This work investigates the impact of conduit geometry on the chromatographic performance of typical particulate microchip packings. For this purpose, high-performance liquid chromatography (HPLC)/UV-microchips with separation channels of quadratic, trapezoidal, or Gaussian cross section were fabricated by direct laser ablation and lamination of multiple polyimide layers and then slurry-packed with either 3 or 5 microm spherical porous C8-silica particles under optimized packing conditions. Experimentally determined plate height curves for the empty microchannels are compared with dispersion coefficients from theoretical calculations. Packing densities and plate height curves for the various microchip packings are presented and conclusively explained. The 3 microm packings display a high packing density irrespective of their conduit geometries, and their performance reflects the dispersion behavior of the empty channels. Dispersion in 5 microm packings correlates with the achieved packing densities, which are limited by the number and accessibility of corners in a given conduit shape.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/ac902069x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Compact photometric detector integrated with separation microchip for potential portable liquid chromatography system.
J Chromatogr A
August 2024
The Ministry of Education Key Laboratory of Micro/Nano Systems for Aerospace, Department of Microsystem Engineering, School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China. Electronic address:
In recent years, miniaturized analytical instruments have been developing to meet the needs of portable and rapid analysis. The key of miniaturized analytical equipment is the miniaturization and integration of functional modules. This paper aims to develop a miniaturized photometric detector and separation microfluidic chip for a liquid chromatography (LC) system.
View Article and Find Full Text PDF[Applications of high performance liquid chromatography-mass spectrometry in proteomics].
Se Pu
July 2024
Department of Chemistry, Fudan University, Shanghai 200438, China.
Proteomics profiling plays an important role in biomedical studies. Proteomics studies are much more complicated than genome research, mainly because of the complexity and diversity of proteomic samples. High performance liquid chromatography-mass spectrometry (HPLC-MS) is a fundamental tool in proteomics research owing to its high speed, resolution, and sensitivity.
View Article and Find Full Text PDFRapid detection of glycosylated hemoglobin levels by a microchip liquid chromatography system in gradient elution mode.
Anal Chim Acta
February 2024
The Ministry of Education Key Laboratory of Micro/Nano Systems for Aerospace, Department of Microsystem Engineering, School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an, 710072, China. Electronic address:
Background: The determination of glycosylated hemoglobin (HbA) is crucial for diabetes diagnosis and can provide more substantial results than the simple measurement of glycemia. While there is a lack of simple methods for the determination of HbA using a point-of-care test (POCT) compared to glycemia measurement. In particular, high-performance liquid chromatography (HPLC) is considered the current gold standard for determining HbA levels.
View Article and Find Full Text PDF[Advances in chiral separation and analysis by capillary electrophoresis-mass spectrometry].
Se Pu
June 2022
Faculty of Chemistry, Northeast Normal University, Changchun 130024, China.
Most drugs used to treat diseases are chiral compounds. Drug enantiomers possess similar physical and chemical properties but may feature distinct pharmacological activities. Drug enantiomers may also exhibit different or even opposite functionalities for metabolism, in terms of the metabolic rate and toxicity in the body.
View Article and Find Full Text PDFPolysilicon Microchips Functionalized with Bipyridinium-Based Cyclophanes for a Highly Efficient Cytotoxicity in Cancerous Cells.
ACS Nano
April 2022
Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
The use of micrometric-sized vehicles could greatly improve selectivity of cytotoxic compounds as their lack of self-diffusion could maximize their retention in tissues. We have used polysilicon microparticles () to conjugate bipyridinium-based compounds, able to induce cytotoxicity under regular intracellular conditions. Homogeneous functionalization in suspension was achieved, where the open-chain structure exhibits a more dense packing than cyclic analogues.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!