Determination of surface properties and how characteristics of salbutamol sulphate, before and after micronisation

Inverse gas chromatography (IGC) was employed to characterise the surface thermodynamic properties of two nominally equivalent batches of salbutamol sulphate and to highlight any surface energetic changes induced on micronisation. A powder flow avalanching analyser was used to probe the relationship between powder flow and the surface energetic properties. The results obtained demonstrate the potential of these techniques to detect and quantify differences in powder samples, before and after micronisation. They also indicate that surface energy differences detected by ICC can be related to important secondary processing properties such as powder flow. (C) 1998 Elsevier Science B.V. All rights reserved.