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1.
China Tropical Medicine ; (12): 260-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979627

RESUMO

@#Abstract: Objective To investigate a poisoning incident caused by eating eight treasure congee, and establish liquid chromatography (LC)-mass spectrometry (MS)/MS screening method of 28 alkaloids to provide references for disposal of similar poisoning incidents. Methods LC-MS/MS was used for screening 28 alkaloids in the urine, eight treasure congee and food raw material, and the detected alkaloids were quantified. Samples were extracted with 0.4% formic acid aqueous solution and separated by a Acquity UPLC BEH C18 column (1.7 μm, 100 × 2.1 mm). Acetonitrile-0.2% formic acid aqueous solution was used as the mobile phase and gradient elution was adopted. The ionization mode was electrospray positive ionization mode, and the detection method was multi-reaction monitoring (MRM). Analytes were quantified with the external standard method. Results In the concentration range of 0-100 ng/mL, the linear correlation coefficient r were greater than 0.999 for 28 alkaloids. The recovery of 28 alkaloids in urine sample ranged from 63.0% to 105.0%, and the relative standard deviations (RSDs) were between 5.8% and 8.6%. The recovery of 28 alkaloids in eight treasure congee sample ranged from 72.0% to 109.0%, and the RSDs were between 6.3% and 9.7%. The recovery of 28 alkaloids in semen sesami nigrum sample ranged from 60.0% to 95.0%, and the RSDs were between 4.8% and 8.2%. Hyoscyamine (2 380.0 ng/mL), scopliamine (3.6 ng/mL) and rac-anisodamine (4.7 ng/mL) were detected in the patient's urine. Hyoscyamine (63.3 μg/g), scopliamine (5.7 μg/g) and rac-anisodamine (2.1 μg/g) were detected in eight treasure congee. Hyoscyamine (901.0 μg/g), scopliamine (80.0 μg/g) and rac-anisodamine (30.1 μg/g) were detected in the seed of Datura stramonium L. The ratio of scopliamine and hyoscyamine in the seed of D. stramonium was 1∶11, which complies with the characteristics of D. stramonium L. In urine sample, the proportion of scopliamine and rac-anisodamine was 0.15% and 0.20%, and hyoscyamine accounted for 99.65%. Conclusion Seed morphology, the content range and proportion of three alkaloids are all in accord with the characteristics of D. stramonium. Combined with the clinical symptoms of atropine poisoning, it can be deduced that this incident is a family food poisoning caused by accidental consumption of seed of D. stramonium L. The method can provide technical support for the clinical diagnosis and treatment of alkaloid poisoning patients, and also provide a basis for emergency detection and disposal of alkaloid poisoning events.

2.
J Am Chem Soc ; 132(20): 7069-73, 2010 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-20426474

RESUMO

The new oxyselenide La(2)Co(2)Se(2)O(3), containing Co(2)O square-planar layers, has been successfully synthesized using solid-state reactions under vacuum. The compound crystallizes in space group I4/mmm with lattice parameters a = 4.0697(8) A and c = 18.419(4) A. Magnetic susceptibility measurements indicate an antiferromagnetic transition at approximately 220 K. The magnetic entropy associated with the transition is close to R ln 2, suggesting an unusual low-spin state for the Co(2+) ions. The as-prepared sample shows insulating behavior with room-temperature resistivity of approximately 10(7) ohms cm, which decreases by 4 orders of magnitude under a pressure of 7 GPa. Band structure calculations using the LSDA+U approach reproduce the insulating ground state with low spin for Co and suggest strong orbital polarization for the valence electrons near the Fermi level. It is also revealed that the spin and orbital degrees of freedom in the antiferromagnetic checkerboard spin-lattice are mutually coupled.

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