PDF(Pubmed)
Abstract：
Alkaline phosphatase (ALP) is among the most studied enzymes by far, playing an important role in the metabolism of organisms and the regulation of protein activity. Herein, a label-free composite nanoprobe is constructed by combining inorganic nanomaterials and aggregation-induced emission (AIE) molecule to achieve highly sensitive and selective detection of ALP. Negatively charged 9,10-bis [2-(6-sulfonatopropoxyl) naphthylethenyl] anthracene (BSNVA) molecule is synthesized, which has the AIE performance and can be assembled on the surface of amino-SiO2 nanoparticles through electrostatic interaction for fluorescence enhancement. MnO2 nanosheets are rich in negative charges, enabling them to be wrapped on the surface of the amino-SiO2 nanosphere to shield the positive charge on its surface, making it impossible for BSNVA to accumulate on the surface and then weakening the bio-fluorescence of the system. Furthermore, with catalyzed substrates induced by ALP, generating ascorbic acid and the redox reaction between ascorbic acid and MnO2, the nanoprobe helps in realizing the high-sensitivity detection of ALP with a detection limit of 0.38 mU/mL. The proposed strategy requires no complex cleaning and modification processes and can overcome the quenching effect caused by the aggregation of traditional organic dyes, proving to be a simple, low-cost and \"turn-on\" fluorescent detection method for ALP.
摘要：
碱性磷酸酶（ALP）是迄今为止研究最多的酶之一，在生物体的代谢和蛋白质活性的调节中起着重要的作用。在这里，通过结合无机纳米材料和聚集诱导发射(AIE)分子来构建无标记复合纳米探针,以实现对ALP的高灵敏度和选择性检测。合成了带负电荷的9,10-双[2-（6-磺酸丙氧基）萘乙烯基]蒽（BSNVA）分子，它具有AIE性能，可以通过静电相互作用在氨基-SiO2纳米粒子表面组装以增强荧光。MnO2纳米片富含负电荷，使它们能够包裹在氨基-SiO2纳米球的表面上，以屏蔽其表面的正电荷，使得BSNVA不可能在表面上积累，然后削弱系统的生物荧光。此外，用ALP诱导的催化底物，纳米探针产生抗坏血酸和抗坏血酸与MnO2之间的氧化还原反应，有助于实现ALP的高灵敏度检测，检出限为0.38mU/mL。所提出的策略不需要复杂的清洁和改性过程，并且可以克服由传统有机染料聚集引起的猝灭效应，被证明是一个简单的，用于ALP的低成本和“开启”荧光检测方法。
