Shi Mingjun, Li Yang, Wang Wenqing, Han Rui, Luo Xiliang
Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
ACS Sens. 2024 Jun 28;9(6):2956-2963. doi: 10.1021/acssensors.4c00126. Epub 2024 May 22.
Overcoming the influence of interfering substances in the environment and achieving superior sensing performance are significant challenges in biomarker detection within complex matrices. Herein, an integrated electrochemical sensing platform for sensitive detection of biomarkers in complex biofluids was developed based on a newly designed PEGylated multifunctional peptide (PEG-MPEP). The designed PEG-MPEP contains a poly(serine) sequence (-ssssss-) as the antifouling part and recognition peptide sequence (-avwgrwh) specific for the target human immunoglobulin G (IgG). To improve the peptide stability to protease hydrolysis, d-amino acids were adopted to synthesize the whole peptide. Additionally, the PEGylation can further enhance the stability of the peptide, and the PEG itself was also antifouling, ensuring superstrong antifouling capability of the PEG-MPEP. The designed PEG-MPEP-based biosensor possessed a high sensitivity for the detection of IgG in the range of 1.0 pg mL to 1.0 μg mL, with a low limit of detection (0.41 pg mL), and it was capable of assaying targets accurately in real serum samples. Compared with conventional peptide-modified biosensors, the PEG-MPEP-modified biosensor exhibited superior antifouling and antihydrolysis properties in complex biofluid, showcasing promising potential for practical assay applications.
克服环境中干扰物质的影响并实现卓越的传感性能是复杂基质中生物标志物检测面临的重大挑战。在此，基于新设计的聚乙二醇化多功能肽（PEG-MPEP）开发了一种用于灵敏检测复杂生物流体中生物标志物的集成电化学传感平台。所设计的PEG-MPEP包含一个聚（丝氨酸）序列（-ssssss-）作为防污部分以及对目标人免疫球蛋白G（IgG）具有特异性的识别肽序列（-avwgrwh）。为提高肽对蛋白酶水解的稳定性，采用d-氨基酸合成整个肽。此外，聚乙二醇化可进一步增强肽的稳定性，且聚乙二醇本身也具有防污性，确保了PEG-MPEP具有超强的防污能力。所设计的基于PEG-MPEP的生物传感器对IgG的检测在1.0 pg/mL至1.0 μg/mL范围内具有高灵敏度，检测限低（0.41 pg/mL），并且能够在实际血清样本中准确测定目标物。与传统的肽修饰生物传感器相比，PEG-MPEP修饰的生物传感器在复杂生物流体中表现出卓越的防污和抗水解性能，展示了在实际检测应用中的广阔前景。
