基于新型高效SERS传感器同步检测体液中多种致病菌耐药性的研究

Antibiotic resistance of bacteria is a key problem in the clinical treatment of infectious diseases, and it has received the extensive attention. The surface enhanced Raman scattering (SERS)biosensor is constructed by gold nanoplate array and gold nanorod, which are modified by 4-mercaptophenylboronic acid (4-MPBA) and the antibody, respectively. In the presence of pathogen, the sandwich composites are formed, which are composed of the substrate, pathogen and gold nanorod. A large amount of gold nanorods are absorbed on the surface of the pathogen, which is contributed to generate SERS hot spots, improving sensitivity on the biosensor. The bacteria, such as Mycobacterium tuberculosis causing tuberculosis, intestinal pathogenic escherichia coli and Pseudomonas aeruginosa causing secretory otitis media could be detected with the SERS biosensor. As polymixin was added onto the biosensor, they could destruct permeability of pathogen cell membrane in seconds. The process could be real-time monitored by SERS spectrum. The biosensor could be divided into multiple biochemistry reaction zones, where multiple reactions could conduct simultaneously. Our study suggests promising opportunities for development of high-efficacy multifunctional platforms for real-time detection of antibiotic resistance at the point-of-care.

致病菌耐药性是治疗临床感染性疾病的关键问题。本项目以4-巯基苯硼酸(4-MPBA)修饰的金纳米片阵列和抗体偶联的金纳米棒(金纳米探针)共同构筑表面增强强拉曼散射(SERS)传感器。致病菌出现时，表面吸附大量金纳米探针，形成“固相基底-致病菌-金纳米探针”复合物，以其热点效应提高SERS传感器灵敏度，实现对体液中致病性大肠杆菌(肠道致病菌)、结核分枝杆菌(肺结核致病菌)、绿脓杆菌(分泌性中耳炎致病菌)等多种致病菌的快速检测；继续向传感器滴加抗生素—多粘菌素，致病菌细胞膜的渗透性受到破坏数秒内死亡，SERS光谱可快速、直观的反映致病菌的这种生物化学变化，检出致病菌耐药性；该SERS传感器的多个生物化学单元能够同时进行上述反应，进而实现对各目标菌的高通量同步监控。本设计中的SERS传感器可作为一种通用实时检测平台，应用于生物医学和临床床边诊疗等领域。

致病菌耐药性是治疗临床感染性疾病的关键问题。本项目以构筑表面增强强拉曼散射(SERS)传感器，致病菌出现时，表面吸附大量金纳米探针，形成“固相基底-致病菌-金纳米探针”复合物，以其热点效应提高SERS传感器灵敏度，将实现对体液中致病性大肠杆菌(肠道致病菌)、结核分枝杆菌(肺结核致病菌)、绿脓杆菌(分泌性中耳炎致病菌)等多种致病菌的快速检测，除了致病菌检测外，如何快速有效的检测到致病菌的耐药性，对于及时控制细菌传播、疾病发生具有深远意义。因此构建高灵敏的SERS传感器能够有效的检测致病菌机器耐药性是一项极具挑战的工作。本项目在执行过程中，以大肠杆菌为测试对象，构建了label free 和label两种不同形式的SERS传感器有效进行大肠杆菌检测。其中label的SERS传感器还可以用于致病菌耐药性检测，耗时仅控制在3.5小时以内，本项目中还将细菌与小鼠血液进行混合，发现本传感器可以检测出大肠杆菌，表明本项目所研究的高灵敏SERS传感器有望临床快速诊疗中进行应用。