Transforming Lipid-Based Oral Drug Delivery Systems into Solid Dosage Forms: An Overview of Solid Carriers, Physicochemical Properties, and Biopharmaceutical Performance

Abstract

The diversity of lipid excipients available commercially has enabled versatile formulation design of lipid-based drug delivery systems for enhancing the oral absorption of poorly water-soluble drugs, such as emulsions, microemulsions, micelles, liposomes, niosomes and various self-emulsifying systems. The transformation of liquid lipid-based systems into solid dosage forms has been investigated for several decades, and has recently become a core subject of pharmaceutical research as solidification is regarded as viable means for stabilising lipid colloidal systems while eliminating stringent processing requirements associated with liquid systems. This review describes the types of pharmaceutical grade excipients (silica nanoparticle/microparticle, polysaccharide, polymer and protein-based materials) used as solid carriers and the current state of knowledge on the liquid-to-solid conversion approaches. Details are primarily focused on the solid-state physicochemical properties and redispersion capacity of various dry lipid-based formulations, and how these relate to the in vitro drug release and solubilisation, lipid carrier digestion and cell permeation performances. Numerous in vivo proof-of-concept studies are presented to highlight the viability of these dry lipid-based formulations. This review is significant in directing future research work in fostering translation of dry lipid-based formulations into clinical applications.

Lipid-Based Formulations Solidified Via Adsorption onto the Mesoporous Carrier Neusilin® US2: Effect of Drug Type and Formulation Composition on In Vitro Pharmaceutical Performance

“…Although several studies have shown that adsorbed LBFs can increase the oral bioavailability of poorly water‐soluble drugs, a previous study has shown that these adsorbed LBFs may still underperform relative to their liquid variants . The aim of the present study was to determine whether this phenomenon of incomplete desorption of LBF from a mesoporous adsorbent (Neusilin®) is a general effect that is applicable to a range of different drugs and LBF compositions and different simulated gastrointestinal conditions.…”

Development of a Solid Self‐Emulsification Delivery System for the Oral Delivery of Astaxanthin

“…The SEM images of solid carriers (silicon dioxide and anhydrous calcium hydrogen phosphate) and solid SEDS loaded astaxanthin are presented in Figure . It can be seen that they have large specific surface area with excellent sorption capacity . Figure A showed that the Silicon dioxide appeared to be spherical shaped with a lot of small opening on the surface.…”

QbD-based systematic development of novel optimized solid self-nanoemulsifying drug delivery systems (SNEDDS) of lovastatin with enhanced biopharmaceutical performance

“…Pre-dissolving the drugs in the blend of lipidic and emulsifying excipients omits the disintegration/dissolution steps, which are potential ratelimiting factors for oral absorption of poorly water-soluble drugs (Wu et al, 2006;Mu et al, 2013). Solid SNEDDS (S-SNEDDS) are relatively more recent technological modifications considered to be most sought after over the liquid SNEDDS, plausibly due to higher drug loading, better portability, improved stability and above all higher patient compliance (Bansal et al, 2008;Tan et al, 2013). Till date, most literature reports available on S-SNEDDS demonstrates the additional use of solidifying excipients including inert porous carriers, adsorbents, polymers along with equipmentintensive techniques like wet granulation, melt extrusion, extrusion-spheronization and spray drying for transformation of liquid SNEDDS into S-SNEDDS (Tang et al, 2008).…”