Spray drying: From a traditional technology to modern biotechnological applications.

Spray drying, first patented in the late 19th century, has evolved into a versatile technology for converting liquid feeds into stable, free-flowing powders. Its fundamental strength lies in the rapid atomization and solvent evaporation. It enables precise control over particle size, morphology, and moisture content, making it a consolidated tool across food, chemical, and pharmaceutical industries. In the pharmaceutical field, it has been successfully applied to inhalable powders, amorphous solid dispersions, and controlled-release systems. At the same time, innovations in equipment design and Quality by Design strategies have improved robustness and scalability. Emerging applications now highlight its potential to stabilize biopharmaceuticals and vaccines, where dry powder formulations can enhance shelf life and reduce reliance on the cold chain. Similarly, spray drying has become central in nanomedicine through "nano-into-micro" engineering strategies that transform nanoscale carriers into inhalable or targeted dry powders. A further frontier is aseptic spray drying, which addresses sterility requirements for parenteral formulations and vaccines, representing a key step toward industrial adoption. This review outlines the fundamental principles of spray drying, examines the impact of formulation components, and discusses challenges in scale-up and industrial implementation. It then explores the most recent advances in biopharmaceuticals, nanomedicine, and aseptic processing, offering an integrated perspective on how spray drying is transitioning from a traditional drying method into a platform technology for modern biotechnology and pharmaceutical applications.