A method based on matrix solid-phase dispersion extraction followed by ultra high performance liquid chromatography with tandem mass spectrometry is presented for the extraction and determination of phenolic compounds in Equisetum palustre. This method combines the high efficiency of matrix solid-phase dispersion extraction and the rapidity, sensitivity, and accuracy of ultra high performance liquid chromatography with tandem mass spectrometry. The influential parameters of the matrix solid-phase dispersion extraction were investigated and optimized. The optimized conditions were as follows: silica gel was selected as dispersing sorbent, the ratio of silica gel to sample was selected to be 2:1 (400/200 mg), and 8 mL of 80% methanol was used as elution solvent. Furthermore, a fast and sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the determination of nine phenolic compounds in E. palustre. This method was carried out within <6 min, and exhibited satisfactory linearity, precision, and recovery. Compared with ultrasound-assisted extraction, the proposed matrix solid-phase dispersion procedure possessed higher extraction efficiency, and was more convenient and time saving with reduced requirements on sample and solvent amounts. All these results suggest that the developed method represents an excellent alternative for the extraction and determination of active components in plant matrices.
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http://dx.doi.org/10.1002/jssc.201400575 | DOI Listing |
H*10 neutron dosimetry (unlike gamma dosimetry), requires consideration of neutron energy spectra due to the 20× variation of the weight factor over the thermal-to-fast energy range, as well as the neutron radiation field dose rates ranging from cosmic, ~.01 μSv h-1 levels to commonly encountered ~10-200 μSv h-1 in nuclear laboratories/processing plants, and upwards of 104 Sv h-1 in nuclear reactor environments. This paper discusses the outcome of the comparison of spectrum-weighted neutron dosimetry covering thermal-to-fast energy using the novel H*-TMFD spectroscopy-enabled sensor system in comparison with measurements using state-of-the-art neutron dosimetry systems at SRNS-Rotating Spectrometer (ROSPEC), and non-spectroscopic Eberline ASP2E ("Eberline") and Ludlum 42-49B ("Ludlum") survey instrumentation.
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Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA.
Although the pathophysiology of migraine involves a complex ensemble of peripheral and central nervous system changes that remain incompletely understood, the activation and sensitization of the trigeminovascular system is believed to play a major role. However, non-invasive, in vivo neuroimaging studies investigating the underlying neural mechanisms of trigeminal system abnormalities in human migraine patients are limited. Here, we studied 60 patients with migraine (55 females, mean age ± SD: 36.
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Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, Sharjah, United Arab Emirates.
Background: Breast cancer is one of the most prevalent malignancies and a leading cause of death among women worldwide. Among its subtypes, triple-negative breast cancer (TNBC) poses significant clinical challenges due to its aggressive behavior and limited treatment options. This study aimed to investigate the effects of doxorubicin (DOX) and 5-fluorouracil (5-FU) as monotherapies and in combination using an established MDA-MB-231 xenograft model in female BALB/C nude mice employing advanced metabolomics analysis to identify molecular alterations induced by these treatments.
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January 2025
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China.
Organic-inorganic hybrid perovskites (OIHPs) have shown great potential for direct X-ray detection in security screening and medical diagnostics. However, their humidity stability is compromised due to the susceptibility of the structural components to water molecules, thereby limiting their practical application. In this work, stable and sensitive X-ray detection is achieved using high-quality bulk single crystals of the 3D perovskitoid (DMPZ)PbBr (DPB, DMPZ = N,N'-dimethyl-pyrazinium), wherein N-acid protons are replaced with hydrophobic alkyl groups.
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Pharmaceutical Chemistry Department, Faculty of Pharmacy, Nahda University, Sharq El-Nile, Beni-Suef, 62511, Egypt.
The study of green analytical chemistry has garnered significant attention in the context of mitigating global environmental contamination. In this study, we present two methodologies for environmentally friendly chromatography that enable simultaneous and specific determination of Saxagliptin (SAX), metformin (MET), and a pharmacopoeial impurity of MET known as melamine (MEL). The initial method employed in this study is High-Performance Thin Layer Chromatography (HPTLC), which utilized 60 F 254 silica gel-coated Mark HPTLC plates on aluminum sheets as the stationary phase.
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