Wang Han, Chen Zhituo, Li Taige, Xie Huimin, Yin Bohan, Wong Siu Hong Dexter, Shi Yaocheng, Zhang A Ping
Photonics Research Institute, Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
Center for Optical and Electromagnetic Research, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou 310058, China.
Biomed Opt Express. 2024 Apr 22;15(5):3240-3250. doi: 10.1364/BOE.523055. eCollection 2024 May 1.
Optofluidic devices hold great promise in biomedical diagnostics and testing because of their advantages of miniaturization, high sensitivity, high throughput, and high scalability. However, conventional silicon-based photonic chips suffer from complicated fabrication processes and less flexibility in functionalization, thus hindering their development of cost-effective biomedical diagnostic devices for daily tests and massive applications in responding to public health crises. In this paper, we present an optofluidic chip based on directly printed polymer optical waveguide Mach-Zehnder interferometer (MZI) sensors for label-free biomarker detection. With digital ultraviolet lithography technology, high-sensitivity asymmetric MZI microsensors based on a width-tailored optical waveguide are directly printed and vertically integrated with a microfluidic layer to make an optofluidic chip. Experimental results show that the sensitivity of the directly printed polymer optical waveguide MZI sensor is about 1695.95 nm/RIU. After being modified with capture molecules, i.e., goat anti-human immunoglobulin G (IgG), the polymer optical waveguide MZI sensors can on-chip detect human IgG at the concentration level of 1.78 pM. Such a polymer optical waveguide-based optofluidic chip has the advantages of miniaturization, cost-effectiveness, high sensitivity, and ease in functionalization and thus has great potential in the development of daily available point-of-care diagnostic and testing devices.
光流控设备因其具有小型化、高灵敏度、高通量和高可扩展性等优点，在生物医学诊断和检测领域具有巨大的应用前景。然而，传统的硅基光子芯片存在制造工艺复杂、功能化灵活性较差等问题，从而阻碍了其开发用于日常检测和应对公共卫生危机的大规模应用的经济高效的生物医学诊断设备。在本文中，我们展示了一种基于直接打印的聚合物光波导马赫-曾德尔干涉仪（MZI）传感器的光流控芯片，用于无标记生物标志物检测。利用数字紫外光刻技术，基于宽度定制光波导的高灵敏度非对称MZI微传感器被直接打印出来，并与微流体层垂直集成，制成光流控芯片。实验结果表明，直接打印的聚合物光波导MZI传感器的灵敏度约为1695.95 nm/RIU。在用捕获分子即山羊抗人免疫球蛋白G（IgG）进行修饰后，聚合物光波导MZI传感器能够在芯片上检测浓度为1.78 pM的人IgG。这种基于聚合物光波导的光流控芯片具有小型化、成本效益高、灵敏度高以及功能化简便等优点，因此在开发日常可用的即时诊断和检测设备方面具有巨大潜力。
