基于乙烯基砜表面构建双向密度梯度的通用策略及其在生物检测芯片制备的研究

Versatile Bidirectional Density Gradients Constructing Strategy Based on Vinyl Sulfone Surfaces for the Study of Bio-detection Chip Preparation

报道了一种基于乙烯基砜(VS)表面的双向密度梯度构建的新策略,该策略能够在生物配体梯度表面上直接生长惰性聚合物刷而不需要额外的表面改性.采用该策略制备明确的配体密度芯片可用于在复杂生物流体中对应抗体的高特异性检测.选择荧光素作为小分子活性配体模型以发展和验证该策略.采用该策略制备荧光素和两性离子聚合物刷组成的双向密度梯度样品,并通过荧光素抗体(anti-FITC)在样品表面的皮尔森系数优选出聚甲基丙烯酸磺基甜菜碱(PSBMA)作为惰性配体.该双向密度梯度样品对anti-FITC和牛血清白蛋白(BSA)分别具有良好的特异性和抗非特异性结合能力.通过该策略制备了具有明确anti-FITC吸附性能的荧光素芯片,发现高密度荧光素芯片在BSA和50%胎牛血清(FBS)溶液中对anti-FITC具有高的特异性和敏感性.此外,选择抗人绒毛膜促性腺激素抗体(anti-HCG)和抗β2-微球蛋白抗体(anti-BMG)作为生物大分子模型验证该策略的通用性.因此,该策略不仅可以作为双向密度梯度制备的通用方法,而且可为生物检测芯片的制备提供理论指导.

A new strategy of constructing the bidirectional density gradients based on vinyl sulfone(VS)surfaces was developed,which could promote the direct growth of the polymer brushes on the bioactive ligand density gradient surface without any modifications.The chips with well-defined densities of the ligands prepared using such strategy can be used for specific detection of corresponding antibody in complex biological fluids.Fluorescein was selected as the small biomolecule model to develop and demonstrate this strategy.Bidirectional density gradient samples composed of fluorescein and zwitterionic polymer brushes were prepared,and poly(sulfobetaine methacrylate)(PSBMA)was selected as preferable inert ligand by evaluation of the Pearson coefficient of fluorescein antibody(anti-FITC)on the sample surface.The samples showed excellent specific and anti-nonspecific binding towards anti-FITC and bovine serum albumin(BSA),respectively.The fluorescein chips with well-defined adsorption property of anti-FITC were prepared by this strategy.And we demonstrated the chip with high fluorescein density in BSA and 50%fetal bovine serum(FBS)solution displayed high specificity and sensitivity towards anti-FITC.In addition,the universality of the strategy was evaluated using human chorionic gonadotropin antibody(anti-HCG)and beta-2-microglobulin antibody(anti-BMG)as biomacromolecule models.Overall,such strategy can not only act as universal method for preparing bidirectional gradient samples,but also provide theoretical guidance for the preparation of bio-detection chips.