Study On The Toxicity Of Three Nanometer Energetic Materials

The development of nano-scale energetic materials has brought tremendous changes to the military industry.It not only has higher melting point,lower vapor pressure,excellent thermal stability and detonation stability,but also has the advantages of being insensitive to low-pressure long pulse stimulation and sensitive to high-pressure short pulse stimulation.In addition,its impact on the environment and humans has also attracted widespread attention.In recent years,studies on the toxicity of nanomaterials have mostly focused on the toxicity of materials such as metals,metal oxides,carbon nanomaterials,and quantum dots,while there have been few reports on the toxicity of nano-energetic materials,especially on nano-scale energetic materials.Research and evaluation of animal cell and microorganism toxicity.This paper studies the cellular and bacterial toxicity and toxicity mechanism of the three typical nano-sacle energetic materials,namely hexanitrostilbene（HNS）,triaminotrinitrobenzene（TATB）and 2,6-diamino-3,5-dinitropyrazine-1-Oxidation（LLM-105）.Researched separately:（1）The mouse macrophage RAW264.7 cells and the mouse fibroblast L929 cells were used as the model cells for the poisoning experiment.The cell activity was detected by CCK-8 colorimetric method,and the morphological changes of the cells were observed under the microscope.The activities of dehydrogenase（LDH）,peroxide dismutase（SOD）,malondialdehyde（MDA）content and apoptosis level were measured to analyze and judge the mechanism of cell death.（2）Taking Escherichia coli and Bacillus subtilis as model bacteria,the optical density method was used to detect the survival rate of bacteria,and the effects of particle size,dispersion medium,and type of bacteria on their toxicity were investigated.The mechanism of bacterial death was analyzed and analyzed by observing the morphological changes of bacteria,the hydrophobicity of the bacterial surface,and the sedimentation characteristics of bacteria-nanoparticles.The research results are as follows:（1）Nano-scale energetic materials HNS,TATB,LLM-105 can cause a significant decrease in the activity of RAW264.7 cells,and show a dose-dependent.Among them,the half inhibitory concentration(IC₅₀)of HNS,TATB and LLM-105 on RAW264.7 cells were 49.3,211.3 and 6.6μg·m L^-1,respectively.With the increase of the dose,the cell morphology changed,and the activity of LDH enzyme in the supernatant also showed an upward trend,indicating that the integrity of the cell was damaged.Among them,the change of oxidative stress index in HNS-infected cells is not obvious;TATB can cause the decrease of intracellular SOD activity,but the content of MDA does not increase significantly;and the activity of SOD enzyme in LLM-105 infected cells decreases,and the content of MDA increases.At the same time,the three materials can induce increased levels of apoptosis in mouse macrophages.This shows that HNS induces apoptosis,and the middle and late stages of apoptosis can destroy the structural integrity of the cell and reduce cell activity;TATB can cause the decrease of intracellular SOD activity and trigger oxidative stress,but it does not cause serious Oxidative damage also induces cell apoptosis,resulting in a decrease in cell viability;LLM-105 causes oxidative stress in the cell,causing oxidative damage to the tissue,inducing cell apoptosis,which in turn leads to a decrease in cell viability.（2）Nano-scale energetic materials HNS,TATB,LLM-105 have toxic effects on L929cells,LLM-105 has the strongest toxic effects on L929 cells,followed by HNS,and TATB has weak toxicity.With the increase of the dose,the cell morphology changed,and the activity of LDH enzyme in the supernatant also showed an upward trend,indicating that the integrity of the cell was damaged.In addition,there was no significant change in the oxidative stress indexes in HNS and TATB-infected cells,and the effect on apoptosis was weak;the LMD-105-infected cells had decreased SOD activity and increased MDA content,and induced apoptosis.This shows that destroying the integrity of the cell membrane is an important cause of cell death caused by HNS and TATB;and LLM-105 can cause apoptosis by generating internal oxidative stress,which in turn leads to cell rupture,bad maggots,and decreased cell viability.For different nanomaterials,their biological toxicity effects and mechanisms are different.Even if they are the same type of material,the test subjects are different,and the toxicity mechanism is also different.（3）Among the nano-level energetic materials HNS,TATB,and LLM-105,only LLM-105 has obvious toxicity to bacteria,so the microbial toxicity effect of LLM-105 is mainly studied.Using LB medium as the dispersion medium,the toxic effects of nano-and micro-scale LLM-105 on E.coli were compared.It was found that the particles of both particle sizes had a toxic effect on E.coli,showing a size-effect relationship.The toxicity of nano-sized particles was significantly stronger than that of micro-sized particles;LLM-105 was more toxic in LB medium than in MD medium It showed stronger bacterial toxicity;at the same time,it was also found that LLM-105 is more toxic to E.coli than Bacillus subtilis.Finally,from the scanning electron microscopy of bacteria,the hydrophobicity and sedimentation characteristics of the cell surface,it can be seen that LLM-105 can contact the bacterial surface and cause the bacterial morphology and structure to change,resulting in bacterial cell rupture and death.