PDF(Pubmed)
Abstract：
The chemical stability of azithromycin (AZM) may be compromised depending on the imposed thermo-oxidative conditions. This report addresses evidence of this process under varying conditions of temperature (20-80 °C), exposure time to UV radiation (1-3 h irradiation at 257 nm), and air saturation (1-3 h saturation with atmospheric air at 1.2 L min-1 and 15 kPa) through electrochemical measurements performed with a thermoactivated cerium molybdate (Ce2(MoO4)3)/multi-walled carbon nanotubes (MWCNT)-based composite electrode. Thermal treatment at 120 °C led to coordinated water elimination in Ce2(MoO4)3, improving its electrocatalytic effect on antibiotic oxidation, while MWCNT were essential to reduce the charge-transfer resistance and promote signal amplification. Theoretical-experimental data revealed remarkable reactivity for the irreversible oxidation of AZM on the working sensor using phosphate buffer (pH = 8) prepared in CH3OH/H2O (10:90%, v/v). Highly sensitive (230 nM detection limit) and precise (RSD < 4.0%) measurements were recorded under these conditions. The results also showed that AZM reduces its half-life as the temperature, exposure time to UV radiation, and air saturation increase. This fact reinforces the need for continuous quality control of AZM-based pharmaceuticals, using conditions closer to those observed during their transport and storage, reducing impacts on consumers\' health.
摘要：
取决于所施加的热氧化条件,阿奇霉素(AZM)的化学稳定性可能受到损害。本报告阐述了在不同温度条件(20-80°C)下这一过程的证据。暴露于紫外线辐射的时间（在257nm下照射1-3小时），通过使用热活化的钼酸铈（Ce2（MoO4）3）/多壁碳纳米管（MWCNT）基复合电极进行的电化学测量，以及空气饱和度（在1.2Lmin-1和15kPa下与大气空气的1-3小时饱和度）。在120°C的热处理导致Ce2（MoO4）3中的协同水消除，从而改善了其对抗生素氧化的电催化作用，而MWCNT对于降低电荷转移电阻和促进信号放大是必不可少的。理论实验数据显示，使用在CH3OH/H2O（10：90％，v/v）。在这些条件下记录高度灵敏(230nM检测极限)和精确(RSD<4.0%)的测量。结果还表明，AZM随着温度的升高而降低其半衰期，暴露于紫外线辐射的时间，和空气饱和度增加。这一事实加强了对基于AZM的药物的连续质量控制的需求，使用更接近运输和储存过程中观察到的条件，减少对消费者健康的影响。
