Comprehensive and comparative studies on nanocytotoxicity of glyceryl monooleate- and phytantriol-based lipid liquid crystalline nanoparticles

Lyotropic liquid crystalline nanoparticles of morin: An approach to improve pharmacokinetics and brain disposition in rats via nose-to-brain pathway

Morin (MOR) is a potent neuroprotective agent possessing exceptional antioxidant abilities. The significant challenges associated with MOR delivery are poor solubility and low permeability. The present work aims to develop nasal delivery of MOR using lyotropic liquid crystalline nanoparticles (LLCs). MOR LLCs were prepared via the hydrotrope method, and 3-factor, 2-level factorial design was chosen for optimization. The results indicated MOR LLCs exhibited cubic vesicular structure, were non-toxic to nasal mucosa, and depicted sustained in vitro release. Pharmacokinetic studies showed MOR LLCs resulted in 1.53-fold and 1.42-fold enhancement in area under the curve than plain MOR oral and nasal groups. The relative drug targeting efficiency and relative direct transport percentage were 1.99-fold and 1.14-fold higher for MOR LLCs than plain nasal MOR, representing efficient brain targeting via olfactory pathways. Nasal administration of MOR LLCs enhances brain targeting and offers a self-administration option for prolonged utilization to alleviate neurological conditions.

Nanoassemblies with Gd-chelating lipids (GMO@DTPA-BSA-Gd) as a potential new type of high molecular weight contrast agents

Self-assembled lipid nanoparticles containing Gd-chelating lipids are a new type of positive magnetic resonance imaging contrast agents (MRI CAs). High molecular weight imposes reduced molecular reorientation (τr) and corresponding longer reorientation correlation times (τc), finally resulting in overall high relaxivity (r1) of such contrast agents. Therefore, we report nanoassemblies based on two types of amphiphile molecules: glyceryl monooleate (GMO) as a matrix embedded with DTPA-bis(stearylamide) and its gadolinium salt (DTPA-BSA-Gd) as a Gd-chelating lipid, stabilized by surfactant Pluronic F127 molecules. The loading of DTPA-BSA-Gd into the GMO matrix was investigated at low (5% w/w) and high (30, 40, 50% w/w) contents. Small angle X-ray scattering (SAXS), cryogenic transmission electron microscopy (cryo-TEM) and dynamic light scattering (DLS) results show that although the nanoassembly of both amphiphile molecules within the nanoparticle is disturbed in terms of the formed phases, this composition ensures their colloidal stability. In nanoparticles with low DTPA-BSA-Gd contents, the assembly results in a cubic diamond phase that is co-existing with a fraction of liposomes. For high DTPA-BSA-Gd contents, swelling of the structure occurs such that the initially formed primitive cubic phase transforms toward a lamellar phase in the nanoassemblies. Results from inductively coupled plasma mass spectrometry (ICP-MS) indicate that for almost all systems, the loading efficiency (LE) of DTPA-BSA-Gd is high (reaching up to approx. 85%), and the nanoassembly provides strong entrapment of Gd3+ ions, which are then efficiently uptaken by cells. Moreover, the higher the surfactant content, the higher the LE. The viability studies demonstrate that the prepared nanoassemblies preserve high biocompatibility towards both cancer (HeLa) and normal cells (MSU 1.1). Nuclear magnetic resonance relaxometry studies (NMR relaxometry) followed by MRI on the prepared nanoassembly dispersions proved that the formation of GMO@DTPA-BSA-Gd nanoassemblies, considered as high molecular weight CAs, results in high relaxivity parameters (e.g., r1 = 19.72 mM-1 s-1 for 2GMO-40DTPA-10F127) that are superior to commercially developed ones (e.g., Magnevist or Gadovist). These comprehensive studies imply that a high degree of internal ordering of nanoassemblies with a higher content of Gd-chelating lipid is not a decisive factor in determining the increase in relaxivity, thus confirming their potential as positive MRI CAs.

Cubosomes as versatile lipid nanocarriers for neurological disorder therapeutics: a comprehensive review

Cubosomes are novel vesicular drug delivery systems with lipidic liquid crystal nanoparticles formed of predetermined proportions of amphiphilic lipids. They have a honeycomb-like structure and are thermodynamically stable. These bicontinuous lipid layers are separated into two water-based channels internally that can be used by various bioactive substances, including drugs, proteins, and peptides. This complex structure is responsible for its high drug-loading capacity. Cubosomes are thought to be promising vehicles for various routes of administration because of their extraordinary characteristics, including bioadhesion, the capacity to encapsulate hydrophilic, and hydrophobic, as well as amphiphilic substances, high resistance to environmental stress, and their ability to achieve controlled release through modification. One of the essential elements for improving patient compliance is the ability of these well-defined nano-drug delivery systems to boost the effectiveness of targeting while lowering the side effects/toxicities of payloads. The large internal surface area, a sufficiently uncomplicated fabrication procedure, and biodegradability make it an attractive nano lipid carrier for drug delivery. This review outlines the recent advancement of cubosomes for managing various neurological disorders, highlighting their potential in this field.

Tetrahedron clusters serving as a platform for foam-like structure design

There are a number of exceptional examples indicating the unique position of tetrahedral symmetry in the vast landscape of different spatial organization pathways which can be sampled by matter. This work shows that the design and analysis of relatively simple tetrahedron clusters can lead to the formulation of a new type of dendritic structure together with unique periodic frameworks resembling clathrates and foams. A simple sequential protocol leading from regular tetrahedron clusters to more complex structural motifs can be employed to determine interesting repetitive building units. Accordingly, four different hierarchical superstructures are introduced, in which the dominant population of nodes is based on tetrahedral symmetry. The introduced architectures could be of particular interest for the field of regenerative medicine and metamaterial engineering.

Hybrids of manganese oxide and lipid liquid crystalline nanoparticles (LLCNPs@MnO) as potential magnetic resonance imaging (MRI) contrast agents

Due to the health risks associated with the use of Gd-chelates and the promising effects of using nanoparticles as T1 contrast agents (CAs) for MRI, Mn-based nanoparticles are considered a highly competitive alternative. The use of hybrid constructs with paramagnetic functionality of Mn-based nanoparticles is an effective approach, in particular, the use of biocompatible lipid liquid crystalline nanoparticles (LLCNPs) as a carrier of MnO nanoparticles. LLCNPs possess a unique internal structure ensuring a payload of different polarity MnO nanoparticles. In view of MRI application, the surface properties including the polarity of MnO are crucial factors determining their relaxation rate and thus the MRI efficiency. Two novel hybrid constructs consisting of LLCNPs loaded with hydrophobic MnO-oleate and hydrophilic MnO-DMSA NPs were prepared. These nanosystems were studied in terms of their physico-chemical properties, positive T1 contrast enhancement properties (in vitro and in vivo) and biological safety. LLCNPs@MnO-oleate and LLCNPs@MnO-DMSA hybrids exhibited a heterogeneous phase composition, however with differences in the inner periodic arrangement and structural parameters, as well as in the preferable localization of MnO NPs within the LLCNPs. Also, these hybrids differed in terms of particle size-related parameters and colloidal stability, which was found to be strongly dependent on the addition of differently functionalized MnO NPs. Embedding both types of MnO NPs into LLCNPs resulted in high relaxivity parameters, in comparison to bare MnO-DMSA NPs and also commercially developed CAs (e.g. Dotarem and Teslascan). Further biosafety studies revealed that cell internalization pathways were dependent on the prepared hybrid type, while viability, effects on the mitochondria membrane potential and cytoskeletal networks were rather related to the susceptibility of the particular cell line. The high relaxation rates achieved with the developed hybrid LLCNPs@MnO enable them to be possibly used as novel and biologically safe MRI T1-enhancing CAs in in vivo imaging.

Liquid crystalline nanoparticles enable a multifunctional approach for topical psoriasis therapy by co-delivering triptolide and siRNAs

Liquid crystalline nanoparticles (LCNs) are an attractive drugs topical delivery system due to the great internal ordering, wide interfacial area and structural similarities with the skin. In this work, LCNs were designed to encapsulate triptolide (TP) and to complex on its surface small interfering RNAs (siRNA) targeting TNF-α and IL-6, aiming at topical co-delivery and regulating multi-targets in psoriasis. These multifunctional LCNs showed appropriate physicochemical properties for topical application, such as a mean size of 150 nm, low polydispersion, TP encapsulation greater than 90% and efficient complexation with siRNA. The internal reverse hexagonal mesostructure of LCNs was confirmed by SAXS while their morphology was assessed by cryo-TEM. In vitro permeation studies revealed an increase of more than 20-fold in the distribution of TP through the porcine epidermis/dermis was achieved after the application of LCN-TP or LCN TP in hydrogel. In cell culture, LCNs showed good compatibility and rapid internalization, which was attributed to macropinocytosis and caveolin-mediated endocytosis. Anti-inflammatory potential of multifunctional LCNs was assessed by reducing of TNF-α, IL-6, IL-1β and TGF-β1 levels in LPS-stimulated macrophages. These results support the hypothesis that the co-delivery of TP and siRNAs by LCNs may be a new strategy for psoriasis topical therapy.

Bringing lipidic lyotropic liquid crystal technology into biomedicine

Liquid crystals (LCs), discovered more than 130 years ago, are now emerging in the field of biomedicine. This article highlights the recent uses of lipid lyotropic LCs in therapeutics delivery, imaging, and tissue engineering and invites the scientific community to continue exploring the design of more complex LCs.

Lyotropic liquid crystals for parenteral drug delivery

The necessity for long-term treatments of chronic diseases has encouraged the development of novel long-acting parenteral formulations intending to improve drug pharmacokinetics and therapeutic efficacy. Lately, one of the novel approaches has been developed based on lipid-based liquid crystals. The lyotropic liquid crystal (LLC) systems consist of amphiphilic molecules and are formed in presence of solvents with the most common types being cubic, hexagonal and lamellar mesophases. LC injectables have been recently developed based on polar lipids that spontaneously form liquid crystal nanoparticles in aqueous tissue environments to create the in-situ long-acting sustained-release depot to provide treatment efficacy over extended periods. In this manuscript, we have consolidated and summarized the various type of liquid crystals, recent formulation advancements, analytical evaluation, and therapeutic application of lyotropic liquid crystals in the field of parenteral sustained release drug delivery.