Department of Chemistry and Biochemistry , University of Texas at El Paso , 500 West University Avenue , El Paso , Texas 79968 , United States.
Hamon Center for Therapeutic Oncology Research, Departments of Surgery and Pharmacology , University of Texas Southwestern Medical Center , 6000 Harry Hines Blvd , Dallas , Texas 75390 , United States.
Anal Chem. 2018 May 1;90(9):5930-5937. doi: 10.1021/acs.analchem.8b00842. Epub 2018 Apr 17.
The exploration of new physical and chemical properties of materials and their innovative application in different fields are of great importance to advance analytical chemistry, material science, and other important fields. Herein, we, for the first time, discovered the photothermal effect of an iron oxide nanoparticles (NPs)-mediated TMB (3,3',5,5'-tetramethylbenzidine)-HO colorimetric system, and applied it toward the development of a new NP-mediated photothermal immunoassay platform for visual quantitative biomolecule detection using a thermometer as the signal reader. Using a sandwich-type proof-of-concept immunoassay, we found that the charge transfer complex of the iron oxide NPs-mediated one-electron oxidation product of TMB (oxidized TMB) exhibited not only color changes, but also a strong near-infrared (NIR) laser-driven photothermal effect. Hence, oxidized TMB was explored as a new sensitive photothermal probe to convert the immunoassay signal into heat through the near-infrared laser-driven photothermal effect, enabling simple photothermal immunoassay using a thermometer. Based on the new iron oxide NPs-mediated TMB-HO photothermal immunoassay platform, prostate-specific antigen (PSA) as a model biomarker can be detected at a concentration as low as 1.0 ng·mL in normal human serum. The discovered photothermal effect of the colorimetric system and the developed new photothermal immunoassay platform open up a new horizon for affordable detection of disease biomarkers and have great potential for other important material and biomedical applications of interest.
探索材料的新物理和化学性质及其在不同领域的创新应用，对于推动分析化学、材料科学和其他重要领域的发展具有重要意义。在此，我们首次发现了氧化铁纳米粒子（NPs）介导的 TMB（3,3',5,5'-四甲基联苯胺）-HO 比色体系的光热效应，并将其应用于开发一种新的 NPs 介导的光热免疫分析平台，用于使用温度计作为信号读取器进行可视化定量生物分子检测。通过夹心型概念验证免疫分析，我们发现氧化铁 NPs 介导的 TMB 单电子氧化产物（氧化 TMB）的电荷转移复合物不仅表现出色变，而且还具有很强的近红外（NIR）激光驱动光热效应。因此，氧化 TMB 被探索为一种新的灵敏光热探针，通过近红外激光驱动的光热效应将免疫分析信号转化为热量，从而实现使用温度计的简单光热免疫分析。基于新的氧化铁 NPs 介导的 TMB-HO 光热免疫分析平台，以前列腺特异性抗原（PSA）作为模型生物标志物，在正常人血清中的检测浓度低至 1.0 ng·mL。所发现的比色体系的光热效应和开发的新光热免疫分析平台为经济实惠地检测疾病生物标志物开辟了新的前景，并为其他重要的材料和生物医学应用提供了巨大的潜力。
