State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China.
State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China.
Anal Chim Acta. 2022 Dec 15;1236:340577. doi: 10.1016/j.aca.2022.340577. Epub 2022 Nov 2.
Plasmonic micro/nanobeads exhibit unique physicochemical properties attributed to their localized surface plasmon resonance (LSPR), enabling use in sensitive suspension array assays and matrix-assisted laser deposition/ionization mass spectrometry (MALDI-MS) analysis. Herein, we report a facile method for the preparation of magnetic plasmonic micro/nanobeads by the combination of Shirasu porous glass (SPG) membrane emulsification and polydopamine (PDA)-assisted in-situ reduction. The magnetic responsiveness properties endowed by doped FeO nanoparticles result in easy and complete separation of unwanted components during the preparation and bio-reaction processes. In addition, the coverage degree of the plasmonic shell can be flexibly controlled. As a result of the significant metal-enhanced fluorescence effect, as-prepared plasmonic microbeads enable the sensitive detection of alpha-fetoprotein (AFP) and deoxyribonucleotide (DNA) in suspension array with detection limits of 0.11 ng mL and 1.65 fmol mL, respectively, 8.6 times and 2 orders of magnitude higher than unmodified microbeads. Furthermore, as-prepared plasmonic nanobeads can be used as a matrix for MALDI-MS to allow the detection of low molecular weight biological molecules. As little as 0.2 pmol of proline and serine can be detected in a sample as small as 0.5 μL. This work provides a general strategy for the design of multifunctional plasmonic micro/nanomaterials that will help promote further advancements in sample analysis.
等离子体微/纳米珠由于其局域表面等离子体共振（LSPR）表现出独特的物理化学性质，可用于灵敏的悬浮阵列分析和基质辅助激光解吸/电离质谱（MALDI-MS）分析。在此，我们报告了一种通过 Shirasu 多孔玻璃（SPG）膜乳化和聚多巴胺（PDA）辅助原位还原相结合制备磁性等离子体微/纳米珠的简便方法。掺杂的 FeO 纳米粒子赋予的磁响应特性使得在制备和生物反应过程中容易且完全分离不需要的成分。此外，等离子体壳的覆盖度可以灵活控制。由于显著的金属增强荧光效应，所制备的等离子体微珠能够在悬浮阵列中灵敏地检测甲胎蛋白（AFP）和脱氧核苷酸（DNA），检测限分别为 0.11ng mL 和 1.65fmol mL，分别比未修饰的微珠高 8.6 倍和 2 个数量级。此外，所制备的等离子体纳米珠可用作 MALDI-MS 的基质，以允许检测低分子量生物分子。在 0.5 μL 小样本中，甚至可以检测到低至 0.2 pmol 的脯氨酸和丝氨酸。这项工作为多功能等离子体微/纳米材料的设计提供了一种通用策略，有助于推动样品分析的进一步发展。
