Nanoparticles (NPs) are substances between 1 and 100 nm in size. They have been the subject of numerous studies because of their potential applications in a wide range of fields such as cosmetics, electronics, medicine, and food. For biological applications of nanoparticles, they are usually coated with a substance capable of preventing agglomeration of the nanoparticles and nonspecific binding and exhibiting water-solubility characteristics with specific immobilized (bio)molecules. In order to evaluate the chemical properties of the surface-modified nanoparticles for bioapplications, including drug delivery, a simple and reliable method for the analysis of the presence of the surface chemicals and the ligand states of the nanoparticles is necessary. In this study, the authors numerically evaluated the extent of polyethylene glycol (PEG) ligand conjugation on AuNPs by concurrently adopting a microliquid inkjet printing system for sampling of the PEGylated AuNPs solution and ToF-SIMS imaging together with statistical analysis. The statistical correlation values calculated from the signals of PEG and Au measured by ToF-SIMS imaging on the sample spots made by a microliquid inkjet printing system showed better reproducibility and improved correlation values compared to the pipet spotting. Their improved method will be useful to evaluate ligand-conjugated nanoparticles for quality control of each conjugation process.

中文翻译：

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使用ToF-SIMS和统计分析对聚乙二醇配体与金纳米颗粒表面结合的数值评估。

纳米颗粒（NPs）是大小在1到100 nm之间的物质。由于它们在化妆品，电子，医学和食品等广泛领域中的潜在应用，它们已成为众多研究的主题。对于纳米粒子的生物学应用，通常将它们涂覆有一种物质，该物质能够防止纳米粒子的团聚和非特异性结合，并具有特定固定化（生物）分子的水溶性特征。为了评估用于生物应用的表面改性的纳米粒子的化学性质，包括药物递送，需要一种简单可靠的方法来分析表面化学物质的存在和纳米粒子的配体状态。在这个研究中，作者通过同时采用微液体喷墨打印系统对PEG化AuNPs溶液进行采样和ToF-SIMS成像以及统计分析，对AuNPs上的聚乙二醇（PEG）配体结合程度进行了数值评估。由ToF-SIMS成像测量的PEG和Au信号对微液体喷墨打印系统制成的样品斑点的统计相关值显示出比移液管斑点更好的重现性和相关值。他们改进的方法将有助于评估配体共轭的纳米颗粒，以控制每个共轭过程的质量。由ToF-SIMS成像测量的PEG和Au信号对微液体喷墨打印系统制成的样品斑点的统计相关值显示出比移液管斑点更好的重现性和相关值。他们改进的方法将有助于评估配体共轭的纳米颗粒，以控制每个共轭过程的质量。由ToF-SIMS成像测量的PEG和Au信号对微液体喷墨打印系统制成的样品斑点的统计相关值显示出比移液管斑点更好的重现性和相关值。他们改进的方法将有助于评估配体共轭的纳米颗粒，以控制每个共轭过程的质量。