Synthesis And Characterization Of Cucurbit [6] Urilbased Supramolecular Complex Based And Its Application In Antibiotic Detection

Cucurbit[n]uril(CB[n]s)molecule has attracted widespread attention due to its special structure and properties in recent years.The more polar carbonyl oxygen atoms at the two ports of CB[n]s can coordinate with metal ions,its surrounding hydrogen atoms and oxygen atoms.can produce hydrogen bonding force,C-H...?interaction force?...?and other weak interactions with some organic ligands,and then it construct supramolecular complexes with novel structure and excellent performance.As a new material,supramolecular complexes have attracted much attention in the analysis and detection of environmental pollutants.The excessive use or abuse of antibiotics in livestock and poultry breeding has caused serious ecological and environmental problems and endangered human health.Most of the traditional antibiotic detection methods have disadvantages such as expensive equipment,cumbersome operation,time-consuming detection and so on,which are difficult to adapt to the development needs of antibiotic detection.In this paper,using CB[6]as a research platform,screening a series of fused-ring aromatic compounds as structure inducers,successfully constructed two new supramolecular complexes based on CB[6],and passed single crystal X-ray diffraction,powder X-Ray diffraction and other methods are used to characterize the structure and use it as a fluorescent probe to detect some commonly used antibiotics,establishing a new method for rapid and sensitive antibiotic detection.At the same time,we analyzed the detection mechanism.The specific work is as follows:1.Using the aromatic compound 4,4'-biphenyldisulfonic acid(H₂BPDS)as the structure directing agent and Na⁺as the central ion,a novel CB[6]-based supramolecular assembly[Na₄CB[6](H₂O)₁₀DMF]·2BPDS·2H₂O(1)was successfully synthesized.Structural analysis shows that each CB[6]molecular port is coordinated with two Na⁺ions to form[CB[6]-Na₄]⁴⁺cations.[CB[6]-Na₄]⁴⁺and BPDS^2-pass through non-common Valence interaction combination.Fluorescence analysis shows that complex 1 can be used as a fluorescent probe to achieve sensitive and rapid detection of two commonly used fluoroquinolone antibiotics,levofloxacin(LUX)and gatifloxacin(GAT).At the same time,it is used for the detection of GAT in simulated wastewater and artificial urine with good recovery.2.Using 9-anthracenecarboxylic acid(HL)as the structure directing agent and Cd²⁺as the central ion,a new type of superpartition compound[Cd L₄]^2-·CB[6](2)based on CB[6]was synthesized.The structure analysis showed that the Cd²⁺ion is coordinated with the carboxyl oxygen atoms of four HL molecules to form isolated pinwheel-like[Cd L₄]^2-complex anion.The CB[6]molecule and[Cd L₄]^2-pass non-covalently.The interaction and combination form a three-dimensional supramolecular complex 2.Performance studies have shown that 2 can be used as a fluorescent probe to detect the furan antibiotics nitrofurazone(NFZ)and nitrofurantoin(NFT),and show extremely high selectivity and sensitivity;Complex 2 showed a good recovery rate for antibiotics in simulated wastewater and artificial urine.The complex 2 was successfully prepared into a strip to realize the simple,rapid and visual detection of NFZ/NFT.