We studied fluorescence enhancements of fluorescein tethered to silver colloids of different size. Thiolated 23-mer oligonucleotide (ss DNA-SH) was bound selectively to silver colloids deposited on 3-aminopropyltriethoxysilane (APS)-treated quartz slides. Fluorescein-labeled complementary oligonucleotide (ss Fl-DNA) was added in an amount significantly lower than the amount of unlabeled DNA tethered to the colloids. The hybridization kinetics, observed as an increase in fluorescence emission, on small (30-40 nm) and large (> 120 nm) colloids were similar. However, the final fluorescence intensity of the sample with large colloids was about 50% higher than that observed for the sample with small colloids. The reference sample without ss DNA-SH was used to estimate the fluorescence enhancements of fluorescein tethered to the small colloids (E = 2.7) and to the large colloids (E = 4.1) due to its steady fluorescence signal. The proposed method, based on controlled hybridization with minimal amount of fluorophore labeled ss DNA, can be used to reliably estimate the fluorescence enhancements on any silver nanostructures.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763916 | PMC |
http://dx.doi.org/10.1002/bip.20179 | DOI Listing |
Small Methods
January 2025
National Engineering Research Center for Colloidal Materials, Key Laboratory of Colloid and Interface Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
Exploring potential third-order nonlinear optical (NLO) materials attracts ever-increasing attention. Given that the atomically precise and rich adjustable structural features of silver nanoclusters (Ag NCs), as well as the unique π-electron conjugated system of carbon-based nanomaterials, a supramolecular co-assembly amplification strategy to enhance the luminescent intensity and NLO performance of the hybrids of the two components, are constructed and the relationship between structures and optical properties are investigated. By combining water soluble Ag NCs [(NH)[Ag(mna)] (Hmna = 2-mercaptonicotinic acid, abbreviated to Ag─NCs hereafter) containing uncoordinated carboxyl groups with water-soluble fullerene derivatives modified with multiple hydroxyl groups (fullerenols, C─OH), the π-electron delocalization is expanded owing to non-covalent hydrogen bonding effect between Ag6─NCs and C─OH, which provides a feasible basis for realizing the NLO response.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Hubei Key Laboratory of Biomass Fibers and Eco-dyeing & Finishing, School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430200, PR China. Electronic address:
The catalytic reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP) is important in fine chemical synthesis, especially in the pharmaceutical, dye, and agrochemical industries. Sustainable methods are increasingly prioritized in these fields. Catalytic transfer hydrogenation (CTH) using formaldehyde (HCHO) as a hydrogen donor presents a safer and more environmentally friendly alternative due to its low-toxicity by-products and ease of handling.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
Cellulose is attracting considerable attention in the field of flexible electronics due to its unique properties and environmental sustainability, particularly as a substrate for flexible devices. Flexible photodetectors are an integral part of cellulose-based devices and have become essential in optical communication, heart rate monitoring, and imaging systems. The performance and adaptability of these photodetectors depend significantly on the quality of the flexible substrates.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Center of Excellence for Research in Engineering Materials (CEREM), Deanship of Scientific Research (DSR), King Saud University, Riyadh 11421, Saudi Arabia.
This study introduces a novel method to enhance the antibacterial functionality of electrospun nanofibrous textiles by integrating silver nanoparticles (AgNPs) into poly (lactic acid) (PLA) fabrics through pre- and post-electrospinning techniques. AgNPs were incorporated into hydrophobic and modified hydrophilic PLA textiles via pre-solution blending and post-solution casting. A PEG-PPG-PEG tri-block copolymer was utilized to enhance hydrophilicity and water stability, while AgNPs served as antibacterial agents.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Chirality epitomizes the sophistication of chemistry, representing some of its most remarkable achievements. Yet, the precise synthesis of chiral structures from achiral building blocks remains a profound and enduring challenge in synthetic chemistry and materials science. Here, we demonstrate that achiral colloidal nanocrystals, including Au and Ag nanocrystals, can assemble into long-range-ordered helical assemblies with the assistance of chiral molecules.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!