School of Pharmacy, Bandung Institute of Technology, Bandung 40132, Indonesia.
Department of Chemistry, School of Science, Tokyo Institute of Technology, Tokyo 152-8551, Japan.
Molecules. 2022 Mar 27;27(7):2166. doi: 10.3390/molecules27072166.
This research dealt with the composition, structure determination, stability, and antibiotic potency of a novel organic salt composed of levofloxacin (LF) and citric acid (CA), named levofloxacin-citrate (LC). After a stoichiometric proportion screening, the antibiotic-antioxidant reaction was conducted by slow and fast evaporation methods. A series of characterizations using thermal analysis, powder X-ray diffractometry, vibrational spectroscopy, and nuclear magnetic resonance confirmed LC formation. The new organic salt showed a distinct thermogram and diffractogram. Next, Fourier transform infrared indicated the change in -methylamine and carboxylic stretching, confirmed by H nuclear magnetic resonance spectra to elucidate the 2D structure. Finally, single-crystal diffractometry determined LC as a new salt structure three-dimensionally. The attributive improvements were demonstrated on the stability toward the humidity and lighting of LC compared to LF alone. Moreover, the antibiotic potency of LF against (Gram-positive) and (Gram-negative) enhanced ~1.5-2-fold by LC. Hereafter, LC is a potential salt antibiotic-antioxidant combination for dosage formulas development.
本研究涉及一种由左氧氟沙星（LF）和柠檬酸（CA）组成的新型有机盐左氧氟沙星柠檬酸盐（LC）的组成、结构确定、稳定性和抗生素效力。经过化学计量比例筛选，采用缓慢和快速蒸发法进行抗生素-抗氧化剂反应。一系列使用热分析、粉末 X 射线衍射、振动光谱和核磁共振的特征分析证实了 LC 的形成。新的有机盐表现出明显的热图谱和衍射图谱。接下来，傅里叶变换红外光谱表明 -甲基胺和羧酸伸缩的变化，通过 H 核磁共振谱证实，阐明了二维结构。最后，单晶衍射法确定 LC 是一种新的三维盐结构。与单独的 LF 相比，LC 在湿度和光照下的稳定性得到了显著改善。此外，LC 使 LF 对 （革兰氏阳性）和 （革兰氏阴性）的抗生素效力提高了约 1.5-2 倍。因此，LC 是一种有潜力的盐类抗生素-抗氧化剂组合，可用于开发剂量配方。
