Download iGC-SEA Application Notes
| Application Note 202 – Determination of the dispersive surface energy of Paracetamol by pulse inverse gas chromatography at infinite dilution. |
 pdf |
| Application Note 204 – Determination of the glass transition temperatures Tg of maltose and its dependence on relative humidity by infinite dilution inverse gas chromatography. |
pdf |
| Application Note 215 – A sorption study on microporous materials by finite dilution inverse gas chromatography. | pdf |
| Application Note 216 – Characterisation of surface properties of glass fibres by inverse gas chromatography. |
pdf |
Application Notes By Request
| IGC Application Note 201 | Polymorphism in Spray Dried Lactose – Gas diffusion effects become stronger at lower rates of flow as evidenced experimentally by IGC peak shapes. At higher flow rates equilibrium cannot be assumed and adsorption will be less than at equilibrium state. This application note shows how to find a compromise between the two. Elution studies were performed on alpha-Lactose-Monohydrate with cyclohexane in the infinite dilution range. |
| IGC Application Note 203 | Heat of sorption studies on micro crystalline cellulose by pulse inverse gas chromatography at infinite dilution – Inverse gas chromatography provides a fast and accurate method to measure the heat of sorption over different concentration and temperature ranges. Moreover iGC SEA also allows the study of this parameter at different relative humidities. This paper describes the determination of the heat of desorption of octane on microcrystalline cellulose at infinite dilution and two different humidities. |
| IGC Application Note 205 | The determination of the solubility parameter of different starch types by infinite dilution inverse gas chromatography – Solubility parameters are directly related to the cohesive energy density of a material. The latter is a measure for the strength of interaction between molecules and atoms; therefore, the solubility parameter can be used to predict the stability of food ingredients, polymers, drugs or excipients. Inverse Gas Chromatography provides a fast and sensitive route for the measurement of this parameter. This paper describes the determination of the solubility parameter of starch measured by water at infinite dilution |
| IGC Application Note 206 | Determination of permeability coefficients of alkanes in polyethylene powder by infinite dilution inverse gas chromatography – The diffusion of solvent molecules in polymers can be measured rapidly and accurately by IGC at any concentration. At infinite dilution the van Deemter equation can be applied to obtain bulk diffusion coefficients. This paper demonstrates the performance of IGC measurements for the diffusion of octane in polyethylene. |
| IGC Application Note 207 | Characterisation of drug polymorphs by inverse gas chromatography – Two polymorphs of the same active pharmaceutical material were characterised by infinite dilution inverse gas chromatography. Clear differences were observed in the surface properties despite the chemically identical nature of the samples. The sensitivity of the technique may be of considerable use in the identification of batch-to-batch variations, polymorphic forms being one cause of this problem. |
| IGC Application Note 208 | The measurement of isotherms by pulse inverse gas chromatography – Isotherm measurements provide the means to calculate BET surface areas and pore size distribution functions. Standard measurements at 77 K are restricted to very few probe molecules. Moreover, these temperatures cause long measurement times despite that they are less relevant in practical terms. Inverse Gas Chromatography provides a fast and accurate isotherm measurement in a wide temperature range and with various probe molecules. This is demonstrated in this paper by hexane and cyclohexane sorption measurements on different oxides. |
| IGC Application Note 209 | An investigation of Chromosorb silicas as support materials for inverse gas chromatography – Chromosorb materials are interesting candidates for the support of viscous liquids in inverse gas-solid and gas-liquid chromatography. The tests conducted in this study include the determination of the material surface energy and its specific interaction with a range of polar probes. |
| IGC Application Note 210 | Investigation of the influence of bleaching conditions on surface properties of standard hair samples by inverse gas chromatography – The surface energy is a useful parameter describing the energetic properties of the surface of a solid sample. It can be determined in a fast and accurate way by inverse gas chromatography (IGC SEA). This paper describes the application of this approach for the investigation of how different bleaching conditions can cause changes on the surface of standard hair samples. |
| IGC Application Note 211 | An investigation of minerals used in asphalt by inverse gas chromatography – The affinity of minerals to bitumen is highly important for the quality of the asphalt composition. In order to predict this affinity a detailed knowledge of the physico-chemical properties of the mineral surface is required. Inverse Gas Chromatography (IGC SEA) is a fast and sensitive method for the characterisation of solid powders. In the current study dispersive as well as acid-base properties have been investigated for different minerals. |
| IGC Application Note 212 | The characterisation of amorphous materials by inverse gas chromatography – The amorphous state of differently processed lactose samples has been studied by Inverse Gas Chromatography at infinite dilution. The dispersive surface energy was taken as a measure for the energetic state of the samples. Significant differences were found independent of particle size and amorphous content. The observed differences confirm distinctive amorphous states although the experiments allow no conclusion as to whether or not this is due to poly-amorphism. The varying changes in surface energy with amorphous content further suggest that the location and distribution of the amorphous phase within a crystalline matrix also affects the results. |
| IGC Application Note 213 | Determination of thermodynamic parameters by frontal inverse gas chromatography – Strongly adsorbing materials are sometimes difficult to measure by pulse IGC SEA since peaks become very broad and flat at infinite dilution conditions. An increase in temperature or concentration could change the surface thermodynamics significantly. An alternative method is the application of the frontal method at infinite dilution. This was until now difficult to realise since advanced instrumentation is required. This paper describes frontal measurements using the SMS-iGC SEA at low concentration and temperature. The heat of sorption on carbon blacks is determined as an example for a typical infinite dilution property. |
| IGC Application Note 214 | The determination of the permeability and the activation energy of diffusion of drug powders by infinite dilution inverse gas chromatography – IGC SEA provides an easy and quick route for the determination of diffusion coefficients of solvents in powders and films. The determination of the diffusion coefficient in drug powders is performed by applying the van Deemter approach at infinite dilution. A measurement of this property at different temperatures also provides the activation energy for the diffusion process. |
| IGC Application Note 215 | A sorption study on microporous materials by finite dilution inverse gas chromatography – Finite concentration IGC SEA is a useful tool for the investigation of surface and pore properties. A novel combination of finite concentration IGC SEA and thermal desorption provides the possibility to separate micropore adsorption from surface and mesopore adsorption. This allows the calculation of BET values with physical relevance for highly microporous materials and the consideration of molecular sieve effects. |
| IGC Application Note 216 | Characterisation of surface properties of glass fibres by inverse gas chromatography – In the present paper dispersive surface energies and specific free energies have been calculated for different modified E-glass fibre surfaces. Both different sizing and different polymer coatings have been investigated to consider changes in the surface chemistry and surface energy during different fibre treatments. |
| IGC Application Note 218 | The determination of the Hildebrandt solubility parameter of polymethyl methacrylate by infinite dilution inverse gas chromatography – Solubility parameters are directly related to the cohesive energy density of a material. The latter is a measure of the strength of interaction between molecules or atoms, therefore, solubility parameters are related to stability and other physical properties. Inverse Gas Chromatography provides a fast and reliable route for the measurement of these parameters. This paper describes the determination of the Hildebrandt solubility parameter of PMMA and investigates the influence of different types of Chromosorb, which is used as a carrier for the coated polymer. |
| IGC Application Note 219 | The characterisation of surface area and surface adsorption potential heterogeneity profiles of hair by inverse gas chromatography – In this application note inverse gas chromatography was used to determine the surface area and adsorption potential distributions of nine different hair samples. The distribution function reflects the energetic heterogeneity profile of a surface and provides interesting information on the nature and population of different surface sites. In this study IGC SEA is shown to be a fast and accurate technique for the determination of these distribution functions. |
| IGC Application Note 220 | The characterisation of cotton fabrics and the interaction with perfume molecules by inverse gas chromatography – IGC SEA is a versatile tool in the characterisation of textile products and the interaction with perfume molecules due to the wide range of physicochemical parameters, which can be determined by this technique. This is demonstrated by means of cotton wool and cotton fabrics. Alkanes, fragrance molecules and other polar probes have been used to measure interaction parameters such as dispersive surface energy and specific free energy. Experiments at different relative humidities gave additional information about the impact of water adsorption on the measured properties. |
| Application Note 221 | The determination of acid-base parameters by inverse gas chromatography – IGC SEA is a versatile tool in the characterisation of textile products and the interaction with perfume molecules due to the wide range of physicochemical parameters, which can be determined by this technique. This is demonstrated by means of cotton wool and cotton fabrics. Alkanes, fragrance molecules and other polar probes have been used to measure interaction parameters such as dispersive surface energy and specific free energy. Experiments at different relative humidities gave additional information about the impact of water adsorption on the measured properties. |
| Application Note 222 | The determination of surface adsorption potential heterogeneity profiles on graphite by inverse gas chromatography – In this application note the adsorption potential distribution of two different graphite samples has been determined by Inverse Gas Chromatography (IGC SEA). This distribution function reflects the energetic heterogeneity profile of a surface and provides therefore interesting information on the nature and population of different surface chemical sites. In this study IGC SEA is shown to be a fast and accurate technique for the determination of these energy distribution functions. |
| Application Note 223 | Determination of energy parameters on microporous activated carbons – In the present paper the dispersive surface energy and specific energies of interaction for three microporous activated carbons have been calculated from IGC SEA measurements. The enhanced adsorption potential in the micropores requires a measurement temperature of at least 350 °C to achieve equilibrium conditions. |
| Application Note 224 | Surface energetic heterogeneity profiles by iGC surface energy analyzer – Surface energy is a useful parameter describing the energetic properties of the surface of a solid sample. Inverse gas chromatography (IGC) is an established and versatile tool in determining the surface free energy of solids by adsorption of vapours with known properties. This application note describes measurement of surface energetic heterogeneity of D-mannitol samples, with and without surface methylation. Second generation IGC instrument: iGC SEA is proven to be a fast and accurate energy mapping technique, generating highly reproducible surface energy data. |
| Application Note 227 | Determination of acid-base component of the surface energy by inverse gas chromatography – This paper describes the application of the IGC SEA technique to determine the Acid-Base component of the surface energy of solid samples. The acid-base surface energy of a solid can be determined using two mono-polar probes and the van Oss-Chaudhury and Good approach. The applied mono-polar probes have different acid-base strengths so the calculated solid acid-base surface energy values can vary. Also the result can vary as a function of the reference scale chosen (either Della Volpe or vOCG). This note discusses the limitation of current theories. |
| Application Note 301 | An Overview of iGC-SEA- A new instrumental technique for characterising the physico-chemical properties of pharmaceutical materials – This application note gives a brief description of the inverse gas chromatography technique, the IGC-Surface Energy Analyser instrument and some examples of its application within pharmaceutical physico-chemical analysis. |
| Application Note 302 | An overview-characterisation of strong solid-vapour interactions by inverse gas chromatography – Inverse Gas Chromatography (iGC SEA) is a very versatile technique for the characterisation of different types of material. This Application note focuses on the investigation of strong probe molecule – surface interactions and describes appropriate iGC SEA experiments for their investigation. |
| Application Note 303 | An overview of iGC-SEA – A new instrumental technique for characterising the physico-chemical properties of polymers – The surface properties of powders and fibres are important parameters in the handling and performance of a wide range of solid materials. iGC SEA has been specifically designed to address many of the issues faced by physical properties researchers, including fully automated operation and the ability to measure samples in a controlled humidity environment. This Application note gives a brief description of the technique, the instrument and some examples of its application to a range of polymeric materials analysis problems. |
| Application Note 304 | An overview of characterisation of alumina and related surfaces by inverse gas chromatography – The flexibility of the IGC SEA method makes it a valid tool in the characterization of various materials. This is the reason for its frequent use in the characterization of metal oxides, especially for catalyst supports. This paper will give an overview of IGC SEA application in the field of alumina and related oxides. |
| Request Application Note |
