Preparation And Pharmacodynamics Study On Compound Florfenicol Solution

Purpose:My test made the solution of florfenicol and doxycycline in a 1:2 ratio, determine the amount of auxiliary material by orthogonal experiment, and study the solution by doing the impact factors test, in vitro antimicrobial test, combined sensitivity test and acute toxicity test to provide information and evidence for further study of it.Methods:1.Optimization of prescription:In accordance with Veterinary Pharmacopoeia of People’s Republic of China I constructed the analysis to drug content by HPLC, and then through the pre-trial selected 4 auxiliary materials as the orthogonal experiment factors, each factor choose three levels and designed the L9(34) orthogonal experiment, according to the design prepared relevant samples and measured the content change of the samples between 20 days at 40℃ constant temperature environment, by using orthogonal assistant to analysis, I finally own a reasonable proportion of auxiliary materials;2.Stability trial:I constructed the analysis to drug content by UV spectrophotometry, and based on ChP, selected three environmental factors which are high temperature(60±2℃), high humidity(90±5%) and bright light(4500±500lx), set the solution at them with 10 days, observed changes of color and clarity and measured the drug content at 0d, 5d and 10 d,to which study the impact of three environmental factors on the solution;3.Antibacterial and combined sensitivity trial:Using broth dilution method and plate culture to determine the MIC and MBC of two drugs by escherichia coli, salmonella, staphylococcus aureus, pasteurella and agalactiae, measuring the combined effects of two drugs to use tube board dilution method by five kinds of bacteria, and obtaining results by the corresponding FIC value based on the criteria;4.Acute toxicity trial:In accordance with the two-step to perform the pre-trials, finding out the dose range of 0 and 100% mortality by doxycycline content, and with reference to Dn and Dm setting the dose ratio between groups r. Formal test is divided into six experimental groups, according to the r to thin drugs, the oral dosing volume chooses 0.8mL, observing the number of deaths in 7d and calculating the LD50 and 95% confidence intervals(FL) by using the modified Karber’s method.Results:1.Optimization of prescription:The amount of auxiliary materials is determined as follows:water 10mL/100 mL, NN-dimethylformamide 2.5mL/100 mL, magnesium chloride 6g/100 mL. Accordingly I obtain the following formula:per 100 mL preparations containing florfenicol 5g, doxycycline 10 g, water 10 mL, polyethylene glycol-400 30 mL, NN-dimethylformamide 2.5mL, magnesium 6g, sodium pyrosulfite 0.2g and using propylene glycol to fill the remaining volume;2.Stability trial:Results show that the high temperature condition had the highest degree of influence, content variations were 0.50% and 4.42%; the bright light condition existed the influence, content variations were 0.97% and 2.33%; the high humidity condition had almost no influence, content variations were 0.18% and 0.31%;3.Antibacterial and combined sensitivity trial:Results show that the MIC are in 8~32 μg/mL, inhibitory effect is good, the MBC are more than 128μg/mL except pasteurella, sterilization effect is poor. the combined results show that escherichia coli is the unrelated effect, salmonella, staphylococcus aureus and agalactiae are the additive effect, and pasteurella is the synergistic effect;4.Acute toxicity trial: Through a pre-trial I obtained 100% lethal dose(Dn) is 4000mg/Kg and 0% lethal dose(Dm) is 2000mg/Kg, dose ratio between groups(r) is 1:0.85, according to the mortality rate obtained the LD50 is 2579.24mg/kg, 95% confidence limit is 2274.32~2925.03mg/kg.Conclusion:Established the HPLC and UV method of drug content detection; determined auxiliary materials reasonable amount of compound florfenicol solution by orthogonal experiment;the stability test shows that the solution is sensitive to temperature and light, so we should pay attention in production and storage;by measuring the MIC, MBC and FIC values of florfenicol and doxycycline to escherichia coli, salmonella, staphylococcus aureus, pasteurella and agalactiae and I own some results:inhibitory effects of both drugs for five kinds of bacteria are very good, but killing effects are poor, and the result of two-drug combination has significantly positive effect, so they can be used in combination;according to the acute toxicity test the LD50 of the solution is 2579.24mg/kg, 95% confidence limit is 2274.32 ~ 2925.03 mg / kg, which is low toxicity drugs, but its higher viscosity and poor palatability should be pay attention.