PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 12412125

A dynamically modified microfluidic poly(dimethylsiloxane) chip with electrochemical detection for biological analysis.

Yue-Hua Dou·Ning Bao·Jing-Juan Xu·Hong-Yuan Chen
View original source ↗Export metadata ↓

Abstract

Separation and direct detection of amino acids, glucose and peptide in a 3.1 cm separation channel made of poly(dimethylsiloxane) (PDMS) with end-column amperometric detection at a copper microdisk electrode was developed. This system is the integration of a normal sized working electrode with electrochemical detection on a PDMS microfabricated device. The PDMS channels dynamically modified by 2-morpholinoethanesulfonic acid (MES) show less adsorption and more enhanced efficiency than that of unmodified ones when applied to separations of these biological molecules. The migration time is less than 100 s and the reproducibility of migration time is satisfactory with relative standard deviation (RSD) of 2.8% in 19 successive injections. The limits of detection of arginine (Arg), glucose, and methionine-glycine (Met-Gly) are estimated to be 2.0, 8.5, and 64.0 microM at S/N = 3, approximately 0.5-16.0 fmol, respectively. Variances influencing the separation efficiency and amperometric response, including injection, separation voltage, detection potential, or concentration of buffer and additive, are assessed and optimized.

Explore related subjects

Alkanesulfonic AcidsAmino AcidsArginineDimethylpolysiloxanesDipeptidesElectrochemistryElectrophoresis, CapillaryGlucoseMicrochemistryMiniaturizationMorpholinesSurface PropertiesSurface-Active AgentsJournal ArticleResearch Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yue-Hua Dou, Ning Bao, Jing-Juan Xu, Hong-Yuan Chen. 2002. A dynamically modified microfluidic poly(dimethylsiloxane) chip with electrochemical detection for biological analysis.. https://doi.org/10.1002/1522-2683(200210)23%3A20%3C3558%3A%3Aaid-elps3558%3E3.0.co%3B2-%23

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Perfluorooctane sulfonate drives the synergistic dissemination of antimicrobial resistance and pathogenicity during sludge anaerobic digestion.

Per- and polyfluoroalkyl substances, one of the most prevalent and persistent emerging contaminants in sludge, may drive the dissemination of antimicrobial resistance and pathogenicity during sludge treatment. However, the mechanisms underlying perfluorooctane sulfonate (PFOS)-mediated propagation of antibiotic resistance genes (ARGs) and virulence factors (VFs) remain poorly understood. This study investigated the effects of PFOS (1 and 10 μg/g-dw) on ARGs dynamics and virulence risks. Quantitative PCR and metagenomic analysis revealed that PFOS stress led to the widespread enrichment of ARGs, the total abundance of mobile genetic elements (MGEs) and VFs also increased by 33.22-37.62% and 6.71-8.41%, respectively. Metagenomic binning results demonstrated that most metagenome-assembled genomes carrying ARGs or VFs simultaneously harbored MGEs. Mechanistically, excessive reactive oxygen species production and enhanced substrate-level phosphorylation for ATP generation may contribute to the increased horizontal transfer potential of ARGs under PFOS stress, which further facilitated the convergence of antimicrobial resistance and virulence traits within pathogens. Furthermore, PFOS may have hindered the negative regulation of the RhlI/RhlR quorum sensing system on the Type III secretion system, stimulating the secretion of VFs. This study elucidates the mechanisms by which PFOS promotes the dissemination of ARGs and pathogenicity during anaerobic digestion, highlighting the potentially overlooked environmental health risks of PFOS during sludge disposal.

Alkanesulfonic Acids↗
PubMed2007

Crystal structure of human dual specificity phosphatase, JNK stimulatory phosphatase-1, at 1.5 A resolution.

Human JNK stimulatory phosphatase-1 (JSP-1) is a novel member of dual specificity phosphatases. A C-terminus truncated JSP-1 was expressed in Escherichia coli and was crystallized using the sitting-drop vapor diffusion method. Thin-plate crystals obtained at 278 K belong to a monoclinic space group, C2, with unit-cell parameters a = 84.0 A, b = 49.3 A, c = 47.3 A, and beta = 119.5 degrees , and diffract up to 1.5 A resolution at 100 K. The structure of JSP-1 has a single compact (alpha/beta) domain, which consists of six alpha-helices and five beta-strands, and shows a conserved structural scaffold in regard to both DSPs and PTPs. A cleft formed by a PTP-loop at the active site is very shallow, and is occupied by one sulfonate compound, MES, at the bottom. In the binary complex structure of JSP-1 with MES, the conformations of three important segments in regard to the catalytic mechanism are not similar to those in PTP1B. JSP-1 has no loop corresponding to the Lys120-loop of PTP1B, and tryptophan residue corresponding to the substrate-stacking in PTP1B is substituted by alanine residue in JSP-1.

Alkanesulfonic Acids↗
PubMed2007

First comprehensive investigation of Suzuki couplings of alkenyl nonaflates with aryl and alkenyl boronic acid derivatives by using classical conditions and microwave heating.

Alkenyl nonaflates (nonafluorobutanesulfonates) are excellent substrates in a variety of palladium-catalysed coupling reactions. We herein demonstrate that bicyclic nonaflates generated from 8-heterobicyclo[3.2.1]octan-3-one derivatives can be coupled with aryl or alkenyl boronic acids in a very efficient manner. The resulting densely functionalised bicyclic skeletons are highly suitable for further synthetic elaboration. The thermal Suzuki couplings provided the expected products in moderate to good yields. Microwave (MW) irradiation dramatically shortened reaction times and gave superior results. Bisboronic ester 19 was also coupled with bicyclic nonaflates, for example, with 14, and double Suzuki-coupling products, such as 22, were isolated in good yields. We demonstrated the great synthetic potential of aryl-substituted 8-heterobicyclo[3.2.1]octene derivatives, such as 15, by the stereoselective conversion of this compound into highly substituted furanose 31 or substituted pyran derivative 33, which were obtained in short and efficient reaction sequences.

Alkanesulfonic Acids↗