基于新型比色探针的分光光度法测定β-淀粉蛋白寡聚体的含量  

Determination ofβ-Amyloid Oligomer by Spectrophotometry Based on the Novel Colorimetric Probe

作　　者：周信光 于妍妍 ZHOU Xinguang;YU Yanyan(Shenzhen NTEK Testing Technology Co.,Ltd.,Shenzhen 518000,China;Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy,School of Pharmacy,Xuzhou Medical University,Xuzhou 221004,China)

机构地区：[1]深圳市北测检测技术有限公司,深圳518000 [2]徐州医科大学药学院,江苏省新药研究与临床药学重点实验室,徐州221004

出　　处：《理化检验（化学分册）》2022年第12期1365-1371,共7页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：国家自然科学基金项目(No.21675137);江苏省自然科学基金(No.BK20201457)。

摘　　要：基于制备的包载葡萄糖信号分子的聚乙烯亚胺(PEI)功能化介孔二氧化硅纳米粒子(PEI-MSN)以及mAPOE多肽标记的金纳米粒子(mAPOE-AuNPs),通过将竞争置换反应与比色分析技术联合,构建了一种能够对β-淀粉蛋白寡聚体(Aβo)高效检出的新型简单比色探针(PEI-MSN/mAPOE-AuNPs)。将负电荷的mAPOE-AuNPs静电吸附在正电荷PEI-MSN表面,然后将葡萄糖包载进入介孔二氧化硅纳米粒子(MSN)孔隙并封堵。当Aβo存在此体系时,由于Aβo与mAPOE多肽之间的特异性作用力大于mAPOE-AuNPs与PEI-MSN之间的静电作用,导致mAPOE-AuNPs与PEI-MSN分离,PEI-MSN内包载的葡萄糖分子从MSN的孔隙中释放出来,然后利用二硫化钼纳米片(MoS2NSs)的过氧化物酶活性,对释放出来的葡萄糖进行比色分析,从而间接实现对Aβo的光学检测。Aβo标准曲线的线性范围为1.0~20 nmol·L^(-1),检出限为0.4 nmol·L^(-1)。按照标准加入法进行回收试验,回收率为98.0%~110%,测定值的相对标准偏差(n=6)为1.9%~2.7%。A novel and simple colorimetric probe(PEI-MSN/mAPOE-AuNPs),capable of efficiently determination ofβ-amyloid oligomer(Aβo)based on PEI functionalized mesoporous silica nanoparticles(PEI-MSN)loaded with glucose signaling molecules and mAPOE polypeptide-labeled gold nanoparticles(mAPOE-AuNPs),was constructed by combining competitive displacement reaction with colorimetric analysis together.Negatively charged mAPOE-AuNPs were electrostatically adsorbed on the surface of positive charge PEI-MSN to encapsulate glucose signaling molecules into mesoporous silica nanoparticles(MSN)pores.When Aβo was introduced to this system,mAPOE-AuNPs and PEI-MSN were separated owing to the larger specific force between Aβo and mAPOE polypeptide than the electrostatic interaction between mAPOE-AuNPs and PEI-MSN,causing the release of glucose molecules contained in PEI-MSN from the pores of MSN.Therefore,indirect colorimetric analysis for Aβo was developed by detecting the leaked glucose using the peroxidase activity of molybdenum disulfide nanosheets(MoS2NSs).Linear range of the standard curve for Aβo was 1.0-20 nmol·L^(-1),with detection limit of 0.4 nmol·L^(-1).Test for recovery was made by standard addition method,giving results in the range of 98.0%-110%,with RSDs(n=6)of the determined values in the range of 1.9%-2.7%.

关 键 词：比色探针 竞争置换 分光光度法 葡萄糖 β-淀粉蛋白寡聚体(Aβo) 

分 类 号：O657.32[理学—分析化学]