Construction Of Molecularly Imprinted Sensor Based On Boronate Affinity And Application In Glycoprotein Detection

Glycoprotein widely exists in mammals and plays an important role in many biological processes of human beings,such as molecular recognition,immune response and enzymatic reaction.Since many glycoproteins are disease related biomarkers,it is of great significance to carry out research on sensitive analytical methods of glycoproteins for clinical diagnosis of many diseases,including diabetes,cardiovascular diseases and various types of cancer.Ovalbumin（OVA）is a typical glycoprotein,which is the main allergen in egg white and often causes allergy in people,especially infants.In this paper,OVA is used as a model to ingeniously combine boron affinity,molecular imprinting technology and signal amplification strategy to build a sandwich structure magnetic molecular imprinting sensing platform for glycoprotein detection.The signal amplification strategy and sensing method showed good sensitivity and selectivity for OVA detection,indicating that the molecular imprinted sensor has important reference value for clinical detection of other similar glycoproteins or biomarkers.1.Based on boronate affinity and signal amplification strategy,a novel sandwich structure magnetic molecularly imprinted electrochemical sensor was constructed and used to detect ovalbumin.Magnetic molecularly imprinted polymers（MIPs）and signal amplifiers with ovalbumin as template molecules were synthesized（Si O₂@Au@Ab）.The MIPs have good adsorption capacity for protein OVA,with the adsorption capacity of 81.92mg g^-1and the imprinting factor of 2.40.With the unique biomimetic recognition and good adsorption of MIPs and the amplification of signal probes,the GCE/MIP@SAA The electrochemical sensor can complete the accurate detection of OVA within 3 min,with a linear range of 10^-11～10^-4mg m L^-1,and a detection limit of 3.0 fg m L^-1.It has the characteristics of simple,fast,high sensitivity and high selectivity.Meanwhile,the GCE/MIP@SAA The sensor also showed good repeatability,stability and selectivity in practical application.The recovery rate of OVA detection in actual sample red wine was92.80%～108.68%,and the RSD was 0.48%～2.58%.It shows that the signal amplification strategy and sensing method have important reference value for clinical detection of other similar glycoproteins or biomarkers.2.A magnetic molecularly imprinted fluorescence sensor with sandwich structure was developed（MIP@OVA@TCPP-BA）method for detecting OVA.Firstly,the boron affinity magnetic ovalbumin imprinted nanomaterials were used to specifically bind ovalbumin,supplemented by boric acid modified tetra（4-carboxyphenyl）porphyrin nanoparticles（TCPP-BA）as probes,to form sandwich structures with TCPP-BA and OVA through the imprinted cavities in MIPs.Under alkaline conditions,TCPP-BA nanoparticles were destroyed to restore strong fluorescence（turn-on mode）,and the sensitive detection of ovalbumin was successfully realized.Built MIP@OVA@TCPP-BA,the fluorescence signal of sensor has a good linear relationship with OVA content in the concentration range of 10^-12～10^-6mg m L^-1（R²=0.9934）,and has a higher detection sensitivity,with a detection limit of 2.14 fg m L^-1（S/N=3）.