In this article, the dielectrophoretic (DEP) assembly of chemically-modified silica nanoparticles (SiNPs) was introduced. Five types of surface-modified SiNPs, including OH-SiNPs, COOH-SiNPs, CH(3)HPO(2)-SiNPs, PEG-SiNPs, and NH(2)-SiNPs, have been investigated. After applying an ac field with relatively high intensity and frequency, it was shown that only COOH-SiNPs and CH(3)HPO(2)-SiNPs could be self-assembled on the microelectrodes by the DEP forces. The results indicated that the anionic group modification could obviously enhance the DEP self-assembly of SiNPs on the microelectrodes. Then the DEP assembly of CH(3)HPO(2)-SiNPs was selected as a representative to be investigated further. By using Rubpy dye doped in the core of the CH(3)HPO(2)-SiNPs, the assembly process was visualized in real time by inverse fluorescence microscopy. Precise control over the frequency of the applied ac field showed that the DEP forces can assemble CH(3)HPO(2)-SiNPs from aqueous suspensions into submicrowires, and it was found that the number of assembled submicrowires between the microelectrode gaps could be well controlled with reversibility. Furthermore, the DEP assembly process of CH(3)HPO(2)-SiNPs was sensitive to the pH of the dispersed medium. These findings would provide a way to circumvent the difficulty in controlling the dielectrophoretic assembly process of nanoparticles and offer application opportunities for the DEP assembly of chemically modified SiNPs.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/la1019636 | DOI Listing |
Microbiome
October 2024
Quantitative and Computational Biology, Max-Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
Background: Metagenomics is a powerful approach to study environmental and human-associated microbial communities and, in particular, the role of viruses in shaping them. Viral genomes are challenging to assemble from metagenomic samples due to their genomic diversity caused by high mutation rates. In the standard de Bruijn graph assemblers, this genomic diversity leads to complex k-mer assembly graphs with a plethora of loops and bulges that are challenging to resolve into strains or haplotypes because variants more than the k-mer size apart cannot be phased.
View Article and Find Full Text PDFJ Environ Manage
November 2024
School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, PR China; Guangdong Engineering and Technology Research Center for Environmental Nanomaterials, Guangzhou 510006, PR China. Electronic address:
Biosensors (Basel)
August 2024
2020 X-Lab, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
Nat Commun
September 2024
Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China.
Talanta
December 2024
School of Chemical Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea. Electronic address:
For the protection of human health and environment, there is a growing demand for high-performance, user-friendly biosensors for the prompt detection of pathogenic bacteria in samples containing various substances. We present a nanogap electrode-based purely electrical impedimetric sensor that utilizes the dielectrophoresis (DEP) mechanism. Our nanogap sensor can directly and sensitively detect pathogens present at concentrations as low as 1-10 cells/assay in buffers and drinking milk without the need for separation, purification, or specific ligand binding.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!