Related Experiment Video
Updated: Aug 18, 2026

Liquid Chromatography Coupled to Refractive Index or Mass Spectrometric Detection for Metabolite Profiling in Lysate-based Cell-free Systems
Published on: September 23, 2021
Online preconcentration of thyrotropin-releasing hormone (TRH) by SDS-modified reversed phase column for microbore
Rong Meng1, Wanlin Xia, Mats Sandberg
1Department of Chemistry, University of Pittsburgh, 603 Chevron Science Center, 219 Parkman Drive, Pittsburgh, PA 15260, USA.
Abstract:
Thyrotropin-releasing hormone (TRH, pGlu-His-Pro-amide) is an important tripeptide existing in biological systems at low concentrations. It is a fairly hydrophilic peptide, cationic in acidic solutions. Preconcentration online before reversed phase chromatography separation can enhance concentration detection limits of hydrophobic, but not hydrophilic species. The hydrophilic TRH can be preconcentrated using a reversed phase precolumn charged with sodium dodecyl sulfate (SDS). The separation also uses SDS. The preconcentration is effective for a microbore system, achieving detection limit of 250 pM for a sample size of 500 microl with electrochemical detection of the biuret complex formed post column. Preconcentration using an online precolumn is also effective in packed capillary high-performance liquid chromatography (HPLC) with a detection limit of 3 nM in 24 microl.
Related Concept Videos
High-Performance Liquid Chromatography: Introduction
In HPLC, two phases play a critical role in the separation process:
High-Performance Liquid Chromatography: Elution Process
High-Performance Liquid Chromatography: Instrumentation
