Complex of bismuth, an anti-inflammatory drug, was studied by EPR spectroscopy. The aim of this study was to determine concentrations and properties of free radicals formed during thermal sterilization of bismuth subgallate according to pharmacopoeia norms to optimize its sterilization process. Different temperatures (160°C, 170°C, and 180°C) and times (120 minutes, 60 minutes, and 30 minutes) of sterilization were used. Interactions of bismuth subgallate with DPPH, the model free radical reference, were checked. g-Factors, amplitudes (A), integral intensities (I), and linewidths (ΔB pp) were obtained. Integral intensities were obtained by double integration of the first-derivative EPR lines. The influence of microwave power in the range of 2.2-70 mW on shape and parameters of the EPR spectra was examined. Thermal sterilization produced free radicals in bismuth subgallate in all tested cases. Strong interactions with free radicals were pointed out for all the analysed samples containing bismuth independent of sterilization conditions. Optimal conditions of thermal sterilization for bismuth subgallate with the lowest free radical formation are temperature 170°C and time of heating 60 minutes. Strong dipolar interactions exist in thermally sterilized bismuth subgallate. EPR spectroscopy is a useful method of examination of thermal sterilization conditions.

中文翻译：

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热处理过的次镓酸铋的电子顺磁共振研究。

通过EPR光谱研究了一种消炎药铋的复合物。这项研究的目的是根据药典规范确定碱式没食子酸铋热灭菌过程中形成的自由基的浓度和性质，以优化其灭菌过程。使用不同的温度（160°C，170°C和180°C）和消毒时间（120分钟，60分钟和30分钟）。检验了没食子酸铋与模型参考自由基DPPH的相互作用。获得了g因子，振幅（A），积分强度（I）和线宽（ΔBpp）。通过一阶导数EPR线的双重积分获得积分强度。研究了2.2-70 mW范围内的微波功率对EPR谱的形状和参数的影响。在所有测试情况下，热灭菌都会在碱式gal酸铋中产生自由基。指出了所有与铋无关的，与灭菌条件无关的样品中与自由基的强相互作用。具有最低自由基形成的碱式gal酸铋的热灭菌的最佳条件是温度为170°C，加热时间为60分钟。热灭菌的次加仑酸铋中存在强的偶极相互作用。EPR光谱是检查热灭菌条件的有用方法。具有最低自由基形成的碱式gal酸铋的热灭菌的最佳条件是温度为170°C，加热时间为60分钟。热灭菌的次加仑酸铋中存在强的偶极相互作用。EPR光谱是检查热灭菌条件的有用方法。具有最低自由基形成的碱式gal酸铋的热灭菌的最佳条件是温度为170°C，加热时间为60分钟。热灭菌的次加仑酸铋中存在强的偶极相互作用。EPR光谱是检查热灭菌条件的有用方法。