Molecular interactions between the main components of Shuanghuanglian injection and ciprofloxacin injection based on self-assembly / 药学学报

The combination of Shuanghuanglian injection (SHLI) and ciprofloxacin injection (CIPI) is frequently prescribed in clinical practice, but the basis for the combination is weak. In this study, isothermal titration calorimetry and ultraviolet-visible absorption spectrometry were applied to identify the molecular interactions of SHLI and its main components, chlorogenic acid and neochlorogenic acid with CIPI. Scanning electron microscopy, Fourier-transform infrared spectroscopy, and cold-spray ionization mass spectrometry were performed to confirm that this molecular interaction was related to the formation of self-assembled supramolecular systems induced by chlorogenic acid and neochlorogenic acid with CIPI through weak intermolecular bonds. The antibacterial activity toward Pseudomonas aeruginosa (P. aeruginosa) was evaluated via molecular interactions, and the inhibitory ability of SHLI, chlorogenic acid and neochlorogenic acid against P. aeruginosa was significantly reduced after interaction with CIPI. A molecular docking study demonstrated that the reduced antibacterial ability was closely related to the competitive binding of drug molecules to the same binding site of the DNA gyrase B (GyrB) subunit of P. aeruginosa. The present study uncovered the intermolecular interactions of SHLI and its main components chlorogenic acid and neochlorogenic acid with CIPI from the perspective of molecular self-assembly and contribute to the reduction of its antibacterial ability, providing a basis for the clinical combination of SHLI and CIPI.

Determination of the Contents of Components in Co-ciprofloxacin Injection by RP-HPLC / 中国药房

OBJECTIVE:To determine the contents of ciprofloxacin and tinidazole in compound ciprofloxacin injection.MET_HODS:RP-HPLC method has been developed.The moble phase was 0.4mol/L citric acid-methanol-acetonitrile(2∶1∶0.8).The flow rate was 0.8ml/min.The detective wavelength was 277nm.RESULTS:The average recovery and relative stan_dard deviation were 99.7% and 0.9% for ciprofloxacin,99.6% and 0.7% for tinidazole.CONCLUSION:This method is rapid,simple,accurate and suitable for the quality control of this preparation.