Redispersible spray-dried lipid-core nanocapsules intended for oral delivery: the influence of the particle number on redispersibility

Abstract

This study proposes a new approach to produce easily redispersible spray-dried lipid-core nanocapsules (LNC) intended for oral administration, evaluating the influence of the particle number density of the fed sample. The proposed approach to develop redispersible spray-dried LNC formulations intended for oral route is innovative, evidencing the needing of an optimization of the initial particle number density in the liquid suspension of nanocapsules. A mixture of maltodextrin and L-leucine (90:10 w/w) was used as drying adjuvant. Dynamic light scattering, turbidimetry, determination of surface area and pore size distribution, electron microscopy and confocal Raman microscopy (CRM) were used to characterize the proposed system and to better understand the differences in the redispersion behavior. An easily aqueous redispersion of the spray-dried powder composed of maltodextrin and L-leucine (90:10 w/w) was obtained, depending on the particle number density. Their surface area decreased in the presence of LNC. CRM enabled the visualization of the spatial distribution of the different compounds in the powders affording to better understand the influence of the particle number density of the fed sample on their redispersion behavior. This study shows the need for optimizing initial particle number density in the liquid formulation to develop redispersible spray-dried LNC powders.

Redispersible Spray-Dried Powder Containing Nanoencapsulated Curcumin: the Drying Process Does Not Affect Neuroprotection In vitro

“…As previously reported, blank LNC and the mixture of leucine/maltodextrin can be differentiated based on their unique Raman spectra (19). In the present study, the spatial component distribution within the SD-LNC-C was visualized.…”

“…To overcome this drawback, some technological strategies like freeze-drying, spray-drying and wet granulation have been proposed to convert polymeric nanocapsules into powders (16)(17)(18)25,26). More recently, the formulation of redispersible spray-dried LNC was reported by our research group (19). However, in that previous study, there was no drug loaded in the LNC.…”

“…Employing the process parameters previously described by de Andrade et al (19), spray-dried curcumin-loaded lipidcore nanocapsule (SD-LNC-C) powders were prepared using a Buchi Mini Spray Dryer B-290 (Buchi, Switzerland), which contained a nozzle with a cap orifice diameter of 0.7 mm. The drying adjuvant, composed of a blend of maltodextrin and Lleucine (90:10 w/w), was added to the LNC-C suspension at a final concentration of 5% (w/v) (19). Twenty minutes before the drying process, the blend of adjuvants was dissolved, under magnetic stirring, in 25 mL of ultrapure water, followed by a mixture with 25 mL of the LNC-C suspension.…”

“…A confocal pinhole of 50-μm rejected signals from out-of-focus regions, and the × 50 magnification objective (Epiplan Neofluar, Zeiss, Germany) with a N.A. 0.8 was applied (19). Image pixels assigned to LNC-C were depicted in yellow, whereas drying adjuvant (maltodextrin and L-leucine) spectra were depicted in blue.…”

“…Hence, spraydrying has been proposed as a technology to obtain dry powders containing LNC (15)(16)(17)(18). Our research group recently showed the recovery of the physicochemical properties of LNC after the redispersion of their spray-dried powders in water, using a blend of hydrophilic adjuvants in the drying process (19).…”