Price, Duncan M.; Reading, Mike; Smith, Roger M.; Localized Evolved Gas Analysis using a Scanning Thermal Microscope. Proc. 28th North American Thermal Analysis Society Conference, October 4-6 (2000) Orlando, Florida, USA, pp. 705-709
Micro-thermal analysis employs a scanning probe microscope fitted with a miniature resistive heater/thermometer to obtain images of the surface of materials and then perform localized thermoanalytical measurements. We have demonstrated that it is possible to use the same configuration to pyrolyze selected areas of the specimen by rapidly heating the probe to 600-800°C. This generates a plume of evolved gases which can be trapped using a sampling tube containing a suitable sorbent placed close to the probe. Thermal desorption-gas chromatography/mass spectrometry can then be used to separate and identify the evolved gases. This capability expands the normal visualization and characterization by micro-thermal analysis to include the possibility of localized chemical analysis of the sample (or a domain, feature or contaminant). The isolation and identification of natural products from a plant leaf are presented as an example to illustrate this approach.