“…Whereas most clinical and synthetic lung surfactant formulations are liquids and consist of SP-B and/or SP-C (peptide mimics) in a phospholipid mixture, dry powder surfactant undergoes spray-drying steps aimed at controlling particle size, density, shape, charge, solid state, and hygroscopicity in order to manipulate agglomeration and powder blending ( 30 ). Formulation strategies may include the addition of hygroscopic excipients, such as sugars (e.g., lactose, trehalose, and mannitol) and sodium chloride, and/or dispersion enhancers, such as l-leucine, to alter particle-particle interaction forces and improve the deagglomeration of the fine particles ( 31 , 32 ). These newer micron-sized dry powder synthetic lung surfactant formulations, such as B-YL:Trehalose surfactant ( 21 , 31 ), are highly surface active, possess the required aerosolization characteristics, and are biophysically stable.…”