HSA/g-C_(3)N_(4)作为电致化学发光探针检测β-淀粉样蛋白

HSA/g-C_(3)N_(4) as an Electrochemiluminescent Probe for the Detection ofβ-Amyloid

采用一步煅烧法制备了一种电致化学发光(ECL)性能良好的类石墨相-碳化氮二维纳米材料(g-C_(3)N_(4)),经1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐和N-羟基琥珀酰亚胺活化后,g-C_(3)N_(4)与人血清白蛋白(HSA)复合,得到HSA/g-C_(3)N_(4)复合材料。利用Aβ与HSA的结合作用,将HSA/g-C_(3)N_(4)与不同浓度的β-淀粉样蛋白(Aβ)孵育,形成Aβ/HSA/g-C_(3)N_(4)。同时将巯基修饰的Aβ适体固定在金电极表面,通过适体与靶标的特异性结合,可以将Aβ/HSA/g-C_(3)N_(4)捕获到电极上。在共反应剂K2S2O8存在下,该传感器实现了对Aβ的ECL灵敏检测。研究表明,在10 fmol·L^(-1)到100 nmol·L^(-1)范围内,ECL强度与Aβ浓度具有良好线性关系,检出限低至7.2 fmol·L^(-1)。并且该传感器具有较高的灵敏度和较好的特异性。

In this work,two-dimensional graphite-like carbon nitride(g-C_(3)N_(4)),as an effective electrochemiluminescence(ECL)substrate,was prepared by one step calcination method.And human serum albumin(HSA)could bind to g-C_(3)N_(4) to form HSA/g-C_(3)N_(4) complexes after g-C_(3)N_(4) was activated by using 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride and N-hydroxysuccinimide.After incubating with amyloid-β(Aβ),Aβwas bound with HSA to form Aβ/HSA/g-C_(3)N_(4) complexes via HSA-Aβinteraction.Subsequently,the thiol-functionalized DNA aptamer,as the specific recognition element for Aβpeptide,was assembled on the gold electrode via Au-S interaction.The forming Aβ/HSA/g-C_(3)N_(4) complexes were then anchored on the electrode through the specific recognition between the target Aβand the aptamer.Under the optimized conditions,the present ECL sensor reveals a good linear response to Aβpeptide ranging from 10 fmol·L^(-1) to 100 nmol·L^(-1) with a detection limit of 7.2 fmol·L^(-1).This biosensor also shows good sensitivity and selectivity.