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1.
Huan Jing Ke Xue ; 45(3): 1265-1273, 2024 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-38471843

RESUMEN

To quantitatively evaluate the co-benefits of air pollution reduction and carbon dioxide reduction of Taiyuan's 14th Five-Year Plan air pollution prevention and control policies, this study used the Beijing-Tianjin-Hebei Greenhouse Gas-Air Pollution Interaction and Synergy Model (GAINS-JJJ) to simulate and evaluate the emission reduction potential and CO2 co-benefit of 13 air pollution control measures. The emission reductions of PM2.5, PM10, SO2, NOx, VOCs, and NH3 in 2025 were 1.8 (5%, compared with that in the baseline scenario), 2.5 (2%), 3.7 (16%), 20.0 (27%), 13.6 (15%), and 0.0 kt (0%), respectively. The reduction in CO2 emissions was 9.0 Mt (13%), whereas CH4 emissions increased by 203.3 kt (25% increase relative to that in the baseline scenario). SO2, NOx, and VOCs emission reductions derived from the power, industrial combustion, and solvent use sectors. CO2 reduction occurred mainly in the industrial combustion sector, and CH4 emission increased mainly due to the increase in coal mining activity. The highest synergistic CO2 reductions were achieved by restricting energy consumption in the high energy-consuming and high-emitting sectors; prohibiting new capacity in the steel, coke, cement, and flat glass industries; and replacing coal-fired power generation with renewable energy. Furthermore, the CO2 reduction co-benefit was highest for VOCs. In addition, this study suggests that promoting the policy of terminal electrification and simultaneously increasing the share of clean energy and the ability to consume renewable energy generation in the power sector are the keys to decreasing the emissions in Taiyuan.

2.
J Pharm Biomed Anal ; 241: 116000, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38280234

RESUMEN

An increasing number of drug research institutions consider genotoxic impurity research a core task in drug research and development. Peroxides in drugs may directly or indirectly attack and damage cell DNA, posing a potential carcinogenic risk to the human body. Currently, the literature only studies hydroperoxide impurities, and benzyl peroxide has not been studied yet. In this study, an effective method for ultra-performance liquid chromatographymass spectrometry (UPLCMS/MS) was established and verified to detect and quantify the potential genotoxic impurity (PGI), empagliflozin benzyl peroxide, in metformin-empagliflozin combination formulations, which has not been reported thus far. A Waters ACQUITY UPLC HSS T3 (3.0 ×100 mm, 1.8 µm) column was used to achieve chromatographic separation with gradient elution. The mass spectrometry conditions were optimized using electrospray ionization in the negative mode. Following the International Conference of Harmonization (ICH) guidelines, this methodology can quantify PGIs at 1.35 ng/mL (5.4 ppm) in samples. This validated method exhibited good linearity over a concentration range of 5.4 to 36 ppm, and the accuracy of this method was in the range of 83.2-95.0% for empagliflozin benzyl peroxide. This approach fills the gap in the detection method for benzyl peroxide impurities in metformin hydrochloride and empagliflozin tablets, providing technical support for the quality control of the drug.


Asunto(s)
Compuestos de Bencidrilo , Glucósidos , Metformina , Humanos , Metformina/análisis , Cromatografía Líquida de Alta Presión/métodos , Análisis Espectral , Comprimidos , Peróxidos
3.
Biomed Chromatogr ; 38(2): e5790, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38158853

RESUMEN

In the production of doxofylline, the common occurrence of toxic p-toluene sulfonate generation prompted the development and validation of a method using HPLC with ultraviolet detection (HPLC-UV). This method is designed for detecting four potential genotoxic impurities (PGIs) present in both doxofylline drug substance and tablets, with a focus on the UV-absorbing group p-toluene sulfonate. The four impurities were methyl 4-methylbenzenesulfonate (PGI-1), ethyl 4-methylbenzenesulfonate (PGI-2), 2-hydroxyethyl 4-methylbenzenesulfonate (PGI-3), and 2-(4-methylphenyl)sulfonyloxyethyl 4-methylbenzenesulfonate (PGI-4). In this method, chromatographic separation was achieved using a Waters Symmetry C18 column (250 mm × 4.6 mm, 5 µm). The mobile phases consisted of 20% acetonitrile as mobile phase A and pure acetonitrile as mobile phase B, operating in gradient elution mode at a flow rate of 1.0 mL/min. According to the guidelines of the International Conference on Harmonization, it was determined that this method could quantify four PGIs at 0.0225 µg/mL in samples containing 60 mg/mL. The validated approach demonstrated excellent linearity (R2 > 0.999) across the concentration range of 30%-200% (relative to 0.075 µg/mL doxofylline) for the four PGIs. The accuracy of this method for the four PGIs ranged from 94.8% to 100.4%. The reverse-phase-HPLC-UV analytical method developed in this study is characterized by its speed and precision, making it suitable for the sensitive analysis of benzene sulfonate PGIs in doxofylline drug substances and tablets.


Asunto(s)
Benceno , Bencenosulfonatos , Medicamentos a Granel , Teofilina/análogos & derivados , Cromatografía Líquida de Alta Presión/métodos , Comprimidos/química , Acetonitrilos
4.
J Nanobiotechnology ; 16(1): 65, 2018 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-30205821

RESUMEN

BACKGROUND: Due to the high transfer ability of cancer cell, cancer has been regarded as a world-wide high mortality disease. Quantitative analysis of circulating tumor cells (CTCs) can provide some valuable clinical information that is particularly critical for cancer diagnosis and treatment. Along with the rapid development of micro-/nano-fabrication technique, the three-dimensional (3D) bionic interface-based analysis method has become a hot research topic in the area of nanotechnology and life science. Micro-/nano-structure-based devices have been identified as being one of the easiest and most effective techniques for CTCs capture applications. METHODS: We demonstrated an electrospun nanofibers-deposited nickel (Ni) micropillars-based cytosensor for electrochemical detection of CTCs. Breast cancer cell line with rich EpCAM expression (MCF7) were selected as model CTCs. The ultra-long poly (lactic-co-glycolic acid) (PLGA) nanofibers were firstly-crosswise stacked onto the surface of Ni micropillars by electrospinning to construct a 3D bionic interface for capturing EpCAM-expressing CTCs, following immuno-recognition with quantum dots functionalized anti-EpCAM antibody (QDs-Ab) and forming immunocomplexes on the micro-/nano-chip. RESULTS: The Ni micropillars in the longitudinal direction not only play a certain electrical conductivity in the electrochemical detection, but also its special structure improves the efficiency of cell capture. The cross-aligned nanofibers could simulate the extracellular matrix to provide a good microenvironment which is better for cell adhesion and physiological functions. Bioprobe containing quantum dots will release Cd2+ in the process of acid dissolution, resulting in a change in current. Beneath favourable conditions, the suggested 3D cytosensor demonstrated high sensitivity with a broad range of 101-105 cells mL-1 and a detection limit of 8 cells mL-1. CONCLUSIONS: We constructed a novel 3D electrochemical cytosensor based on Ni micropillars, PLGA electrospun nanofibers and quantum dots bioprobe, which could be used to highly sensitive and selective analysis of CTCs. More significantly, the 3D cytosensor can efficiently identify CTCs from whole blood, which suggested the potential applications of our technique for the clinical diagnosis and therapeutic monitoring of cancers.


Asunto(s)
Técnicas Biosensibles/instrumentación , Neoplasias de la Mama/diagnóstico , Dispositivos Laboratorio en un Chip , Nanofibras/química , Células Neoplásicas Circulantes/patología , Níquel/química , Puntos Cuánticos/química , Anticuerpos Inmovilizados/química , Neoplasias de la Mama/patología , Separación Celular/instrumentación , Técnicas Electroquímicas/instrumentación , Molécula de Adhesión Celular Epitelial/análisis , Diseño de Equipo , Femenino , Humanos , Células MCF-7 , Nanofibras/ultraestructura , Nanotecnología/instrumentación , Puntos Cuánticos/ultraestructura
5.
Nanoscale ; 7(39): 16354-60, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26391313

RESUMEN

Determination of the presence and number of circulating tumor cells (CTCs) in peripheral blood can provide clinically important data for prognosis and therapeutic response patterns. In this study, a versatile supersandwich cytosensor was successfully developed for the highly sensitive and selective analysis of CTCs using Au-enwrapped silica nanocomposites (Si/AuNPs) and three-dimensional (3D) microchips. First, 3D microchips were fabricated by a photolithography method. Then, the prepared substrate was applied to bind graphene oxide, streptavidin and biotinylated epithelial-cell adhesion-molecule antibody, resulting in high stability, bioactivity, and capability for CTCs capture. Furthermore, horseradish peroxidase and anti-CA153 were co-linked to the Si/AuNPs for signal amplification. The performance of the cytosensor was evaluated with MCF7 breast cancer cells. Under optimal conditions, the proposed supersandwich cytosensor showed high sensitivity with a wide range of 10(1) to 10(7) cells per mL and a detection limit of 10 cells per mL. More importantly, it could effectively distinguish CTCs from normal cells, which indicated the promising applications of our method for the clinical diagnosis and therapeutic monitoring of cancers.


Asunto(s)
Técnicas Biosensibles , Oro , Grafito , Dispositivos Laboratorio en un Chip , Nanocompuestos , Células Neoplásicas Circulantes , Dióxido de Silicio , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Femenino , Humanos , Células MCF-7 , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patología
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