Toxic Effects Of Ofloxacin And Copper And Their Complexing Systems On African Green Monkey Kidney Cells (Vero)

The abuse of antibiotics have attracted a great deal of health concern.Heavy metal ion universally exists in soil and water environment.Its strong elusive peculiarity ensures that the heavy metal could easily give rise to the poisoning of flora and fauna through food chain.And the combination of antibiotics and heavy metal ions makes their environmental risk assessments more complex.To study the complex pollution of the antibiotic and heavy metal iron to environment is significant.This research chooses the typical object in antibiotics—Ofloxacin?OFL?,and the popular researching subject in heavy metal—Cu²⁺,to be the experimental subjects.A combined pollution experiment would be conducted to the Vero under the in-vitro cell culture,which would be used to the further analysis of the toxicity effect of OFL,Cu²⁺ and their clathrate to the Vero.Through the comparison of the toxicity effects of OFL and Cu²⁺ to the sigle and combined pollution of Vero,the essay would further discuss not only the influential factors?the temperature of pH?of the clathrate of OFL and Cu²⁺,but also the toxicity effect of the combined clathrate system.This research is of great value to the theoretical and practical analysis of the high risk of environment caused by the combined pollution of antibiotics and heavy metal.The results showed that:?1?OFL,Cu²⁺ and their clathrate would lead to the morphologic changes of cells,cell disruption and the decrease of anchorage-dependent ratio.With the increase of the concentration of Cu²⁺ from 6.88 mg-L-1 to 6875 mg-L-1,its inhibition ratio to Vero also increases 55%.OFL has great influence on the growth of Vero.OFL will stimulate the growth of Vero if its concentration is under 3 mg-L-1.Otherwise,it will begin to inhibit the growth of Vero.?2?When the concentration is 2.75 mg-L-1 Cu²⁺,the concentration of OFL increases from 0.63 mg-L-1 to 10 mg-L-1,while the inhibition ratio of its combined contaminant to cells increases from 24%to the highest 47%.When the concentration of OFL is 2.5 mg-L-1,5 mg-L-1 and 10 mg-L-1,the cells' inhibition ratio of the complex of OFL and 2.75 mg-L-1 Cu²⁺ is greatly different with the sum of single inhibition ratios of OFL and Cu²⁺.The inhibition ratio of the complex shows the trend of decrease.At the same time,the similar phenomenon happens when Cu²⁺concentration is under 6.88 mg·L-1.The cells' inhibition ratio of the complex of OFL and 6.88 mg-L'1 Cu²⁺ is greatly lower than the sum of single inhibition ratios of OFL and Cu²⁺.In conclude,the toxicity of the complex of OFL and Cu²⁺is lower than the sum of their single polluting toxicities.?3?In the DMEM cell culture medium,the quantity of free OFL and Cu²⁺ is apparently lower than the quantity in the water environment.This data indicates that OFL and Cu²⁺ would react with other materials in the DMEM cell culture medium,which would form a combined clathrate system mainly based on OFL and Cu²⁺.?4?Temperature and pH value changes would greatly influent on the total concentration of OFL-Cu²⁺ combined clathrate system in the DMEM cell culture medium.With the increase of temperature,the total concentration of OFL-Cu²⁺combined clathrate system also increases,which means that temperature influences not only the activity of reaction between OFL and Cu²⁺ but also the reacting activity between both of them with the other subjects in the DMEM cell culture medium.With the increase of pH value,the total concentration of OFL-Cu²⁺ combined clathrate system also increases,which means that pH value of the environment directly influences on the reacting activity and clathrate ability between OFL and Cu²⁺.?5?OFL-Cu²⁺ combined clathrate system would not have toxicity effect on the growth of Vero cell.This shows that compared with the sum of single polluting toxicity of OFL and Cu²⁺,the main reason of the relatively decrease of combined polluting toxicity of OFL and Cu²⁺ is that in the combined polluting system the DMEM cell culture fluid would react with OFL and Cu²⁺,which would give rise to the generation of the OFL-Cu²⁺ combined clathrate system.This system would not effect on the growth of Vero cell,thus it reduces the total toxicity of the combined pollution of OFL and Cu²⁺.Therefore,the combined toxicity of the antibiotic OFL and the heavy metal Cu²⁺to Vero cell would decrease with the appearance of OFL-Cu²⁺ combined clathrate system,indicating that OFL and Cu²⁺ has an antagonistic effect on the toxicity effect of the growth of OFL and Cu²⁺.It shows that the potential antagonism between pollutants in the environment can reduce the risk of the combined pollution to the environment.