The Study On Preparation And Pharmacodynamics Of DDTC And EDTA Atomization Inhalation Freeze-Dried Powder

OBJECTIVE: This study referred to the sodium diethyldithiocarbamate(DDTC)with Ethylenediaminetetraacetic acid(EDTA)drug combinations in the treatment or prevention of infection.Bacterial growth and reproduction are inseparable from metal ions,and EDTA and DDTC are metal ion chelators.The purpose of this project is to develop antibiotic sensitizers for the treatment of severe pulmonary drug-resistant infections.After a large number of screening tests in the early stage,DDTC mainly acts as a Zn2+ inhibitor,while EDTA mainly chelate Mg2+,Ca2+,Fe2+,etc.EDTA and DDTC have significant synergistic effects as antibacterial sensitizers.It was prepared into freeze-dried powder atomization inhalation.The quality of preparation was examined.On this basis,the in vivo antibacterial effect of the combination preparation was further examined by animal experiments.The purpose of this study was to provide a new idea for the clinical treatment of severe pulmonary drug-resistant infections.METHOD:(1)Based on the combined use of antibiotics,the antibacterial effects of EDTA and DDTC on drug-resistant bacteria were investigated by microdilution method by selecting drug-resistant bacteria with higher resistance in the test strains.Determine the synergistic effect of increasing bacterial sensitivity by using the microdilution method and determine the appropriate proportion.(2)Preparation of freeze-dried powder atomization inhalation preparation: According to the physical and chemical properties of the main drug,establish an in vitro HPLC method.Development of freeze-dried powder atomization inhalation with atomization performance and stability as indicators.The quality of the preparation was investigated.(3)The toxicity test of the combination was examined.(4)Verification of in vitro antibacterial activity of EDTA and DDTC combinations atomization inhalation freeze-dried powder.(5)Determination of the efficacy of the drug in vivo: Mice were infected with Klebsiella pneumoniae to model.Model group mice were treated with a combination of aerosol inhalation and antibiotic injection.To observe the effect of aerosolized EDTA and DDTA combinations on the therapeutic effect of antibiotics on Klebsiella pneumoniae infection pneumonia.RESULTS:(1)Through the investigation of the antibacterial effects of three pan-resistant bacteria,the combination of DDTC and EDTA could restore the sensitivity of pan-drug resistant bacteria to antibiotics.It could reduce the MIC value of antibiotics such as meropenem,cefoperazone sulbactam and amikacin.DDTC and EDTA had a significant synergistic effect in increasing bacterial sensitivity.The efficiency of 44 strains of different resistant bacteria was above 90%.(2)A HPLC analytical method was established.The content of the preparation was determined,the prescription screening and the process research were carried out,and an atomization inhalation freeze-dried powder with stable quality and good appearance was prepared.The lyophilized powder was dissolved in water for injection to obtain an atomized solution.The resolubility and appearance were all in accordance with the requirements,and the measured particle diameter Dv(50)was 4.42 ?m.(3)Through acute toxicity test of inhalant and electrocardiogram test of Beagle dog,it was concluded that high-concentration combination aerosol inhalation had no serious respiratory toxicity in mice,and there was no obvious change in lung structure.Intra-abdominal injection was performed in dogs.There were no statistical differences in ECG indicators before and after administration,suggesting that there might be no toxic effects on the heart after administration.The cell proliferation toxicity test suggested that the combination might not be significantly toxic.(4)The in vitro antibacterial effect of the combination preparation obtained by the prescription research and the process inspection was comparable to that of the previous antibacterial effect.(5)In the mice pneumonia model,the combined treatment of aerosolized combination and antibiotics was used.Compared with the model group,the mice in the combined treatment group had significantly reduced lung bacterial count and lung inflammation,which significantly improved the therapeutic effect of antibiotics.CONCLUSIONS: The DDTC and EDTA combinations could restore the sensitivity of pan-drug resistant bacteria to antibiotics,and the atomization inhalation freeze-dried powder had good stability and appearance,and was favorable for preservation and transportation.The atomized inhalation solution obtained by dissolving the atomization inhalation lyophilized powder was examined for the particle size of the water mist,which was in accordance with the particle size requirement of the pulmonary inhalation preparation.Through the in vivo pharmacodynamic study of mice,a certain therapeutic effect was obtained,and the combination prepared in this study had certain research significance,which provided a theoretical basis for further research in the future.