesticides can remain in edible parts as residues entering into the food chain. In most of the cases, pesticides can be transformed into metabolites, which are intermediate products of metabolism formed either in plants or animals. The detection of those metabolites does not end in the edible parts of the fruits and vegetables. It is also needed a deep study of soils and water to ensure that the concentration of harmful compounds will not reach the limit stablished by law. Advances in analytical techniques with increased sensitivity have led to the detection of a growing number of metabolites at low concentrations, being HPLC-HRMS the most used analytical method to perform this task. To boost the structure elucidation of the different metabolites, we used MassChemSite 2.0.