A new atmospheric pressure ionization (API) source, viz. UniSpray, was evaluated for mass spectrometry (MS) analysis of pharmaceutical compounds by head-to-head comparison with electrospray ionization (ESI) on the same high-resolution MS system. The atmospheric pressure ionization source is composed of a grounded nebulizer spraying onto a high voltage, cylindrical stainless steel target. Molecules are ionized in a similar fashion to electrospray ionization, predominantly producing protonated or deprotonated species. Adduct formation (e.g., proton and sodium adducts) and in-source fragmentation is shown to be almost identical between the two sources. The performance of the new API source was compared with electrospray by infusion of a mix of 22 pharmaceutical compounds with a wide variety of functional groups and physico-chemical properties (molecular weight, logP, and pKa) in more than 100 different conditions (mobile phase strength, solvents, pH, and flow rate). The new API source shows an intensity gain of a factor 2.2 compared with ESI considering all conditions on all compounds tested. Finally, some hypotheses on the ionization mechanism, similarities, and differences with ESI, are discussed. Graphical Abstract ᅟ.
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http://dx.doi.org/10.1007/s13361-016-1537-3 | DOI Listing |
Nat Commun
January 2025
Department of Chemistry, University of Toronto, Toronto, ON, Canada.
As the global quest for sustainable energy keeps rising, exploring novel efficient and practical photocatalysts remains a research and industrial urge. Particularly, metal organic frameworks were proven to contribute to various stages of the carbon cycle, from CO capture to its conversion. Herein, we report the photo-methanation activity of three isostructural, nickel-based metal organic frameworks incorporating additional niobium, iron, and aluminum sites, having demonstrated exceptional CO capture abilities from thin air in previous reports.
View Article and Find Full Text PDFJ Intensive Care Med
January 2025
Anand Pharmacy College, Anand, Gujarat, India.
Hyperbaric Oxygen Therapy (HBOT) is a medical treatment that involves administering 100% oxygen at increased atmospheric pressure to enhance oxygen delivery to tissues. Initially developed for decompression sickness, HBOT has since been utilized for a wide range of medical conditions, including severe infections, non-healing wounds, and, more recently, COVID-19. This review explores the historical development of HBOT, its principles, its emerging role in the management of and its outcome as treatment in COVID-19, particularly in mitigating inflammation, hypoxemia, and oxidative stress.
View Article and Find Full Text PDFChem Asian J
January 2025
Indian Institute of Technology Ropar, Chemistry, Nangal Road, 140001, Rupnagar, INDIA.
Carbon dioxide (CO2) capture and its subsequent catalytic fixation into usable compounds represent a potential approach for addressing the energy problem and the implications of global warming. Hence, it is necessary to develop effective catalytic systems required for the transformation of CO2 into valuable chemicals/fuels. Herein, we rationally designed a hydroxyl-functionalized porous organic framework (OH-POF) consisting of both acidic (OH) as well as basic N sites for the transformation of CO2 using epoxides for the production of cyclic carbonates (CCs), a useful commodity chemical under environmental-friendly, metal/solvent/co-catalyst-free conditions.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Biotechnology, University of Verona, Verona, Italy.
Lower atmospheric pressure affects biologically relevant physical parameters such as gas partial pressure and concentration, leading to increased water vapor diffusivity and greater soil water content loss through evapotranspiration. This might impact plant photosynthetic activity, resource allocation, water relations, and growth. However, the direct impact of low air pressure on plant physiology is largely unknown.
View Article and Find Full Text PDFJ Chem Eng Data
January 2025
LATA2M, Laboratoire de Thermodynamique Appliquée et Modélisation Moléculaire, University of Tlemcen, Post Office Box 119, Tlemcen 13000, Algeria.
The density (ρ), speed of sound (), and refractive index ( ) of ,-dimethylacetamide (DMA) with 1-butanol, 1-pentanol, furfural (FFL), or furfuryl alcohol (FA) as a function of composition and at = 293.15 to 323.15 K with an interval of 10 K and atmospheric pressure were measured.
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