Gas-solid chromatographic determination of moisture in lyophilized pharmaceutical products
Related Experiment Video
Updated: Oct 24, 2026

Mass Spectrometric Approaches to Study Protein Structure and Interactions in Lyophilized Powders
Published on: April 14, 2015
Abstract:
A gas-solid chromatographic procedure is described for the analysis of low levels of moisture in individual lyophilized vials of pharmaceutical products. Dry ethanol, which contains methanol as the internal standard, is injected through the septum of the vial to dissolve the lyophilized contents. An aliquot of this solution is then withdrawn and injected onto a Porapak QS column at 110 degrees C where the components are separated and detected using thermal conductivity detection. A solvent blank correction allows quantitation of the water in the individual vial. The method is conveniently applied to samples containing as little as 50 microgram water/vial, and as many as 25 vials can be assayed/day. A simple technique is also described for removing water from the ethanol solvent to less than 100 ppm, using a molecular sieve.
More Related Videos
11:44Qualitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae Using 2D Gas Chromatography with Time-of-flight Mass Spectrometry
Published on: March 6, 2016
05:31Gas Chromatography-Mass Spectrometry Paired with Total Vaporization Solid-Phase Microextraction as a Forensic Tool
Published on: May 25, 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...
Sublimation
Volatilization
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.
Flame Photometry: Lab