表面等离子体共振成像法用于糖蛋白分析

Glycoproteins Analysis by Surface Plasmon Resonance Absorption and Imaging

建立了一套表面等离子体共振成像方法,用于筛选糖蛋白和非糖蛋白,并可以区分不同糖蛋白与伴刀豆凝集素的识别强度.波长调制的表面等离子体共振与成像法所得结果一致.伴刀豆凝集素的洗脱成像实验为识别强度提供了补充验证方案.

Surface plasmon resonance （SPR） absorption and imaging（SPRI） have been explored for screening and differentiating glycoproteins from non-glycoprotein according to the shift of maximum SPR absorption and/ or to the variation of picture gray intensity. In combination with competitive washing with sugar solutions, SPRI has the ability to produce different signals for different gylcoproteins, offering a potential way to identify these gylcoconjugates. To conduct SPR and SPRI, proteins（at 1.0 mg/mL）, in stead of lectins, were immo- bilized on gold sensing films to reduce the use of the costly glyeoproteins. The sensing film was fixed in a labo- ratory-established SPR or SPRI system, equilibrated with 50 mmoL/L Tris-HCl at pH = 7.4 at a flow rate of 20 μL/min, reacted with 200 nmol/L ConA（ prepared in the Tris-HC1 solution containing 120 mmol/L NaCl, 25 mmol/L CaCI2 and 5 mmol/L MnCl2 ） at room temperature for 1 h and rewashed with Tris-HCl solution. For competitive washing, 80 mmoL/L glucose solution was pumped into the analytical cell and reacted for 1 h. The signals were recorded whenever necessary. Non-gylcoproteins had no signals when using either SPR or SPRI while glycoproteins gave different SPR shifts and gray intensity in SPRI.