Application Of Boronate-affinity Hollow Molecularly Imprinted Polymers In Biological Sample Analysis

Numerous cis-diol-containing compounds exits in organism,such as:nucleosides,catecholamines and glycoproteins.These biomolecules not only own significant life functions?information transfer,metabolism,growth-promoting,etc.?,but also are used as disease marker to monitor disease in clinical medicine.However,due to the complex biological sample matrices and the lower content of these compounds,the interference is serious when direct detection and the data are inaccurate.Borate groups are a kind of groups which can specifically recognize cis-diol molecules.Therefore,the novel adsorption materials modified by borate groups have been used to separate and detect the cis-diol-containing compounds from biological samples in the present paper.This paper mainly includes the following two parts:Firstly,boronate-affinity magnetic hollow molecularly imprinted polymers?B-MhMIPs?were prepared for selective separation of sialic acid?SA?in serums.In the experiment,the magnetic nanoscale adsorption materials with hollow structure were synthesized,which used MCM-48 microspheres as sacrificial support,SA as the template,3-aminophenylboronic acid?APBA?as the functional monomer and glycidilmethacrylate?GMA?as the co-monomer to chemisorb Fe₃O₄ nanoparticles.Furthermore,the hollow structure of B-MhMIPs made the material have more binding sites at both internal and external surfaces,which can facilitate the removal of template molecules from polymers and enhance the adsorption abilities towards SA.After optimizing,the adsorption pH was controlled at 4.0,and this was different from most cis-diol-containing compounds.Under the optimal conditions,the limit of detection for SA was 0.025 mg/mL.This method was applied to analyze serum samples with different spiked levels,and the recoveries of the SA were in the range of 70.9-106.2%.These results confirmed the superiority of the B-MhMIPs for selectivity of trace SA from complex matrices.Secondly,novel boronate-affinity hollow dummy template imprinted polymers?B-hDIPs?were proposed for highly selective detection of catecholamines?CAs??norepinephrine,epinephrine,and dopamine?in human urine samples.The B-hDIPs were prepared by catechol as the dummy template,4-carboxyphenylboronic acid?CPBA?as the boronate-affinity functional monomer,nano-TiO₂ as the sacrificial support.The nano-TiO₂ can be etched by hydrofluoric acid to form the hollow structure,where more binding sites located on the inner and outer surfaces can be utilized maximum.Under the optimal conditions,the limits of detection were in the range of0.015-0.047?g/mL.Moreover,this method was successfully applied in the determination of three CAs in human urine,with the recoveries range from 63.4%to106.2%.Thus,the method in this paper proved to be an accuracy and practical platform for detection of CAs in complex matrices.