3 research outputs found
Atomically Precise Au<sub>25</sub>(SG)<sub>18</sub> Nanoclusters: Rapid Single-Step Synthesis and Application in Photothermal Therapy
Remarkable
recent advances on Au<sub>25</sub>(SR)<sub>18</sub> nanoclusters have
led to significant applications in catalysis, sensing, and magnetism.
However, the existing synthetic routes are complicated, particularly
for the water-soluble Au<sub>25</sub>(SG)<sub>18</sub> nanoclusters.
Here, we report a single-step concentration and temperature-controlled
method for rapid synthesis of the Au<sub>25</sub>(SG)<sub>18</sub> nanoclusters in as little as 2 h without the need for low-temperature
reaction or even stirring. A systematic time-based investigation was
carried out to study the effects of volume, concentration, and temperature
on the synthesis of these nanoclusters. Further, we discovered for
the first time that the Au<sub>25</sub>(SG)<sub>18</sub> nanoclusters
exhibit excellent photothermal activities in achieving 100% cell death
for MDA-MB-231 breast cancer cells at a power of 10 W/cm<sup>2</sup> using an 808 nm laser source, demonstrating applications toward
photothermal therapy
Exploration of Nanoparticle-Mediated Photothermal Effect of TMB‑H<sub>2</sub>O<sub>2</sub> Colorimetric System and Its Application in a Visual Quantitative Photothermal Immunoassay
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)-H<sub>2</sub>O<sub>2</sub> 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-H<sub>2</sub>O<sub>2</sub> photothermal immunoassay platform, prostate-specific
antigen (PSA) as a model biomarker can be detected at a concentration
as low as 1.0 ng·mL<sup>–1</sup> 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
Capillary blood for point-of-care testing
<p>Clinically, blood sample analysis has been widely used for health monitoring. In hospitals, arterial and venous blood are utilized to detect various disease biomarkers. However, collection methods are invasive, painful, may result in injury and contamination, and skilled workers are required, making these methods unsuitable for use in a resource-limited setting. In contrast, capillary blood is easily collected by a minimally invasive procedure and has excellent potential for use in point-of-care (POC) health monitoring. In this review, we first discuss the differences among arterial blood, venous blood, and capillary blood in terms of the puncture sites, components, sample volume, collection methods, and application areas. Additionally, we review the most recent advances in capillary blood-based commercial products and microfluidic instruments for various applications. We also compare the accuracy of microfluidic-based testing with that of laboratory-based testing for capillary blood-based disease diagnosis at the POC. Finally, we discuss the challenges and future perspectives for developing capillary blood-based POC instruments.</p