Poster Session B   |   7:00am Expo - Hall A & C   |   Poster ID #102

Nanoparticle-Mediated Quantitative Photothermal Biosensing for Cancer Early Diagnostics Using a Common Thermometer based on TMB Photothermal Effects

Academic Research
Prevention, Early Detection, Implementation, and Dissemination
FDA Status:
Not Cleared
CPRIT Grant:
Cancer Site(s):
All Cancers
Xiujun Li
The University of Texas at El Paso
Guanglei Fu
The University of Texas at El Paso
Rolf Brekken
The University of Texas Southwestern Medical Center
Robert Kirken
The University of Texas at El Paso


The exploration of new physical and chemical properties of materials and their innovative application in different fields is of great importance to advance analytical chemistry, material science, and biomedical applications. 


Herein, we, for the first time, discovered the photothermal effect of an iron oxide nanoparticles (NPs)-mediated TMB -H2O2 colorimetric system, and applied it toward the development of a new NP-mediated photothermal immunoassay platform for visual quantitative cancer biomarker 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-H2O2 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 a new horizon for affordable detection of disease biomarkers and other biomedical applications, especially for low-resource settings such as communities.