In this study halogen bonding (XB) is used as the driving force for the noncovalent assembly of gold nanoparticles (AuNPs) on silicon and quartz substrates functionalized with organic monolayers. The AuNPs are functionalized with XB-donor ligands, whereas the monolayers have pyridine groups as XB-acceptors. The surface-confined systems are formed by iteratively exposing the monolayers to solutions of organic cross-linkers having 2-4 pyridine groups and functionalized AuNPs. UV-vis spectroscopy, atomic force microscopy (AFM), and scanning electron microscopy (SEM) reveal how the structure of the resulting surface-bound assemblies are controlled by (i) the properties of the monolayers, (ii) the molecular structure and the number of XB binding sites of the organic cross-linker, and (iii) the number of functionalized AuNP and cross-linker deposition steps. Moreover, these structures exhibit surface-enhanced Raman scattering and significant changes are observed in the morphology of some of the surface-bound assemblies upon aging.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/nn201923q | DOI Listing |
J Colloid Interface Sci
January 2025
College of Light Industry and Food Engineering, Nanjing Forestry University, Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing 210037 China. Electronic address:
Surface-enhanced Raman scattering (SERS) is a highly sensitive technology to detect target analytes. The construction of dynamic "hot-spots" represents a significant approach to enhancing detection sensitivity. Herein, a hybrid plasma platform with dynamic "hot-spots" was developed for SERS recognition based on the assembly of gold nanospheres (AuNSs) on temperature-sensitive bacterial cellulose (BC) film grafted with poly(N-isopropylacrylamide) (PNIPAM).
View Article and Find Full Text PDFInt J Mol Sci
January 2025
School of Pharmaceutical Sciences, Jilin Medical University, Jilin 132013, China.
The association between microRNAs and various diseases, especially cancer, has been established in recent years, indicating that miRNAs can potentially serve as biomarkers for these diseases. Determining miRNA concentrations in biological samples is crucial for disease diagnosis. Nevertheless, the stem-loop reverse transcription quantitative PCR method, the gold standard for detecting miRNA, has great challenges in terms of high costs and enzyme limitations when applied to clinical biological samples.
View Article and Find Full Text PDFACS Sens
January 2025
Research Institute for Light-induced Acceleration System (RILACS), Osaka Metropolitan University, 1-2 Gakuencho, Nakaku, Sakai, Osaka 599-8570, Japan.
The unique characteristics of biological structures depend on the behavior of DNA sequences confined in a microscale cell under environmental fluctuations and dissipation. Here, we report a prominent difference in fluorescence from dye-modified single-stranded DNA in a light-induced assembly of DNA-functionalized heterogeneous probe particles in a microwell of several microliters in volume. Strong optical forces from the Mie scattering of microparticles accelerated hybridization, and the photothermal effect from the localized surface plasmons in gold nanoparticles enhanced specificity to reduce the fluorescence intensity of dye-modified DNA to a few %, even in a one-base mismatched sequence, enabling us to clearly highlight the single nucleotide polymorphisms in DNA.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4 6708 WE Wageningen, The Netherlands. Electronic address:
Unwanted nonspecific adsorption caused by biomolecules influences the lifetime of biomedical devices and the sensing performance of biosensors. Previously, we have designed B-M-E triblock proteins that rapidly assemble on inorganic surfaces (gold and silica) and render those surfaces antifouling. The B-M-E triblock proteins have a surface-binding domain B, a multimerization domain M and an antifouling domain E.
View Article and Find Full Text PDFAnal Chem
January 2025
School of Biomedical Engineering, Shenzhen Key Laboratory for Nano-Biosensing Technology, Guangdong Key Laboratory of Biomedical Measurements and Ultrasound Imaging, Marshall Laboratory of Biomedical Engineering, Shenzhen University Medical School, Shenzhen University, Shenzhen 518060, China.
Aggregation-induced emission (AIE) or aggregation-induced emission enhancement (AIEE) has endowed gold species with responsive fluorescent properties, favoring their potential applications in sensing, imaging, and therapy. However, it remains an interesting challenge to fabricate fluorophores with both AIE and AIEE effects. Herein, we presented highly luminescent Au(I) thiolate nanocomplex-based biosensors with Zn induced-AIE and zeolite imidazolate framework (ZIF-8) induced-AIEE effects.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!