SEM investigation of the shape, particle size and surface texture of Lactose and Theophylline (Fig. 2 ) formulation were carried out using a Jeol 6060LV SEM (Jeol Ltd., UK). A sample of the powder formulation was scattered onto the aluminium stage stub, by a gentle tapping motion, to provide a thin layer that was suitable to view the particles. The movement of the sample was restricted by adhering the sample to a double-sided conductive carbon adhesive tape (Agar Scientific, UK). As the sample is non-conductive, the sample was coated with a thin layer of gold (15 to 20 nm) (Quorum Technologies Ltd., UK) using a Quorum SC7620 Sputter Coater (Quorum Technologies Ltd., UK).![]()
SEM images of Theophylline formulation; a). Commercial Theophylline, b). Spry dried Theophylline, c). α-lactose monohydrate, d). Lactose and Theophylline in the formulation.