Processing of Lipid Nanodispersions into Solid Powders by Spray Drying

Area of Science:

• Pharmaceutical Technology
• Materials Science
• Chemical Engineering

Background:

• Lipid nanodispersions are effective carriers for poorly water-soluble active pharmaceutical ingredients (APIs), improving bioavailability.
• Oral administration of APIs is preferred by patients, necessitating the development of solid dosage forms from nanocarrier systems.
• Spray drying offers a potential method for producing stable, solid-state nanocarrier formulations.

Purpose of the Study:

• To evaluate spray drying as a method for producing stable lipid nanodispersions for oral drug delivery.
• To investigate the influence of matrix materials and drying parameters on the nanoparticulate properties of lipid nanodispersions.
• To assess the redispersibility and particle size of spray-dried lipid nanoemulsions loaded with an active pharmaceutical ingredient.

Main Methods:

• Preparation of lipid nanodispersions using various solid lipids and oils.
• Spray drying of nanodispersions using lactose and SDS as matrix materials.
• Characterization of nanoparticulate properties, including particle size and redispersibility.
• Investigation of the effect of drying air inlet temperature on matrix formation and particle stability.
• Development of a tristearin suspension probe to measure particle temperature exposure during spray drying.

Main Results:

• Nanoparticulate properties of lipid nanodispersions were maintained during spray drying using lactose and SDS as matrix materials.
• Spray-dried lipid nanoemulsions loaded with fenofibrate showed good redispersibility with particle sizes below 300 nm at 26.8 wt.% lipid content.
• Optimal drying air inlet temperatures of 110 °C or above facilitated the formation of an amorphous lactose matrix around lipid particles.
• The tristearin probe indicated that particle temperatures during spray drying could exceed the measured outlet temperature.

Conclusions:

• Spray drying is a viable technology for producing stable, solid lipid nanocarrier systems for oral administration of poorly water-soluble APIs.
• Lactose in combination with SDS is an effective matrix system for spray drying lipid nanodispersions, preserving their nanoparticulate integrity.
• Controlling spray drying temperature is crucial for achieving an amorphous matrix and ensuring the stability and redispersibility of the nanocarriers.
• Further investigation into the precise temperature experienced by lipid particles during spray drying is warranted.