Optimization Of Spray Drying Conditions Research Articles

Optimization of spray-drying conditions using response surface methodology, physico-chemical characterization and shelf-life estimation of pineapple powder

Response surface methodology (RSM) was used in this study to optimize spray drying process conditions for pineapple juice powder (PJP) production.

Formulation and process considerations for the design of sildenafil-loaded polymeric microparticles by vibrational spray-drying

Context and objective: The current study reports the preparation and characterization of sildenafil-loaded poly(lactide-co-glycolide) (PLGA)-based microparticles (MPs) by means of vibrational spray-drying. Emphasis was placed on relevant formulation and process parameters with influence on the properties of obtained powders.Materials and methods, results and discussion: The solid state solubility of sildenafil in spray-dried PLGA-MPs amounted to 17 wt.%. Thus, a drug loading below and above the determined solubility limit resulted in solid solutions and phase separation (i.e. solid dispersions), respectively. Furthermore, interactions between sildenafil and the PLGA matrix were observed for the spray-dried MPs. Optimization of spray-drying conditions allowed for a fabrication of defined MPs (size range of ∼4–8 μm) displaying a high sildenafil encapsulation efficiency (>90%) and sustained sildenafil release (from ∼4 to >12 h). The individual drug release rates from the spray-dried formulations were mainly a function of the drug loading, applied polymer and MP size. Finally, a scale-up of the preparation process did not result in a relevant change of the physicochemical and in vitro drug release properties of the prepared powders.Conclusion: Identification of relevant formulation and spray-drying parameters enabled the fabrication of tailored sildenafil-loaded PLGA-based MPs, which meet the needs of the individual application (e.g. controlled drug delivery to the lungs).

Optimization of Spray-Drying Conditions and Pharmacodynamics Study of Theophylline/Chitosan/β-Cyclodextrin Microspheres

Theophylline has been reported to have considerable pharmacological activity for asthma, which is partly mediated by the anti-inflammatory effects of theophylline. Nevertheless, the wide application of theophylline was hampered due to its rapid metabolization and the poor patient compliance. Microspheres can be applied as targeted and sustained drug-release carriers. The purposes of the present study were to optimize spray-drying conditions and summarize the anti-asthma pharmacodynamics of the theophylline/chitosan/β-cyclodextrin microspheres. The yield, encapsulation efficiency, drug load, and water content were evaluated using ultraviolet spectrophotometry. The morphology of microspheres was observed by scanning electron microscope. Histopathological assessment of microspheres in a murine model of asthma was measured by H&E staining and immunohistochemistry. Levels of IL-4 and TNF-α protein in bronchoalveolar lavage fluid were measured using enzyme-linked immunosorbent assays. The optimal spray-drying conditions (T gi = 150°C, W ff = 8 mL/min, W af = 400 m3/h, and M w = 13 × 105) were selected by orthogonal experiment. The yield, encapsulation efficiency, drug load, and water content of the microspheres were 39.3 ± 1.2%, 76.0 ± 0.8%, 19.5 ± 1.5%, and 10.3 ± 0.6%, respectively. A scanning electron micrograph showed that the microspheres were predominantly spherical with smooth surface or slightly wrinkled. Theophylline/chitosan/β-cyclodextrin microspheres markedly decreased the number of infiltrated inflammatory cells, the levels of IL-4, and TNF-α protein in animal models. Based on lung histopathological studies, inflammatory cells, goblet cells, and NF-κB positive cells were inhibited in the theophylline/chitosan/β-cyclodextrin microspheres group compared with those in the model group. These results indicate that optimized theophylline/chitosan/β-cyclodextrin microspheres may be useful as a novelty pulmonary drug-delivery system in therapy for the treatment of bronchial asthma.