The subject of this study is comparison of imidazolium based dynamic and covalent coatings of the quartz capillary wall on the example of catecholamines determination. A way of synthesis of covalent coatings was proposed. For the first time different type of on-line sample preconcentration techniques (field-amplified sample stacking (FASS), head-column field amplified sample stacking (HC FASS), electrostacking, sweeping) were performed for catecholamines determination in N-alkylsubstituted imidazolium coated capillary. It was found that long chain imidazolium ionic liquids (CMImCl and CMImCl) in background electrolyte content create a dynamic coating of the quartz capillary walls and generate anode electroosmotic flow. Same is true for covalent coatings based on N-alkylsubstituted imidazolium. Both coatings prevent sorption of catecholamines on the internal surface of the quartz capillary. As a result efficiency and peak symmetry are increased. The maximum stacking efficiency factor (SEF) values for dynamic coatings were in range of 70-85, and limits of detection (LODs) were about 0.05 µg/ml under sweeping condition (micelle forming agent - CMImCl) when the electric conductivity of sample matrix was higher than electric conductivity of BGE. In case of covalent coating, the maximum SEF values were higher than 1000, and LODs were about 1-2 ng/ml under sweeping condition (micelle forming agent - sodium dodecyl sulphate) in combination with electrostacking.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.talanta.2018.05.057 | DOI Listing |
Mol Pharm
January 2025
Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs, School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
Developing low-toxicity, high-efficacy, and fast-acting strategies to manage acute liver injury (ALI) is critical due to its rapid progression and potential for severe outcomes. Curcumin (CUR) has shown promise in ALI therapy due to its ability to modulate the inflammatory microenvironment by scavenging reactive oxygen species (ROS). Nevertheless, CUR is highly hydrophobic limiting its bioavailability and effective in vivo transport, which hinders its further application.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan.
Here, "direct click bonding" of solid materials is proposed, which is the direct bonding of solid surfaces via the formation of covalent bonds without any adhesive. The present study shows that the Cu-free Huisgen 1,3-dipolar cycloaddition reaction proceeds between solid surfaces displaying cyclooctyne and azide groups, and it achieved the strong bonding of dissimilar solid materials as a macroscopic reaction. The bonding strength obtained is sufficiently high for practical use, and the strength can be controlled by the surface density of the cyclooctyne groups.
View Article and Find Full Text PDFFood Res Int
January 2025
State Key Laboratory of Marine Food Processing and Safety Control, Dalian Polytechnic University, Dalian 116034, Liaoning, China. Electronic address:
The acidophilic and heat-resistant characteristics of Alicyclobacillus acidoterrestris (A. acidoterrestris) pose significant challenges to fruit juice production. Traditional thermal removal methods are often ineffective against this resilient bacterium.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, CNRS UMR 5223, Ingénierie des Matériaux Polymères, F-69621 Cédex, France. Electronic address:
Passerini reaction was advantageously exploited to hydrophobize carboxymethyl cellulose (CMC) and alginates (ALG) by employing various hydrophobic aldehydes and isocyanides. The Passerini reaction, carried out in ecofriendly conditions, allowed to design never described twofold hydrophobized polysaccharide derivatives via the covalent grafting of two hydrophobic moieties. The modified CMC and ALG products were in-depth characterized to guaranty the success of the modification and to calculate the degrees of substitution (DS).
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
University Clinic of Navarra Centre for Applied Medical Research, 31008 Pamplona, Spain.
Experimental reproducibility in organ-on-chip (OOC) devices is a challenging issue, mainly caused by cell adhesion problems, as OOC devices are made of bioinert materials not suitable for natural cellularization of their surfaces. To improve cell adhesion, several surface functionalization techniques have been proposed, among which the simple use of an intermediate layer of adsorbed proteins has become the preferred one by OOC users. This way, the cells use surface receptors to adhere to the adsorbed proteins, which are in turn attached to the surface.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!