Antibacterial Imaging And Bacterial Detection Of Imidazolium-typc(Poly) Ionic Liquids

Bacterial infections can damage host cells and tissues.threatening human life safety and health.Especially the emergence of drug-resistant bacteria and the increasing resistance have further exacerbated the harm of bacterial infections.Research on high-efficiency,broad-spectrum and non-resistant antibacterial materials is also a major challenge to eliminate bacterial infections.Ionic liquids are organic molten salts composed of anions and cations.Poly(ionic liquid)s are polymers containing ionic liquids in the structure and possess the properties of both ionic liquids and polymers.In recent years,poly(ionic liquid)s have received widespread attention in the field of antibacteria.The electrostatic interaction between cations and electronegative bacterial cell membranes and the hydrophobic interaction between the hydrophobic segment and phospholipid bilayer can effectively kill bacteria.Utilizing the structural designability of poly(ionic liquid)s,it is possible to prepare multifunctional antibacterial materials.This paper focuses on imidazolium-type ionic liquids,designs and synthesizes a series of multifunctional antibacterial ionic liquid small molecules and polymers Systematically research the application of imidazolium-type ionic liquids in antibacterial,bacterial imaging and detection,and further study the influence of different antibacterial materials on the formation of bacteria information communication channel--the nanotubes.The main research contents and conclusions of this paper are as follows(1)Design and synthesis of imidazolium-type ionic liquids with aggregation-induced fluorescence TPE-CnIm(n=1、4、8),and study the application in antibacterial and bacterial imaging and detection.A series of aggregation-induced emission-based ionic liquids(AIE-ILs)with different alkyl chain lengths of substituents at the N3 position were synthesized.The effects of alkyl chain length on the fluorescence intensity.antibacterial properties.and biocompatibility of AIE-ILs were systematically studied and applied to the fluorescence imaging and detection of bacteria in blood.Studies have shown that AIE-ILs can kill almost 99%of bacteria and have good biocompatibility,and these properties are affected by the length of alkyl chain at the N3 position.In addition,AIE-ILs can achieve fluorescence imaging of dead bacteria at the macro and micro levels while sterilizing.As for bacteria in blood cells,AIE-ILs can also kill and detect bacteria,which make these new ILs as new fluorescence sensor candidates to detect pathogenic bacteria in blood cells.(2)Design and synthesis of imidazolium-type ionic liquid homopolymers and copolymer membranes.The effect of the synthesized poly(ionic liquid)s on bacterial nanotubes formation was studied.A series of imidazolium-type ionic liquid homopolymers and copolymer membranes with different imidazolium content(20%,30%and 50%)(PILn,n=20、30、50)were synthesized.The effects of imidazolium-type antibacterial poly(ionic liquid)s on nanotubes were systematically studied by observing the number and morphology of nanotubes between homologous and heterologous bacteria.The effect of antibacterial activity and coculture time on the formation of nanotubes was first studied.And different systems,including homogeneous phase(solution)and different phases(solution/solid)were further studied.The results show that poly(ionic liquid)s can significantly promote the formation of nanotubes;and the antibacterial activity differences of the copolymer membranes can induce different forms and numbers of nanotubes,including protrusions(ENs)and intercellular connected nanotubes(ICNs).At the initial stage of contact between bacteria and PILn,the amount of ENs on PIL30 membranes are the largest,about 1.6 times that of PIL20 membranes and 3.5 times that of PIL50 membranes;which PIL50 membranes have the highest proportion of ICNs,which is about twice as much as PIL30 membranes.Moreover,bacteria co-cultured with ionic liquid homopolymers tend to form very short nanotubes,which are different from the morphology of the nanotubes formed on the copolymer membranes.