Liu Jing, Chen Ye, Chen Feixiong
Department of Research, Shanghai University of Medicine and Health Sciences Affliated Zhoupu Hospital, The College of Medical Technology, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China.
Huangyan District Center for Disease Control and Prevention, Taizhou, Zhejiang 318020, China.
Langmuir. 2025 Apr 8;41(13):8647-8656. doi: 10.1021/acs.langmuir.4c05147. Epub 2025 Mar 27.
Magnetic nanoparticles (MNPs) are recognized as valuable tools for derived electrochemical biosensors and offer immense potential for the efficient diagnosis and detection of disease biomarkers. Herein, a new step-by-step approach for the development of multifunctional MNPs that exhibit both redox and biological properties is described. First, chemical cross-linking was employed to label these MNPs with redox dyes (ferrocene, anthraquinone, or methylene blue). Bovine serum albumin (BSA) was then applied as the terminal protective layer. Next, click chemistry was employed to engineer immunoglobulin G (IgG) onto the surface of these redox MNPs (IgG number of 35 ± 8 per MNP), providing multifunctionality. Before and after surface engineering, these MNPs exhibited high-quality size distributions, as characterized by differential centrifugal sedimentation (DCS). Square-wave voltammetry was used to reveal the presence of 21.8 ± 1.3 ferrocene molecules on each anti-CD63-based redox MNP, and the anti-CD63 antibodies still maintained their bioactivity toward the CD63 antigen. These multifunctional MNPs could be promising tools for advancing the development of MNP-assisted electrochemical biosensors and meeting the needs of single-nanoparticle electrochemistry.
磁性纳米颗粒（MNPs）被认为是用于衍生电化学生物传感器的有价值工具，并为疾病生物标志物的高效诊断和检测提供了巨大潜力。在此，描述了一种开发兼具氧化还原和生物学特性的多功能MNPs的新的逐步方法。首先，采用化学交联用氧化还原染料（二茂铁、蒽醌或亚甲基蓝）标记这些MNPs。然后将牛血清白蛋白（BSA）用作末端保护层。接下来，采用点击化学将免疫球蛋白G（IgG）工程化到这些氧化还原MNPs的表面（每个MNP的IgG数量为35±8），从而提供多功能性。在表面工程前后，通过差示离心沉降（DCS）表征，这些MNPs表现出高质量的尺寸分布。方波伏安法用于揭示每个基于抗CD63的氧化还原MNP上存在21.8±1.3个二茂铁分子，并且抗CD63抗体对CD63抗原仍保持其生物活性。这些多功能MNPs可能是推进MNP辅助电化学生物传感器发展和满足单纳米颗粒电化学需求的有前途的工具。
