石墨烯量子点荧光探针对碱性磷酸酶活性的高效检测

基于苯醌类物质静态猝灭石墨烯量子点(GQDs)荧光的特性, 构建了一种利用GQDs荧光探针实时、 高效检测碱性磷酸酶(ALP)活性的新方法. 过氧化氢在辣根过氧化物酶催化作用下产生羟基自由基并将邻苯二酚氧化成邻苯醌, 导致GQDs的荧光猝灭. ALP催化抗坏血酸-2-磷酸反应生成抗坏血酸, 具有较强还原性的抗坏血酸能清除溶液中的过氧化氢和羟基自由基, 抑制邻苯醌的产生, 使GQDs的荧光猝灭效果减弱. 随着ALP活性的增大, GQDs在440 nm处的荧光强度不断增强, 由此建立了一种高效检测ALP活性的新方法. 在最佳实验条件下, 该GQDs荧光探针对ALP活性的检出限为0.084 U/L. 将此方法成功用于人血清中ALP活性的检测, 为与ALP相关疾病的诊断与治疗提供了理论基础.

Efficient Determination of Alkaline Phosphatase Activity Based on Graphene Quantum Dots Fluorescent Probes

Based on the static fluorescence quenching effects of benzoquinones on graphene quantum dots（GQDs）， a GQDs-based fluorescent probe was established to detect the activity of alkaline phosphatase（ALP）. Under the catalytic action of horseradish peroxidase， hydrogen peroxide（H₂O₂） could generate hydro-xyl radicals（·OH）， and ·OH oxidized o-dihydroxybenzene to produce o-benzoquinone subsequently， resul-ting in the fluorescence quenching of GQDs. ALP catalyzed the production of reductive ascorbic acid by ascorbic acid 2-phosphat. Ascorbic acid efficiently removed H₂O₂ and ·OH from the solution， leading to the inhibition of the production of o-benzoquinone and the fluorescence recovery of GQDs. Therefore， a highly sensitive determination strategy for ALP activity was established. Under the optimal experimental conditions， the detection limit of ALP activity was 0.084 U/L. This method was used to evaluate ALP activity in human serum samples. Such approach can provide theoretical basis for the diagnosis and treatment of ALP-related diseases.