Rapid determination of ATP, ADP, AMP and phosphate in drug by 31P NMR spectroscopy / 药学学报

The content of ATP, ADP, AMP, sodium phosphate and sodium pyrophosphate were determined by 31P NMR, the linear range of ATP, ADP and AMP were found to be 0.004-0.080 mol x L(-1), sodium phosphate and sodium pyrophosphate were 0.005-0.100 mol x L(-1). The RSD were 0.40%-1.30%, the recovery were 96.9% - 105.2%. The method has been applied to the determination of ATP injection. The impurities of ATP injection were ADP and sodium phosphate. The content of ATP is in line with the requirement of the pharmacopoeia. The results indicated that the method is of good reproducibility, high accuracy, rapid and simple operation, without pretreatment and interference of other elements, 31P NMR is a new and reliable method of analyzing ATP, ADP, AMP and phosphate.

[Effect of pulmonary surfactant on Th1/Th2 balance in neonates with respiratory distress syndrome].

OBJECTIVE: To investigate the effect of pulmonary surfactant (PS) on the Th1/Th2 balance and serum levels of interleukin-4 (IL-4), interferon-γ (IFN-γ) and IgE in neonates with respiratory distress syndrome (RDS). METHODS: A total of 58 neonates with RDS were divided into control (n=20) and PS treatment groups (n=38). The control group underwent mechanical ventilation and other conventional treatment, while the PS treatment group received with bovine PS treatment within 1 hour of being admitted to the hospital together with mechanical ventilation and other conventional treatment. Enzyme-linked immunosorbent assay was used to measure serum levels of IL-4, IFN-γ and IgE before treatment and 24, 48 and 72 hours after treatment. Simultaneously, arterial blood gas, respiratory system compliance, and other ventilator parameters were recorded. RESULTS: Compared with the control group, the PS treatment group showed significantly shorter duration of mechanical ventilation and oxygen exposure time (P<0.05), significantly better respiratory system compliance and significantly lower oxygenation index 24, 48 and 72 hours after treatment (P<0.05). At 48 and 72 hours after treatment, serum levels of IFN-γ were significantly lower in the PS treatment group than in the control group (120±46 ng/L vs 229±59 ng/L, P<0.05; 141±40 ng/L vs 282±44 ng/L, P<0.05), and serum levels of IL-4 were significantly higher in the PS treatment group than in the control group (263±48 pg/mL vs 152±45 pg/mL, P<0.05; 417±49 pg/mL vs 201±46 pg/mL, P<0.05). At 72 hours after treatment, serum level of IgE was significantly lower in the PS treatment group than in the control group (115±44 pg/mL vs 199±43 ng/mL; P<0.05). CONCLUSIONS: PS treatment can shorten the duration of mechanical ventilation and oxygen exposure time, regulate serum levels of IFN-γ, IL-4 and IgE, and influence Th1/Th2 balance in neonates with RDS, thus inhibiting lung inflammatory response and reducing lung injury.

Experimental free-space distribution of entangled photon pairs over 13 km: towards satellite-based global quantum communication.

We report free-space distribution of entangled photon pairs over a noisy ground atmosphere of 13 km. It is shown that the desired entanglement can still survive after both entangled photons have passed through the noisy ground atmosphere with a distance beyond the effective thickness of the aerosphere. This is confirmed by observing a spacelike separated violation of Bell inequality of 2.45+/-0.09. On this basis, we exploit the distributed entangled photon source to demonstrate the Bennett-Brassard 1984 quantum cryptography scheme. The distribution distance of entangled photon pairs achieved in the experiment is for the first time well beyond the effective thickness of the aerosphere, hence presenting a significant step towards satellite-based global quantum communication.

[Effect of thermal treatment of nanotubed H2Ti2O4 (OH)2 on photoluminescence properties].

The effect of thermal treatment (100 degrees C, -0.1 MPa) of nanotubed H2Ti2O4(OH)2 on photoluminescence properties was investigated. The results showed that the photoluminescence intensity of dehydrated nanotubed H2Ti2O4 (OH)2 increases with the treatment time(t) when t < or = 23 h, and decreases when t > 23 h, which is different from the changes in ESR intensity and absorption with t. It can be explained as follows: When the concentration of single-electron trapped oxygen vacancies (Vo*) generated from dehydration reaches a threshold value, strong interaction will take place between the adjacent Vo*. This will result in decreasing the probability of photoluminescence emission, and increasing the probability of nonradiative transition. So the photoluminescence intensity of dehydrated nanotubed H2Ti2O4 (OH)2 is enhanced first, and then decreases.

[Study on the preparation of nanometer oxide SnO2 gas-sensitive material by sol-gel method].

Based on the sol-gel method, nanosized SnO2 material was prepared, and its structure and properties were studied by XRD, UV and Raman spectra. The XRD result indicated that the SnO2 particles had an ideal nanosize. The diameter of SnO2 particles increased with raising the temperature. The Raman spectrum indicated that the SnO2 nanometer material annealed at low temperature had a large number of O-empties. The UV spectra showed that the sample had stable absorption properties although the particle size changed greatly in the annealed range of 300-500 degrees C. These properties might be utilized in enhancing the performance of SnO2 gas-sensitive devices.