Search results for "SPECTROMETRY"
showing 10 items of 3206 documents
A fluorescence study of the loading and time stability of doxorubicin in sodium cholate/PEO-PPO-PEO triblock copolymer mixed micelles
2019
Abstract Hypothesis Doxorubicin hydrochloride (DX) is one of the most powerful anticancer agents though its clinical use is impaired by severe undesired side effects. DX encapsulation in nanocarrier systems has been introduced as a mean to reduce its toxicity. Micelles of the nonionic triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) (PEO-PPO-PEO), are very promising carrier systems. The positive charge of DX confines the drug to the hydrophilic corona region of the micelles. The use of mixed micelles of PEO-PPO-PEO copolymers and a negatively charged bile salt should favour the solubilization of DX in the apolar core region of the micelles. Experiments We st…
Assays for detection of fungal hallucinogens such as psilocybin and psilocin
2016
Methods applicable to the detection of hallucinogenic indole compounds, namely psilocybin, psilocin, and related molecules, that have been developed so far for purposes of mycological research, toxicological studies, or forensic investigations are described in this chapter. The most current literature as well as some interesting older publications are cited, providing a historical overview of the subject. Methods of qualitative and quantitative analysis are presented. Additionally, preliminary purification steps and sample treatment before the exact quantitative determination are proposed. The methods described utilized various analytical techniques for the measurement of psilocybin/psiloci…
Preliminary Investigation of Biogenic Amines in Type I Sourdoughs Produced at Home and Bakery Level
2022
During a survey for isolating sourdough lactic acid bacteria (LAB), 20 dough samples produced at the bakery level (BL) or home-made (HM) were collected. An enzyme-based colorimetric method revealed a total biogenic amines (BAs) concentration in the range 41.4–251.8 ppm for six (three BL and three HM) sourdoughs characterised by unpleasant odours. Eight BAs generally investigated in foods were identified and quantified from these six samples by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). Only one HM sample contained almost all analysed BAs. Tryptamine was exclusively detected in HM sourdoughs (0.71–24.1 ppm). Putrescine, tryptamine, …
Pd2Au36(SR)(24) cluster: structure studies
2015
The location of the Pd atoms in Pd2Au36(SC2H4Ph)(24), is studied both experimentally and theoretically. X-ray photoelectron spectroscopy (XPS) indicates oxidized Pd atoms. Palladium K-edge extended X-ray absorption fine-structure (EXAFS) data clearly show Pd-S bonds, which is supported by far infrared spectroscopy and by comparing theoretical EXAFS spectra in R space and circular dichroism spectra of the staple, surface and core doped structures with experimental spectra.
Data set: Towards a rapid screening of liver grafts at the operating room using mid-infrared spectroscopy
2020
The estimation of steatosis in a liver graft is mandatory prior to liver transplantation, as the risk of graft failure increases with the level of infiltrated fat. However, the assessment of liver steatosis before transplantation is typically based on a qualitative or semi-quantitative characterization by visual inspection and palpation, and histological analysis. Thus, there is an unmet need for transplantation surgeons to have access to a diagnostic tool enabling an in situ fast classification of grafts prior extraction. In this study, we have assessed an Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopic method compatible with the requirements of an operation…
Data set: Towards a rapid screening of liver grafts at the operating room using mid-infrared spectroscopy
2020
The estimation of steatosis in a liver graft is mandatory prior to liver transplantation, as the risk of graft failure increases with the level of infiltrated fat. However, the assessment of liver steatosis before transplantation is typically based on a qualitative or semi-quantitative characterization by visual inspection and palpation, and histological analysis. Thus, there is an unmet need for transplantation surgeons to have access to a diagnostic tool enabling an in situ fast classification of grafts prior extraction. In this study, we have assessed an Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopic method compatible with the requirements of an operation…
Data set: Towards a rapid screening of liver grafts at the operating room using mid-infrared spectroscopy
2020
The estimation of steatosis in a liver graft is mandatory prior to liver transplantation, as the risk of graft failure increases with the level of infiltrated fat. However, the assessment of liver steatosis before transplantation is typically based on a qualitative or semi-quantitative characterization by visual inspection and palpation, and histological analysis. Thus, there is an unmet need for transplantation surgeons to have access to a diagnostic tool enabling an in situ fast classification of grafts prior extraction. In this study, we have assessed an Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopic method compatible with the requirements of an operation…
The effect of defect location on coating fragmentation patterns under biaxial tension
2005
Fragmentation of a coating possessing orthogonal preferential crack propagation directions is modeled for equibiaxial tensile loading. Two plausible cracking scenarios are compared, caused by flaws randomly distributed over the area of the coating or along the coating fragment edges. The two fragmentation scenarios considered are shown to yield qualitatively different fragment patterns.
Studies in organic mass spectrometry. Part 23. Role of the aroyl group on the competitive fragmentation reactions of the molecular ion of aroylanilid…
1999
The 70 eV and mass-analysed ion kinetic energy (MIKE) spectra of some thiophenecarboxanilides and benzoylanilides (1–10) have been compared in order to investigate the role of the aroyl (or heteroaroyl) moiety on the abundance of the competitive fragmentation reactions occurring in their molecular ions (amide–bond cleavage and phenol radical ion formation). It has been shown that the electron ionisation induced decompositions with high (70 eV) and low (MIKE) internal energy excess are qualitatively similar, but remarkable quantitative differences have been observed that can be accounted for in terms of the different effectiveness in the transmission of electronic effects of substituents in …
Surfactant self-assembling in the gas phase: bis(2-ethylhexyl)- sulfosuccinate divalent metal ion anionic aggregates
2012
RATIONALE: Investigation of fundamental aspects driving surfactant self-assembling and of the capability of including guest molecules or ions in their micellar aggregates is an exciting research field for theoretical and technological reasons. In this light, assembling and chelating properties of sodium bis(2-ethylhexyl)sulfosuccinate (AOTNa) towards divalent metal ion chlorides have been investigated in the gas phase by electrospray ionization mass spectrometry in negative ion mode, tandem mass spectrometry and energy-resolved mass spectrometry. METHODS:Water/methanol solutions of AOTNa and chloride salts of nickel, magnesium, calcium and manganese, with different AOTNa/metal salt ratios, …