KRAS G12C点突变水平被认为与非小细胞肺癌（NSCLC）的早期诊断密切相关。本研究基于氮掺杂石墨烯量子点（NGQDs）和光诱导电子/能量转移可逆加成-断裂链转移（PET-RAFT）信号放大策略，首次制备了一种新型电化学发光（ECL）生物传感器用于KRAS G12C突变的检测。利用简单的煅烧方法制备了作为ECL发光物种的NGQDs，其具有阴极ECL特性。首先，通过与发夹状DNA（hDNA）的特异性识别，捕获了KRAS G12C突变DNA，即目标DNA（tDNA）。然后，通过蓝光引发PET-RAFT反应，成功聚合了大量单体形成可控的聚合物链。最后，通过与N-(3-氨丙基)甲基丙烯酰胺盐酸盐（APMA）的酰胺化反应引入了大量NGQDs，显著增强了ECL信号强度。在最佳条件下，该传感器在10 fM至10 nM范围内实现了ECL强度与KRAS G12C突变水平对数的良好线性关系。此外，该策略对血清样本中KRAS G12C突变的检测展示了高选择性和优秀的适用性。因此，该生物传感器在临床诊断和实际应用中具有巨大潜力。©2023 Wiley-VCH GmbH.

The levels of KRAS G12C point mutation is recognized to be closely related to the earlier diagnosis of non-small cell lung cancer (NSCLC). Here, based on nitrogen-doped graphene quantum dots (NGQDs) and photo-induced electron/energy transfer reversible addition-fragment chain transfer (PET-RAFT) signal amplification strategy, we fabricated a novel electrochemiluminescence (ECL) biosensor for the detection of KRAS G12C mutation for the first time. NGQDs as ECL-emitting species with cathodic ECL were prepared by a simple calcination method. Firstly, KRAS G12C mutations DNA, i.e. target DNA (tDNA), was captured by specific identification with hairpin DNA (hDNA). Then, PET-RAFT was initiated by blue light, and large numbers of monomers were successfully polymerized to form controllable polymer chains. Lastly, massive NGQDs was introduced via amidation reaction with N-(3-aminopropyl)methacrylamide hydrochloride(APMA), which significantly amplified the ECL signal intensity. Under optimal conditions, this biosensor achieved a good linear relationship between ECL intensity and logarithm of the levels of KRAS G12C mutation in the range from 10 fM to 10 nM. Moreover, this strategy exhibited high selectivity and excellent applicability for KRAS G12C mutation detection in the serum samples. Therefore, this biosensor has great potential in clinical diagnosis and practical application.© 2023 Wiley-VCH GmbH.