【摘要】 利用双偏振极化干涉（Dual polarization interferometry,DPI）测量技术实时研究了三磷酸腺苷（ATP）与其适配体（ATP-binding aptamer,ABA）间的相互作用。将单链ABA固定在DPI氮化硅芯片上,采用DPI技术实时监测ATP与固定的ABA的相互作用过程中敏感层的质量、厚度、密度的变化。通过详细分析敏感层质量变化,得到ATP与ABA间的结合速率常数(k_a=4.66×10³L/（mol·s）、解离速率常数(k_d=1.70×10^-2·s^-1)、结合常数（K_A=2.7×10⁵L/mol）和解离常数(KD=3.7×10^-6mol/L)。通过测定敏感层质量、厚度和密度随ATP浓度的变化,分别建立了测定ATP的方法,检出限（LOD,3σ）分别为0.22μmol/L（质量变化）、0.14μmol/L（厚度变化）、0.32μmol/L（密度变化）。本研究利用DPI技术揭示了ABA与ATP相互作用中结构变化的实时信息,构建了新型ATP传感器,用于实际血清样品中ATP的检测,结果令人满意。更多还原

【Abstract】 In this work,we used dual-polarization interferometry to explore the binding events between adenosine triphosphate（ ATP） and ATP-binding aptamer（ ABA） at solid-liquid interface. The single-stranded ABA was immobilized onto the chip surface. After the addition of ATP,the real-time and label-free technique for detailed investigation of their interactions were reflected on the changes of the mass,thickness,and density through DPI. By analysis of the binding curves from changes in mass,the association rate constant( k_a,4.66×10³L/（ mol·s）,dissociation rate constant( k_d,1.70 × 10^-2s^-1),dissociation constant（ KA,2.7 ×10⁵L/mol）,and association constant( KD,3.7 × 10^-6mol/L) were precisely determined. Moreover,good linear correlations between ATP concentrations and three parameters（ mass,thickness,density） resolved by the response to ATP binding were obtained. The detection limits（ LOD,3σ） were 0. 22 μmol/L for mass calibration,0.14 μmol/L for thickness calibration,and 0.32 μmol/L for density calibration. We expect that this DPI-based aptasensor can be utilized to study the interactions of functional ABA with ATP,and also can be used for the detection of ATP with high sensitivity.更多还原