High-speed analysis of residual solvents by flow-modulation gas chromatography
Rebecca E Wittrig1, Frank L Dorman, Christopher M English
1Restek Corporation, 110 Benner Circle, Bellefonte, PA 16823, USA.
Abstract:
High-speed gas chromatographic (GC) separation of residual solvents in pharmaceutical preparations, using a flow-modulation technique, is described. These volatile compounds are separated on a series-coupled (tandem) column ensemble consisting of a polyethylene glycol column and a trifluoropropylmethyl/dimethylpolysiloxane column. This column ensemble is operated in stop-flow mode to enhance, or "tune", the separation. A valve between the junction point of the tandem column ensemble and a source of carrier gas at a pressure above the GC inlet pressure is opened for intervals of 2-8 s. This stops or slightly reverses the flow of carrier gas in the first column. Stop-flow pulses are used to increase the separation of target analytes that overlap in the total ensemble chromatogram, compared to non-stop-flow, or conventional, operation. All 36 target compounds, based on ICH Classes I and II residual solvent lists, are resolved in 12 min using the stop-flow technique and a single chromatographic analysis.
More Related Videos
05:31Gas Chromatography-Mass Spectrometry Paired with Total Vaporization Solid-Phase Microextraction as a Forensic Tool
Published on: May 25, 2021
05:29Profiling Volatile Compounds in Blackcurrant Fruit using Headspace Solid-Phase Microextraction Coupled to Gas Chromatography-Mass Spectrometry
Published on: June 9, 2021
Related Concept Videos
Gas Chromatography–Mass Spectrometry (GC–MS)
A gas chromatograph consists of a long, narrow capillary column with a polysiloxane coating on the inner wall. The coating...
Gas Chromatography: Introduction
In GC, a sample is vaporized and mixed with an inert carrier gas (the mobile phase), which transports it through a column.
Supercritical Fluid Chromatography
SFC utilizes a supercritical fluid mobile phase,...
Gas Chromatography: Sample Injection Systems
Two primary injection methods are used...
High-Performance Liquid Chromatography: Elution Process
High-Performance Liquid Chromatography: Instrumentation
