Fungal Biomarkers Stability in Mars Regolith Analogues after Simulated Space and Mars-like Conditions

The discovery of life on other planets and moons in our solar system is one of the most important challenges of this era. The second ExoMars mission will look for traces of extant or extinct life on Mars. The instruments on board the rover will be able to reach samples with eventual biomarkers until 2 m of depth under the planet’s surface. This exploration capacity offers the best chance to detect biomarkers which would be mainly preserved compared to samples on the surface which are directly exposed to harmful environmental conditions. Starting with the studies of the endolithic meristematic black fungus Cryomyces antarcticus, which has proved its high resistance under extreme conditions, we analyzed the stability and the resistance of fungal biomarkers after exposure to simulated space and Mars-like conditions, with Raman and Gas Chromatography–Mass Spectrometry, two of the scientific payload instruments on board the rover.

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Development and validation of the method for the detection of glimepiride via derivatization employing N-methyl-N-(trimethylsilyl) trifluoroacetamide using gas chromatography-mass spectrometry

Egyptian Journal of Forensic Sciences ◽

10.1186/s41935-021-00217-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Priyanka Verma ◽

Atul Bajaj ◽

R. M. Tripathi ◽

Sudhir K. Shukla ◽

Suman Nagpal

Keyword(s):

Diabetes Mellitus ◽

Mass Spectrometry ◽

Gas Chromatography ◽

Drug Users ◽

Coefficient Of Determination ◽

Gas Chromatography Mass Spectrometry ◽

Biological Matrices ◽

Chromatography Mass Spectrometry ◽

Ms Analysis ◽

The Stability

Abstract Background Recent advances in the diversified anti-diabetic drugs have appeared in the startling increase in the count of poisoning cases. The epidemics of diabetes mellitus are increasing; hence, the no. of anti-diabetic drug users raised by 42.9%. The use of glimepiride raised to 24%. As the toxicity and drug cases are also escalating with increasing epidemics of diabetes mellitus, a novel gas chromatography-mass spectrometry (GC-MS) method for detecting glimepiride in biological matrices is developed. Results Liquid-liquid extraction method was employed by using 1-butanol: hexane (50:50, v/v) under an alkaline medium, and then back extraction was done via acetic acid. Distinct derivatization techniques were employed for the sample preparation for GC-MS analysis, i.e., silylation and acylation. Derivatization approaches were optimized under different parameters, i.e., reaction temperature and reaction time. N-Methyl-N-(trimethylsilyl) trifluoroacetamide [MSTFA] was found to be the best sound derivatization reagent for the GC-MS analysis of glimepiride. Total ion current (TIC) mode was selected for the monitoring of ions of trimethylsilyl (TMS) derivative of glimepiride with an m/z ratio of 256. Distinct parameters like specificity, carryover, stability, precision, and accuracy were evaluated for validating the identification method. The GC-MS method is found to be linear and illustrated within the range 500 to 2500 ng/ml with the value of R2 (coefficient of determination) at 0.9924. The stability of the extracted and derivatized glimepiride was accessed with regard to processed/extracted sample conditions and autosampler conditions, respectively. Accuracy at each concentration level was within the + 15% of the nominal concentration. Precision (%) for the interday and intraday analysis was found to be in the respectable spectrum. Conclusion Henceforth, the proposed GC-MS method can be employed for the determination of glimepiride in biological matrices.

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Stability of Four Steroids in Lyophilised Human Serum

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456328302000607 ◽

1983 ◽

Vol 20 (6) ◽

pp. 364-368 ◽

Cited By ~ 5

Author(s):

Rose E Gaines Das ◽

D H Calam ◽

F L Mitchell ◽

F P Woodford ◽

Marion Cawood ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Reference Material ◽

Ambient Temperature ◽

Human Serum ◽

Deleterious Effect ◽

Gas Chromatography Mass Spectrometry ◽

Accelerated Degradation ◽

Assay Methods ◽

The Stability

The stability of a preparation of lyophilised serum and its suitability for use as a reference material for routine assays of Cortisol, oestradiol, and progesterone have been studied in four laboratories with a variety of assay systems. Cortisol and oestradiol were also measured by gas chromatography-mass spectrometry. The lyophilised serum was suitable for use in all routine and reference assay methods examined, with between-method variability no greater than that for frozen serum pools. The concentrations of Cortisol, oestradiol, and progesterone were predicted by accelerated degradation studies to decline by 0·01% per annum if the preparations were to be stored at —20°C. The testosterone content of the preparation, determined in one laboratory, provided no evidence for degradation. The preparation can be shipped for use at ambient temperature without deleterious effect.

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Towards understanding of electrolyte degradation in lithium-mediated non-aqueous electrochemical ammonia synthesis with gas chromatography-mass spectrometry

RSC Advances ◽

10.1039/d1ra05963g ◽

2021 ◽

Vol 11 (50) ◽

pp. 31487-31498

Author(s):

Rokas Sažinas ◽

Suzanne Zamany Andersen ◽

Katja Li ◽

Mattia Saccoccio ◽

Kevin Krempl ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Ammonia Synthesis ◽

Gas Chromatography Mass Spectrometry ◽

Ammonia Production ◽

Organic Electrolytes ◽

Electrochemical Systems ◽

Chromatography Mass Spectrometry ◽

The Stability

Lithium-mediated non-aqueous electrochemical ammonia synthesis (LiMEAS) as an efficient and green ammonia production way was studied by GCMS in different organic electrolytes to evaluate the stability of electrochemical systems.

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