Effect of spray-drying temperature on the formation of flower-like lactose for griseofulvin loading
The effect of spray-drying temperature has been studied for the first time on the formation of flower-like lactose for drug loading in this work. The synthesis of the flower-like lactose involves two steps, namely spray drying and ethanol washing. Four inlet temperatures (140 °C, 150 °C, 160 °C and 200 °C) have been used in the spray-drying step. The effect of the spray-drying temperature was significant on the formation of flower-like lactose, in terms of crystallinity, porosity and drug loading capacity. Higher inlet temperatures are more likely to produce lactose in the β form. The engineered flower-like lactose is highly porous, with pores of 1.4, 3.4 and 29.3 nm (diameter). Compared with other inlet temperatures, the flower-like lactose dried at 150 °C has the lowest degree of crystallinity, the largest pore surface area (38 ± 4 m2/g) and pore volume (0.65 ± 0.09 cm3/g), and the highest griseofulvin loading capacity (16.2 ± 0.3%, w/w). A griseofulvin dissolution test has suggested that the flower-like lactose can be used as a drug carrier to enhance drug solubility.