Xie Jiaxiang, Xia Lixia, Huang Juan, Han Juan, Wang Zhining
Cardiovascular Surgery Department, The First Affiliated Hospital with Nanjing Medical University, Nanjing City, Jiangsu Province, 210029, China.
Oncology Department, Nanjing Mingji Hospital, No. 71, Hexi Street, Jianye District, Nanjing City, Jiangsu Province, 210000, China.
Anal Methods. 2025 Jul 3;17(26):5459-5465. doi: 10.1039/d5ay00197h.
Nursing hospital infections with () pose a significant risk to human health, especially to those immunosuppressed patients receiving surgical therapy. Consequently, it is imperative to create a novel and portable analysis method for the early diagnosis of infections. For sensitive and reliable analysis, we depict here a novel colorimetric approach based on rolling circle amplification (RCA) based construction of a detection scaffold and self-priming mediated signal recycling. In this method, the RCA product is attached to a plate surface to recognize targets and initiate the chain extension mediated cysteine catalytic oxidation based colorimetric reaction. This method involves activating RCA to generate several RCA products with repetitive functional portions by cyclizing the padlock sequence using primer sequences. To facilitate the color reaction based on gold nanoparticles, the produced G-rich sequences during the self-priming mediated signal recycling process can fold to G-quadruplex DNAzyme, which can catalyze the conversion of cysteine to cystine and produce color changes that can be observed directly with the naked eye. Based on this elegant design, the method has a broad detection range and a low limit of detection of 3.6 cfu mL. In addition, this colorimetric approach showed good selectivity to target bacteria. This technology has great potential for use in biomedical diagnostics and bio-sensing of pathogenic bacteria.
由（）引起的医院护理感染对人类健康构成重大风险，尤其是对那些接受手术治疗的免疫抑制患者。因此，迫切需要创建一种新颖且便携的分析方法用于（）感染的早期诊断。为了进行灵敏可靠的（）分析，我们在此描述一种基于滚环扩增（RCA）构建检测支架和自引发介导信号循环的新型比色法。在该方法中，RCA产物附着于平板表面以识别（）靶标并启动基于半胱氨酸催化氧化的链延伸介导比色反应。此方法包括通过使用引物序列环化锁式序列来激活RCA，以产生具有重复功能部分的多个RCA产物。为了促进基于金纳米颗粒的颜色反应，在自引发介导信号循环过程中产生的富含G的序列可折叠成G-四链体DNA酶，其可催化半胱氨酸转化为胱氨酸并产生肉眼可直接观察到颜色变化。基于这一精妙设计，该方法具有广泛的检测范围且检测限低至3.6 cfu/mL。此外，这种比色法对目标细菌显示出良好的选择性。该技术在生物医学诊断和病原菌生物传感方面具有巨大的应用潜力。
