Preparation Of Lanthanide Fluorescent Coordination Materials And Study On Their Biosensing Properties

Due to various structures and excellent optical properties,lanthanide fluorescent coordination materials have always been favored by many researchers.This kind of material is widely used in materials science,biomedicine and other fields.The ligands with"antenna effect" in lanthanide complexes absorb ultraviolet light and transmit to the central ion,which then emits a characteristic spectrum.The characteristic spectrum emitted by the lanthanide complex is easily disturbed by the external environment,which makes the fluorescence increase,weaken or quench.Based on this problem,we synthesized two erbium coordination materials,studied the luminescence properties of the materials.At the same time,nano-sensing systems based on materials are used to detect proteins and small molecules with high sensitivity and specificity.The specific contents are as follows:(1)Preparation and characterization of MSN-Tb fluorescent confined nanostructures:By adjusting the solvent composition of the solvent,we obtained mesoporous silicon nanoparticles(MSNs)with good dispersion.The complexes Phen-Si and 1,3-diphenyl-1,3-propanedione were used to load Tb3+on the mesoporous silica to obtain MSN-Tb.A series of characterizations have confirmed the successful synthesis of MSN-Tb.At the same time,many characterizations have proved the superiority of MSN-Tb in terms of luminous intensity and light stability.Obviously,compared with free Tb3+confined by mesoporous silica showed enhanced fluorescence intensity and improved light stability.The experimental research can be used to optimize the lanthanide luminescent materials,and then the materials can be better used for sensing detection in various disciplines and fields(2)Based on the FRET mechanism,we realized the modification of MSN-Tb and applied it to the detection of deubiquitinaseBased on the resonance energy transfer(FRET)mechanism,we modified MSN-Tb and constructed a ratio-type sensing device,MSN-Tb-UbR,to detect the deubiquitinating enzyme(UCH-L1)associated with many diseases.When the sensor MSN-Tb-UbR is excited by ultraviolet light,resonance energy transfer can occur between Tb3+ and rhodamine B,the emission of Tb3+is suppressed,and the system emits red fluorescence of rhodamine B.After the addition of UCH-L1,the peptide bond between MSN-Tb and Ub-Rs is broken,and the emission of the terbium complex is restored.Experiments have confirmed that the sensor MSN-Tb-UbR can detect UCH-L1 with high sensitivity and specificity.Furthermore,UCH-L1 was tested linearly using human serum albumin to simulate the biological environment.The detection limit is as low as 5 nM.Compared with traditional immunoblotting and mass spectrometry,this method is sensitive and convenient.And MSN-Tb-UbR nanosensor has the potential to diagnose DUB-related diseases such as cancer and neurological diseases(3)Construction of TDA-Tb nano-fluorescent probes and applied it to the detection of mekacetoneWe use 2'2-thiodiacetic acid(TDA)and Tb3+as raw materials to construct TDA-Tb coordination polymers by a simple hydrothermal method.Tests show that the nanomaterial exhibits characteristic emission peaks of Tb3+at 489,545,584,620 nm.The emission peak is caused by 5D4?7F6,5D4?77F5,5D4?77F4,5D4?7F3 transitions.Based on the good luminescence characteristics of TDA-Tbs and the fact that fluorescent coordination polymers reported in recent years can interact with small molecules to cause changes in fluorescent intensity.We used TDA-Tbs as sensors,screened eleven drug molecules,and used them for the quantitative detection of mecarbidone(MEC).Compared with traditional detection methods such as gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry,the method is simpler and more convenient to operate,and the materials are cheaper and easier to obtain.