Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

In this study, we report the synthesis and characterization of nitroxide-functionalized silica nanoparticles incorporating a TEMPO-based spin label. These nanoparticles were prepared through a reverse microemulsion method, and the nitroxide moiety was introduced via a TEMPO-modified silane, synthesized by coupling 4-amino-TEMPO with 3-(triethoxysilyl)propylsuccinic anhydride. By adjusting experimental parameters, we successfully modulated the radical surface density, obtaining values ranging from 0.36 to 2.83 radicals/nm, as determined by UV spectroscopy. Relaxometric measurements showed that both longitudinal () and transverse () relaxivities were strongly influenced by radical density, reaching maximum values of 5.42 and 11.94 s·mM, respectively, corresponding to enhancements of up to 489% () and 712% () compared to free 4-amino-TEMPO (at 20 MHz). Interestingly, high surface loading led to a decrease in relaxivity, highlighting the role of spin-spin interactions in modulating the relaxation process. Phantom electron paramagnetic resonance imaging (EPRI) demonstrated improved contrast and resolution for formulations with low radical densities, highlighting the importance of surface engineering to optimize the nanoparticle performance for EPRI applications.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.langmuir.5c01616DOI Listing

Publication Analysis

Top Keywords

silica nanoparticles
8
radical density
8
nitroxide-modified silica
4
nanoparticles impact
4
radical
4
impact radical
4
density relaxometric
4
relaxometric epr
4
epr properties
4
properties study
4

Similar Publications

Zeolitic imidazolate framework-8 nanoparticles: A promising nano-antimicrobial agent for sustainable management of bacterial leaf streak in rice.

Pestic Biochem Physiol

November 2025

State Key Laboratory of Agricultural and Forestry Biosecurity & Key Lab of Biopesticide and Chemical Biology, Ministry of Education, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China. Electronic address:

Rice bacterial leaf streak (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) significantly reduces rice yield and quality. Traditional chemical control methods often have limited efficacy and raise environmental concerns, highlighting the need for safer and more effective alternatives.

View Article and Find Full Text PDF

Glutathione-responsive and mitochondria targeting enhanced photodynamic therapy and cascade-triggered carbon monoxide release for all-in-one tumor therapy.

J Colloid Interface Sci

September 2025

School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China; Henan International Joint Laboratory of Smart Molecules and Identification and Diagnostic Functions, Henan Normal University, Xinxiang, Henan 453007, China. Electronic address:

Carbon monoxide (CO) has demonstrated significant potential in tumor therapy. However, the uncontrolled release of CO and single-modality therapy often fail to achieve the desired therapeutic outcomes. To address the above deficiencies, mesoporous silica nanoparticles containing tetrasulfide bonds (TMSNs) were constructed as intelligent nanocarriers to co-deliver a mitochondria-targeting photosensitizer (Au-TPP) and a photodynamically activated CO-releasing molecule (FeCO), enabling the synergistic combination of photodynamic therapy (PDT) and CO therapy.

View Article and Find Full Text PDF

Label-free immunoassay based on chemiluminescence-functionalized magnetic mesoporous nanoparticles for rapid detection of neuron-specific enolase.

Mikrochim Acta

September 2025

The Third Affiliated Hospital of Anhui Medical University, The First People's Hospital of Hefei, Binhu Hospital of Hefei, Hefei, 230061, P. R. China.

Lung cancer, as one of the cancers with the highest morbidity and mortality rates in the world, requires accurate detection of its vital serum marker, neuron-specific enolase (NSE), which is a key challenge for early detection of lung cancer. However, traditional chemiluminescence immunoassay (CLIA) methods rely on labeled antibodies (Abs) and suffer from complex operations and high costs. In this work, a label-free CLIA based on CL-functionalized mesoporous magnetic nanoparticles (CuFeO@mSiO-Cys-Luminol-Au NPs) is developed for the rapid and sensitive detection of NSE.

View Article and Find Full Text PDF

Atomic armor for thermal stability in nanoporous structures.

Proc Natl Acad Sci U S A

September 2025

School of Chemistry and Physics, Australian Research Council Research Hub in Zero-emission Power Generation for Carbon Neutrality, and Centre for Materials Science, Queensland University of Technology, Brisbane, QLD 4000, Australia.

Nanoporous structures play a critical role in a wide range of applications, including catalysis, thermoelectrics, energy storage, gas adsorption, and thermal insulation. However, their thermal instability remains a persistent challenge. Inspired by the extraordinary resilience of tardigrades, an "atomic armor" strategy is introduced to enhance the stability of nanoporous structures.

View Article and Find Full Text PDF