Determination of fat and water content in vitro and in vivo by proton nuclear magnetic resonance

1991 ◽  
Vol 56 (3) ◽  
pp. 265-276 ◽  
Author(s):  
Alva D Mitchell ◽  
Theodore H Elsasser ◽  
Paul C Wang
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Water Content ◽  
Proton Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

scholarly journals N-[7-Chloro-4-[4-(phenoxymethyl)-1H-1,2,3-triazol-1-yl] quinoline]-acetamide

Molbank ◽  
10.3390/m1213 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1213
Author(s):  
Paolo Coghi ◽  
Jerome P. L. Ng ◽  
Ali Adnan Nasim ◽  
Vincent Kam Wai Wong
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Quantum Coherence ◽  
Biologically Active ◽  
Proton Nuclear Magnetic Resonance ◽  
Dipolar Cycloaddition ◽  
Heteronuclear Single Quantum Coherence ◽  
Pharmacokinetic Properties ◽  
Nuclear Magnetic

The 1,2,3-triazole is a well-known biologically active pharmacophore constructed by the copper-catalyzed azide–alkyne cycloaddition. We herein reported the synthesis of 4-amino-7-chloro-based [1,2,3]-triazole hybrids via Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition of 4-azido-7-chloroquinoline with an alkyne derivative of acetaminophen. The compound was fully characterized by Fourier-transform infrared (FTIR), proton nuclear magnetic resonance (1H-NMR), carbon-13 nuclear magnetic resonance (13C-NMR), heteronuclear single quantum coherence (HSQC), ultraviolet (UV) and high-resolution mass spectroscopies (HRMS). This compound was screened in vitro with different normal and cancer cell lines. The drug likeness of the compound was also investigated by predicting its pharmacokinetic properties.

Determination of Ephedrine, Pseudoephedrine, and Norephedrine in Mixtures (Bulk and Dosage Forms) by Proton Nuclear Magnetic Resonance Spectroscopy

1995 ◽  
Vol 78 (4) ◽  
pp. 946-953 ◽  
Author(s):  
George M Hanna
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Spectroscopic Method ◽  
Internal Standard ◽  
Dosage Forms ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
1H Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

Abstract A simple, specific, and accurate 1H nuclear magnetic resonance (NMR) spectroscopic method has been developed for quantitative determination of the Ephedra alkaloids (−)-ephedrine, (+)-pseudoephedrine, and (±)-norephedrine, either singly or in mixtures with each other. Determination of individual alkaloids was carried out in D2O solution, with acetamide as internal standard. Although calculations were based on integrals for the C–CH3 protons, those for the N–CH3 and –CH–O– protons may also be useful, depending on the compound. Determination of diastereomeric cross-contamination of ephedrine and pseudoephedrine—or of the concentrations of these alkaloids in the presence or absence of (±)-norephedrine—was feasible by using the integrals for the –CH–O– protons after addition of a trace of DCI. Mean recoveries for ephedrine and pseudoephedrine from their respective synthetic mixtures with the internal standard (acet- amide) were ≥99.9 ± 0.6% (n = 10) and 99.6 ± 0.8% (n = 10) of the amount added. Recovery for pseudoephedrine from diastereomeric mixtures with ephedrine was >99.4 ± 0.7% (n = 10) of the amount added, with as little as 1.92% still being measurable. Mean recovery of (±)-norephedrine from mixtures with ephedrine and pseudoephedrine was >99.7 ± 2.5% (n = 4) of the amount added, with about 1% still being measurable. Application of the proposed NMR spectroscopic method to commercial dosage forms, including ephedrine sulfate injections and pseudoephedrine hydrochloride tablets, yielded assay results ranging from 97.8 to 100.2% (mean, 99.2%) and from 98.7 to 100.5% (mean, 99.7%) of declared, respectively.

Immunosuppressive activity of cyclosporine metabolites compared and characterized by mass spectroscopy and nuclear magnetic resonance

1990 ◽  
Vol 36 (2) ◽  
pp. 225-229 ◽  
Author(s):  
K R Copeland ◽  
R W Yatscoff ◽  
R M McKenna
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Mass Spectroscopy ◽  
Proton Nuclear Magnetic Resonance ◽  
Therapeutic Monitoring ◽  
Potency Ratio ◽  
Transplant Patients ◽  
In Vitro Systems ◽  
Nuclear Magnetic

Abstract Eight cyclosporine (CsA) metabolites were isolated from the urine of renal-transplant patients by high-pressure liquid chromatography. Structure and purity of the metabolites were assessed by fast atomic bombardment/mass spectroscopy, by proton nuclear magnetic resonance (NMR), and, when the quantity of metabolites permitted, by 13C-NMR. The immunosuppressive activities (I) of the metabolites were tested in three separate in vitro systems: primary and secondary mixed lymphocyte reactions as well as by a mitogen-stimulated system. The I, as measured by comparing the concentration of each metabolite required for 50% inhibition of incorporation of [3H] thymidine, varied among the assay systems, as did the ranking of I among the test systems. In general, the I of most metabolites in all assay systems were less than 10% of that for CsA. Metabolites with single modifications exhibited the greatest I; e.g., that of M-17 was congruent to 16% of that of CsA (potency ratio 0.16) in a secondary mixed lymphocyte reaction. The significance of these findings in relation to therapeutic monitoring of CsA is discussed.

scholarly journals Risedronate Effects on the In Vivo Bioactive Glass Behavior: Nuclear Magnetic Resonance and Histopathological Studies

2019 ◽  
Vol 2019 ◽  
pp. 1-16
Author(s):  
Siwar Mosbahi ◽  
Hassane Oudadesse ◽  
Claire Roiland ◽  
Bertrand Lefeuvre ◽  
Lotfi Slimani ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Bioactive Glass ◽  
Volume Fraction ◽  
Chemical Reactivity ◽  
Femoral Condyle ◽  
Mineral Density ◽  
Nuclear Magnetic

The present study aimed to enhance the anti-osteoporotic performance of bioactive glass (46S6) through its association with bisphosphonate such as risedronate with amounts of 8, 12, and 20%. Obtained composites have been called 46S6-8RIS, 46S6-12RIS, and 46S6-20RIS, respectively. In vitro and in vivo explorations have been carried out. Bioactive glass and risedronate association has been performed by adsorption process. Structure analyses have been carried out to evaluate and to understand their chemical interactions. Solid Nuclear Magnetic Resonance (NMR) has been employed to study the structural properties of obtained biocomposite. The spectra deconvolution showed the appearance of a species (Q4) in the biocomposites 46S6-8RIS, 46S6-12RIS, and 46S6-20RIS indicating their successful chemical association. In vitro experiments showed the enhancement of the chemical reactivity of the composites 46S6-xRIS compared to the pure bioactive glass. In fact, the silicon liberation after 30 days of immersion was 50 ppm for pure bioactive glass 46S6, and 41, 64, and 62 from 46S6-8RIS, 46S6-12RIS, and 46S6-20RIS, respectively. Based on the in vitro results, 46S6-8RIS was implanted in the femoral condyle of an ovariectomized rat and compared with implanted pure glass in the goal to highlight its anti-osteoporotic performance. After 60 days, implanted group with 46S6-8RIS showed the increase in bone mineral density (BMD with 10%) and bone volume fraction (BV/TV with 80%) and the decrease in trabecular separation (Tb/Sp with 74%) when compared to that of 46S6 group. These results are confirmed by the histopathological analyses, which showed the bone trabeculae reconnection after the 46S6-8RIS implantation. Chemical analyses showed the reduction in silicon (Si) and sodium (Na) ion concentrations, and the rise in calcium (Ca) and phosphorus (P) ion levels, which was explained by the dissolution of biocomposite matrix and the deposition of hydroxyapatite layer. Histomorphometric results highlighted the risedronate effect on the antiosteoporotic phenomenon. Obtained results showed good behavior with only 8% of introduced risedronate in the glass matrix.

Sign in / Sign up

Export Citation Format

Share Document