基于 CdTe@SiO 信号报告物的荧光免疫传感器用于前列腺特异性抗原的定量检测。

CdTe@SiO signal reporters-based fluorescent immunosensor for quantitative detection of prostate specific antigen.

机构信息

College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Shenzhen University, Shenzhen, 18060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China; School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA.

College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Shenzhen University, Shenzhen, 18060, China.

出版信息

Anal Chim Acta. 2019 May 30;1057:44-50. doi: 10.1016/j.aca.2019.01.019. Epub 2019 Jan 18.

DOI:10.1016/j.aca.2019.01.019

PMID:30832917

Abstract

In this paper, an immunosensor using CdTe@SiO core-shell nanoparticles as labels was constructed for highly sensitive detection of prostate-specific antigen (PSA). In this approach, CdTe@SiO core-shell nanoparticles were synthesized using the sol-gel method. The additional Cd ions and sulfur source in SiO shell can greatly enhance the fluorescence intensity of CdTe nanocrystals. The reason is the formation of CdS-like cluster in SiO shell, which reduced the quantum size effect. The obtained CdTe@SiO nanoparticles also exhibited excellent biocompatibility, which was ideal for applying in biomarker detection. Furthermore, PSA capture antibodies functionalized magnetic FeO nanoparticles (FeO-Ab) were utilized in the proposed immunosensor to capture and enrich the PSA. The captured PSA was then immuno-recognized by CdTe@SiO labeled with PSA detection antibodies (CdTe@SiOAb) by forming the sandwich complex FeO-Ab/PSA/Ab-CdTe@SiO. The construction of this immunosensor was confirmed by fluorescence spectroscopy. The proposed immunosensor showed a good linear relationship between the fluorescent intensity and the target PSA concentration ranging from 0.01 to 5 ng/mL, and a detection limit as low as 0.003 ng/mL was achieved. The sensor also exhibited good specificity to PSA. This highly sensitive and specific immunosensor has great potential to be used in other biological detection.

摘要

本文构建了一种基于 CdTe@SiO 核壳纳米粒子作为标记物的免疫传感器，用于高灵敏度检测前列腺特异性抗原（PSA）。在该方法中，采用溶胶-凝胶法合成了 CdTe@SiO 核壳纳米粒子。SiO 壳中的额外 Cd 离子和硫源可以极大地增强 CdTe 纳米晶体的荧光强度。原因是在 SiO 壳中形成了类似 CdS 的团簇，从而降低了量子尺寸效应。所得的 CdTe@SiO 纳米粒子还表现出优异的生物相容性，非常适合应用于生物标志物检测。此外，利用功能化磁性 FeO 纳米粒子（FeO-Ab）的 PSA 捕获抗体被应用于所提出的免疫传感器中，以捕获和富集 PSA。然后，通过形成夹心复合物 FeO-Ab/PSA/Ab-CdTe@SiO，用 PSA 检测抗体标记的 CdTe@SiO（CdTe@SiOAb）对捕获的 PSA 进行免疫识别。通过荧光光谱证实了该免疫传感器的构建。所提出的免疫传感器在 0.01 至 5ng/mL 的目标 PSA 浓度范围内表现出良好的荧光强度与靶 PSA 浓度之间的线性关系，检测限低至 0.003ng/mL。该传感器对 PSA 也表现出良好的特异性。这种高灵敏度和特异性的免疫传感器在其他生物检测中具有很大的应用潜力。