Surfactant Effect on the Physicochemical Characteristics of Solid Lipid Nanoparticles Based on Pillar[5]arenes

Novel monosubstituted pillar[5]arenes containing both amide and carboxyl functional groups were synthesized. Solid lipid nanoparticles based on the synthesized macrocycles were obtained. Formation of spherical particles with an average hydrodynamic diameter of 250 nm was shown for pillar[5]arenes containing N-(amidoalkyl)amide fragments regardless of their concentration. It was established that pillar[5]arene containing N-alkylamide fragments can form spherical particles with two different sizes (88 and 223 nm) depending on its concentration. Mixed solid lipid nanoparticles based on monosubstituted pillar[5]arenes and surfactant (dodecyltrimethylammonium chloride) were obtained for the first time. The surfactant made it possible to level the effect of the macrocycle concentration. It was found that various types of aggregates are formed depending on the macrocycle/surfactant ratio. Changing the macrocycle/surfactant ratio allows to control the charge of the particles surface. This controlled property will lead to the creation of molecular-scale porous materials that selectively interact with various types of substrates, including biopolymers.

Solid Lipid Nanoparticles Administering Antioxidant Grape Seed-Derived Polyphenol Compounds: A Potential Application in Aquaculture

The supply of nutrients, such as antioxidant agents, to fish cells still represents a challenge in aquaculture. In this context, we investigated solid lipid nanoparticles (SLN) composed of a combination of Gelucire® 50/13 and Precirol® ATO5 to administer a grape seed extract (GSE) mixture containing several antioxidant compounds. The combination of the two lipids for the SLN formation resulted in colloids exhibiting mean particle sizes in the range 139–283 nm and zeta potential values in the range +25.6–43.4 mV. Raman spectra and X-ray diffraction evidenced structural differences between the free GSE and GSE-loaded SLN, leading to the conclusion that GSE alters the structure of the lipid nanocarriers. From a biological viewpoint, cell lines from gilthead seabream and European sea bass were exposed to different concentrations of GSE-SLN for 24 h. In general, at appropriate concentrations, GSE-SLN increased the viability of the fish cells. Furthermore, regarding the gene expression in those cells, the expression of antioxidant genes was upregulated, whereas the expression of hsp70 and other genes related to the cytoskeleton was downregulated. Hence, an SLN formulation containing Gelucire® 50/13/Precirol® ATO5 and GSE may represent a compelling platform for improving the viability and antioxidant properties of fish cells.

Celecoxib-Loaded Solid Lipid Nanoparticles for Colon Delivery: Formulation Optimization and In Vitro Assessment of Anti-Cancer Activity

This work aimed to optimize a celecoxib (CXB)-loaded solid lipid nanoparticles (SLN) colon delivery system for the enhancement of anticancer activity. An ultrasonic melt-emulsification method was employed in this work for the preparation of SLN. The physical attributes were characterized for their particle sizes, charges, morphology, and entrapment efficiency (%EE), in addition to DSC and FTIR. The in vitro drug release profiles were evaluated, and the anticancer activity was examined utilizing an MTT assay in three cancer cell lines: the colon cancer HT29, medulloblastoma Daoy, and hepatocellular carcinoma HepG2 cells. All of the prepared SLN formulations had nanoscale particle sizes ranging from 238 nm to 757 nm. High zeta-potential values (mv) within −30 s mv were reported. The %EE was in the range 86.76–96.6%. The amorphous nature of the SLN-entrapped CXB was confirmed from SLN DSC thermograms. The in vitro release profile revealed a slow constant rate of release with no burst release, which is unusual for SLN. Both the F9 and F14 demonstrated almost complete CXB release within 24 h, with only 25% completed within the first 5 h. F9 caused a significant percentage of cell death in the three cancer cell lines tested after 24 h of incubation and maintained this effect for 72 h. The prepared CXB-loaded SLN exhibited unique properties such as slow release with no burst and a high %EE. The anticancer activity of one formulation was extremely significant in all tested cancer cell lines at all incubation times, which is very promising.

Applications of lipid-based nanocarriers for parenteral drug delivery

This review describes the use of Lipid-based Nanocarriers (LNCs) for the parenteral delivery of pharmaceutical actives. Firstly, the two generation of LNCs such as ‘‘solid lipid nanoparticles’’ (SLNs) and ‘‘nanostructured lipid carriers’’ (NLCs) are explained in term of preparation, characterization and stability. Although the use of LNCs through parenteral administration has shown many benefits, their use is limited by opsonization, an immune process that causes their short half-life (3-5 min). Therefore, many strategies are discussed to realize “stealth” systems suitable for parenteral administration. Successfully, the requirements and applications of parenteral lipid nanoparticles are reviewed for the delivery of natural compounds, synthetic drugs and genetic materials. In the last period, the latter application has been a remarkable interest due to the numerous benefits of mRNA vaccines to fight the Covid-19 pandemic.

Encapsulation of Flavonoids in Nanocarriers

The term “flavonoid” is a broad term given to the collection of natural polyphenolic compounds which occur in plants (fruits, vegetables, roots, flowers, stems, bark, leaves) as their secondary metabolites. Subsequent research reveals that flavonoids possess anti-inflammatory, anti-mutagenic, anti-oxidative, anti-ageing, and anti-carcinogenic effects along with their capacity to modulate enzymatic activities, inhibit cell proliferation, and inhibit bacterial growth, among others. The main shortcomings of oral administration of flavonoids as therapeutic that various studies have revealed are related to their stability, bioefficacy, and bioavailability. Novel nanotechnological strategies involving nanocarrier systems are proving promising to overcome the delivery challenge of flavonoids as therapeutics. Nanocapsules, nanospheres, solid lipid nanoparticles, nanoemulsions, micelles are examples of novel nanocarrier systems that are currently being explored for targeted and efficient bio functioning of flavonoids after their oral administration.