组成图示
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传感器类型
荧光生物传感器
检测对象
卡铂（carboplatin）-DNA相互作用、对乙酰氨基酚（paracetamol）-DNA相互作用；样品基质：磷酸盐缓冲液（pH 7）中的DNA标记AuNPs溶液
检测原理
传感器以柠檬酸封端AuNPs为FRET供体，吸附在其表面的dsDNA碱基作为受体。未结合药物时，DNA碱基靠近AuNPs，发生FRET/静态猝灭，荧光较弱。卡铂与DNA结合或嵌入并破坏氢键，使DNA构象扩张，碱基与AuNPs距离增大，FRET效率下降，猝灭减弱，450 nm激发下荧光发射增强。卡铂浓度增加，结合量增加，荧光强度随之增强。对乙酰氨基酚仅弱结合，荧光变化小，可区分。荧光光谱仪读取发射强度。
检测灵敏度
卡铂: LOD: 0.450 mg/ml；斜率: 2.2541；R^2 = 0.9929；对乙酰氨基酚: LOD: 1.435 mg/ml；斜率: 0.2066；R^2 = 0.9965
效应效果
该传感器在体外磷酸盐缓冲液中对卡铂-DNA相互作用表现出明显荧光增强，而对乙酰氨基酚仅弱增强，显示对嵌入性细胞毒性药物与弱相互作用药物的区分能力。三次独立测量获得稳定回归：卡铂斜率2.2541、R^2=0.9929、LOD 0.450 mg/ml；对乙酰氨基酚斜率0.2066、R^2=0.9965、LOD 1.435 mg/ml。论文未报告RSD、实际样品回收率或与ELISA/HPLC/qPCR对比。作者认为方法快速、简单、低成本，可用于药物-DNA相互作用筛选、毒性研究和新药组合合成。
传感器的构成
- 纳米换能层：柠檬酸封端金纳米颗粒（citrate-capped AuNPs，HAuCl4/三钠柠檬酸还原制备），作为FRET供体和光学信号载体。
- 封端修饰层：三钠柠檬酸（trisodium citrate），包覆AuNPs表面并提供负电荷分散。
- 识别元件层：双链DNA（dsDNA，牛胸腺DNA），吸附于AuNPs表面，作为药物结合位点和FRET受体。
- 反应介质：磷酸盐缓冲液（phosphate buffer, pH 7），维持DNA构象与AuNPs分散。
- 信号读出：荧光光谱仪（Jasco FP-6500 spectrofluorometer），监测450 nm激发下荧光发射强度变化。
中文摘要
本研究利用DNA标记金纳米颗粒（AuNPs）构建光学纳米生物传感器，用于体外监测卡铂（carboplatin）与DNA的相互作用。卡铂是一种细胞毒性药物，在有效剂量下可产生肾毒性。该传感器基于荧光共振能量转移（FRET）原理：DNA标记AuNPs暴露于卡铂后，卡铂与DNA结合并引起复合物构象变化，使荧光分子或荧光/猝灭分子间距离减小，导致荧光强度增加。对乙酰氨基酚（paracetamol）作为对照药物，其与DNA相互作用较弱，荧光变化明显低于卡铂。结果表明，该光学传感器能够快速、有效地监测卡铂-DNA相互作用，检测限达0.45 mg/ml。该光学纳米生物传感器可用于新药组合合成过程中的药物-DNA相互作用研究。
英文摘要
The interaction of DNA and Carboplatin was studied with DNA labeled gold nanoparticles (AuNPs) based optical nanobiosensor. Carboplatin, a cytotoxic drug, is responsible for producing nephrotoxicity at effective dose. Thus, we have developed optical nanobiosensor for monitoring carboplatin-DNA interaction based on Fluorescence Resonance Energy Transfer (FRET) phenomenon. Paracetamol, an analgesic agent, was used as controlled drug in this study. The DNA labeled AuNPs, exposed to carboplatin, a binding event among the DNA and carboplatin takes place, resulting in a conformational change within the biosensor complex which decreases the distance among the fluorescent molecules or the fluorescent/quencher molecules. As the carboplatin interact with DNA, an increase in fluorescence intensity was observed. So, the major difference in increased fluorescence intensity between carboplatin-DNA and paracetamol-DNA interaction shows significant observations. Results have demonstrated that Optical sensor is able to rapidly and effectively monitor carboplatin-DNA interaction with a detection limit up to 0.45 μg/ml. This suggests that the developed optical nanobiosensor was ideal for monitoring Drug-DNA interaction studies while performing combinatorial synthesis for new drug development.