Objective: This work evaluates the potential of using fresh milk to deliver theophylline to children.
Methods: Theophylline-fresh milk systems were prepared using different solids ratios (0 : 1-1 : 0) and three fat contents in commercial milks (low, medium and high), which were spray-dried at different inlet air temperatures (Tinlet - 105, 130 and 150 °C). The process was evaluated for yield and the resulting powders for moisture content (MC), particle size and shape, density and wettability. Theophylline-milk potential interactions (differential scanning calorimetry (DSC) and FT-IR) and chemical (theophylline content) and microbiological stability of powders (shelf and in-use) were also evaluated.
Key findings: The production yield (13.6-76.0%), MC (0.0-10.3%) and contact angles in water (77.29-93.51°) were significantly (P < 0.05) affected by Tinlet , but no differences were found concerning the mean particle size (3.0-4.3 μm) of the different powders. The milk fat content significantly (P < 0.05) impacted on the density (1.244-1.552 g/cm3 ). Theophylline content remained stable after 6 months of storage, before extemporaneous reconstitution. After reconstitution in water, low-fat milk samples (stored at 4 °C) met the microbial pharmacopoeia criteria for up to 7 days. No theophylline-milk components interaction was observed.
Conclusion: Spray-dried milk-composed powders may be used as vehicles for theophylline delivery in paediatrics following further characterization and in-vivo evaluation.
Keywords: extemporaneous preparation; milk; paediatrics; spray drying; theophylline.
© 2016 Royal Pharmaceutical Society.