Development of Solid Lipid Nanoparticles as Dry Powder: Characterization and Formulation Considerations

Abstract

Solid lipid nanoparticles (SLNs) are lipid-based colloidal systems used for the delivery of active compounds. Although SLNs have many benefits, they show important issues due to physical and chemical instability phenomena during storage. For these reasons, it is highly desirable to have a dried SLN formulation available. Therefore, the aim of the project was to identify suitable methods to obtain a dry powder formulation from an SLN suspension. The nanoparticle suspension was dried using both freeze- and spray-drying techniques. The suitability of these methods in obtaining SLN dry powders was evaluated from the analyses of nanotechnological parameters, system morphology and thermal behavior using differential scanning calorimetry. Results pointed out that both drying techniques, although at different yields, were able to produce an SLN dry powder suitable for pharmaceutical applications. Noteworthily, the freeze-drying of SLNs under optimized conditions led to a dry powder endowed with good reconstitution properties and technological parameters similar to the starting conditions. Moreover, freeze–thaw cycles were carried out as a pretest to study the protective effect of different cryoprotectants (e.g., glucose and mannitol with a concentration ranging from 1% to 10% w/v). Glucose proved to be the most effective in preventing particle growth during freezing, thawing, and freeze-drying processes; in particular, the optimum concentration of glucose was 1% w/v.

Nanomedicines: Emerging Platforms in Smart Chemotherapy Treatment—A Recent Review

“…The lipid materials used in SLN formulation encompass a diverse range, including triglycerides (such as tristearin, tripalmitin, and trilaurin) [ 64 ], partial glycerides (like glyceryl behenate, glyceryl stearate, and glyceryl palmitostearate), fatty acids (including stearic acid, palmitic acid, and capric acid) [ 42 ], steroids (such as cholesterol), and waxes. Commonly used surfactants comprise poloxamers, lecithin, sodium glycocholate, polysorbates, sorbitan esters, and their mixtures [ 65 ]. SLNs offer protection to encapsulated drugs against chemical degradation and enable controlled drug release.…”

Archaeosomes for Oral Drug Delivery: From Continuous Microfluidics Production to Powdered Formulations

“…While some studies report on the use of archaeosomes as oral delivery systems for various drug molecules [12][13][14], limited information exists on how archaeosomes behave under different physiological conditions, interact with cells mimicking the GI tract, and whether archaeosomes, due to their pronounced stability, can be transformed into a solid dosage form. Dry powders can, for example, be produced by lyophilization [15,16] or spray-drying processes as already shown for liposomes or solid lipid nanoparticles [17,18]. However, heat and shear stress during manufacturing may lead to instability, enhanced particle aggregation, and rapid drug release, which limits pharmaceutical production on a large scale.…”