Novel methods for liposome preparation

What We Need to Know about Liposomes as Drug Nanocarriers: An Updated Review

Liposomes have been attracted considerable attention as phospholipid spherical vesicles, over the past 40 years. These lipid vesicles are valued in biomedical application due to their ability to carry both hydrophobic and hydrophilic agents, high biocompatibility and biodegradability. Various methods have been used for the synthesis of liposomes, so far and numerous modifications have been performed to introduce liposomes with different characteristics like surface charge, size, number of their layers, and length of circulation in biological fluids. This article provides an overview of the significant advances in synthesis of liposomes via active or passive drug loading methods, as well as describes some strategies developed to fabricate their targeted formulations to overcome limitations of the "first-generation" liposomes.

Comparison of different types of liposomal nano structures for microRNA transfection to human mesenchymal stem cell line S1939

Background: Liposomes are utilized as a drug delivery carrier in various fields of biomedicine. They are synthesized in the nanometer-size range and are becoming a viable drug delivery carrier for the treatment of different diseases. MicroRNAs as regulatory elements could be transferred to cells for changing their morphology or physiology. The study's major aim is to find the optimized formula of liposomes for transfection of microRNA to human mesenchymal stem cell line S1939 (HMSCs). Materials and Methods: Various ratios of soybean phosphatidylcholine (SPC), cholesterol, 1, 2 dioleoyloxy-3- (trimethylammonium) propane (DOTAP), and polyethylene glycol (PEG) were combined. The mean diameter of all formulations and their surface properties were determined by a zeta sizer device and scanning electron microscope, respectively. The cytotoxicity of formulations was assessed using MTT (3,4,5-dimethyl thiazol-2-yl) (2,5-diphenyltetrazolium bromide) assay. The transfection effectiveness of liposomal miRNA vs empty liposomes was determined using agarose gel electrophoresis. Results: The optimized liposome vesicles were prepared using 45:30:27.5:5 molar ratios of SPC:DOTAP:cholesterol: DSPE-PEG. The liposome formulations F10 and F18 were the best in terms of biocompatibility because of the higher viabilities of treated cells. The best formulation (F18, containing 0.7 µg of miRNA and 10 µg of liposome) was nearly 100% efficient in sequestering and fixing miRNA. Phase-contrast and fluorescent microscopic examinations showed intra-nuclear as well as intracytoplasmic localization of the particles. Conclusion: Some easily prepared liposomal formulation vehicles are quite efficient in the transfection of miRNA into the HMSCs and could be used for in vitro applications in regenerative medicine.

Encapsulation of Vitamins Using Nanoliposome: Recent Advances and Perspectives

Nowadays the importance of vitamins is clear for everyone. However, many patients are suffering from insufficient intake of vitamins. Incomplete intake of different vitamins from food sources due to their destruction during food processing or decrease in their bioavailability when mixing with other food materials, are factors resulting in vitamin deficiency in the body. Therefore, various lipid based nanocarriers such as nanoliposomes were developed to increase the bioavailability of bioactive compounds. Since the function of nanoliposomes containing vitamins on the body has a direct relationship with the quality of produced nanoliposomes, this review study was planned to investigate the several aspects of liposomal characteristics such as size, polydispersity index, zeta potential, and encapsulation efficiency on the quality of synthesized vitamin-loaded nanoliposomes.

Nanoliposome based biosensors for probing mycotoxins and their applications for food: A review

Mycotoxins are the most common feed and food contaminants affecting animals and humans, respectively; continuous exposure causes tremendous health problems such as kidney disorders, infertility, immune suppression, liver inflammation, and cancer. Consequently, their control and quantification in food materials is crucial. Biosensors are potential tools for the rapid detection and quantification of mycotoxins with high sensitivity and selectivity. Nanoliposomes (NLs) are vesicular carriers formed by self-assembling phospholipids that surround the aqueous cores. Utilizing their biocompatibility, biodegradability, and high carrying capacity, researchers have employed NLs in biosensors for monitoring various targets in biological and food samples. The NLs are used for surface modification, signal marker delivery, and detection of toxins, bacteria, pesticides, and diseases. Here, we review marker-entrapped NLs used in the development of NL-based biosensors for mycotoxins. These biosensors are sensitive, selective, portable, and cost-effective analytical tools, and the resulting signal can be produced and/or amplified with or without destroying the NLs. In addition, this review emphasizes the benefits of the immunoliposome method in comparison with traditional detection approaches. We expect this review to serve as a valuable reference for researchers in this rapidly growing field. The insights provided may facilitate the rational design of next-generation NL-based biosensors.

Biomimetic asymmetric bacterial membranes incorporating lipopolysaccharides

Gram-negative bacteria are equipped with a cell wall that contains a complex matrix of lipids, proteins, and glycans, which form a rigid layer protecting bacteria from the environment. Major components of this outer membrane are the high-molecular weight and amphiphilic lipopolysaccharides (LPSs). They form the extracellular part of a heterobilayer with phospholipids. Understanding LPS properties within the outer membrane is therefore important to develop new antimicrobial strategies. Model systems, such as giant unilamellar vesicles (GUVs), provide a suitable platform for exploring membrane properties and interactions. However, LPS molecules contain large polysaccharide parts that confer high water solubility, which makes LPS incorporation in artificial membranes difficult; this hindrance is exacerbated for LPS with long polysaccharide chains, i.e., the smooth LPS. Here, a novel emulsification step of the inverted emulsion method is introduced to incorporate LPS in the outer or the inner leaflet of GUVs, exclusively. We developed an approach to determine the LPS content on individual GUVs and quantify membrane asymmetry. The asymmetric membranes with outer leaflet LPS show incorporations of 1-16 mol % smooth LPS (corresponding to 16-79 wt %), while vesicles with inner leaflet LPS reach coverages of 2-7 mol % smooth LPS (28-60 wt %). Diffusion coefficient measurements in the obtained GUVs showed that increasing LPS concentrations in the membranes resulted in decreased diffusivity.

Nanotechnology for colorectal cancer detection and treatment

Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.

Hydroxyethylcellulose-Based Hydrogels Containing Liposomes Functionalized with Cell-Penetrating Peptides for Nasal Delivery of Insulin in the Treatment of Diabetes

Liposomes functionalized with cell-penetrating peptides are a promising strategy to deliver insulin through the nasal route. A hydrogel based on hydroxyethylcellulose (HEC) aqueous solution was prepared, followed by a subsequent addition of liposomes containing insulin solution functionalized with trans-activator of transcription protein of HIV-1 (TAT) or Penetratin (PNT). The formulations were characterized for rheological behavior, mucoadhesion, syringeability, in vitro release and in vivo efficacy. Rheological tests revealed non-Newtonian fluids with pseudoplastic behavior, and the incorporation of liposomes (HLI, HLI_TAT and HLI_PNT) in hydrogels did not alter the behavior original pseudoplastic characteristic of the HEC hydrogel. Pseudoplastic flow behavior is a desirable property for formulations intended for the administration of drugs via the nasal route. The results of syringeability and mucoadhesive strength from HEC hydrogels suggest a viable vehicle for nasal delivery. Comparing the insulin release profile, it is observed that HI was the system that released the greatest amount while the liposomal gel promoted greater drug retention, since the liposomal system provides an extra barrier for the release through the hydrogel. Additionally, it is observed that both peptides tested had an impact on the insulin release profile, promoting a slower release, due to complexation with insulin. The in vitro release kinetics of insulin from all formulations followed Weibull's mathematical model, reaching approximately 90% of release in the formulation prepared with HEC-based hydrogels. Serum insulin levels and the antihyperglycemic effects suggested that formulations HI and HLI have potential as carriers for insulin delivery by the nasal pathway, a profile not observed when insulin was administered by subcutaneous injection or by the nasal route in saline. Furthermore, formulations functionalized with TAT and PNT can be considered promoters of late and early absorption, respectively.

Microfluidic vortex focusing for high throughput synthesis of size-tunable liposomes

Control over vesicle size during nanoscale liposome synthesis is critical for defining the pharmaceutical properties of liposomal nanomedicines. Microfluidic technologies capable of size-tunable liposome generation have been widely explored, but scaling these microfluidic platforms for high production throughput without sacrificing size control has proven challenging. Here we describe a microfluidic-enabled process in which highly vortical flow is established around an axisymmetric stream of solvated lipids, simultaneously focusing the lipids while inducing rapid convective and diffusive mixing through application of the vortical flow field. By adjusting the individual buffer and lipid flow rates within the system, the microfluidic vortex focusing technique is capable of generating liposomes with precisely controlled size and low size variance, and may be operated up to the laminar flow limit for high throughput vesicle production. The reliable formation of liposomes as small as 27 nm and mass production rates over 20 g/h is demonstrated, offering a path toward production-scale liposome synthesis using a single continuous-flow vortex focusing device.

Liposomes and liposome-like nanoparticles: From anti-fungal infection to the COVID-19 pandemic treatment

The liposome is the first nanomedicine transformed into the market and applied to human patients. Since then, such phospholipid bilayer vesicles have undergone technological advancements in delivering small molecular-weight compounds and biological drugs. Numerous investigations about liposome uses were conducted in different treatment fields, including anti-tumor, anti-fungal, anti-bacterial, and clinical analgesia, owing to liposome's ability to reduce drug cytotoxicity and improve the therapeutic efficacy and combinatorial delivery. In particular, two liposomal vaccines were approved in 2021 to combat COVID-19. Herein, the clinically used liposomes are reviewed by introducing various liposomal preparations in detail that are currently proceeding in the clinic or on the market. Finally, we discuss the challenges of developing liposomes and cutting-edge liposomal delivery for biological drugs and combination therapy.

Liposomal formulations for treating lysosomal storage disorders

Lysosomal storage disorders (LSD) are a group of rare life-threatening diseases caused by a lysosomal dysfunction, usually due to the lack of a single enzyme required for the metabolism of macromolecules, which leads to a lysosomal accumulation of specific substrates, resulting in severe disease manifestations and early death. There is currently no definitive cure for LSD, and despite the approval of certain therapies, their effectiveness is limited. Therefore, an appropriate nanocarrier could help improve the efficacy of some of these therapies. Liposomes show excellent properties as drug carriers, because they can entrap active therapeutic compounds offering protection, biocompatibility, and selectivity. Here, we discuss the potential of liposomes for LSD treatment and conduct a detailed analysis of promising liposomal formulations still in the preclinical development stage from various perspectives, including treatment strategy, manufacturing, characterization, and future directions for implementing liposomal formulations for LSD.

Liposomes as Delivery System for Applications in Meat Products

In the meat industry, microbial contamination, and lipid and protein oxidation are important factors for quality deterioration. Although natural preservatives have been widely used in various meat products, their biological activities are often reduced due to their volatility, instability, and easy degradation. Liposomes as an amphiphilic delivery system can be used to encapsulate food active compounds, which can improve their stability, promote antibacterial and antioxidant effects and further extend the shelf life of meat products. In this review, we mainly introduce liposomes and methods of their preparation including conventional and advanced techniques. Meanwhile, the main current applications of liposomes and biopolymer-liposome hybrid systems in meat preservation are presented.

A new core–shell-type nanoparticle loaded with paclitaxel/norcantharidin and modified with APRPG enhances anti-tumor effects in hepatocellular carcinoma

Nanoparticle delivery systems have been shown to improve the therapeutic efficacy of anti-cancer drugs, including a variety of drugs for the treatment of hepatocellular carcinoma (HCC). However, the current systems show some limitations, and the delivery of more effective nanoparticle systems for anti-HCC drugs with better targeting ability are needed. Here, we created paclitaxel (PTX)/norcantharidin (NCTD)-loaded core–shell lipid nanoparticles modified with a tumor neovasculature-targeted peptide (Ala-Pro-Arg-Pro-Gly, APRPG) and investigated their anti-tumor effects in HCC. Core–shell-type lipid nanoparticles (PTX/NCTD-APRPG-NPs) were established by combining poly(lactic-co-glycolic acid) (PLGA)-wrapped PTX with phospholipid-wrapped NCTD, followed by modification with APRPG. For comparison, PTX-loaded PLGA nanoparticles (PTX-NPs) and PTX/NCTD-loaded core–shell-type nanoparticles without APRPG (PTX/NCTD-NPs) were prepared. The in vitro and in vivo anti-tumor effects were examined in HepG2 cells and tumor-bearing mice, respectively. Morphological and release characterization showed that PTX/NCTD-APRPG-NPs were prepared successfully and achieved up to 90% release of PTX in a sustained manner. Compared with PTX/NCTD-NPs, PTX/NCTD-APRPG-NPs significantly enhanced the uptake of PTX. Notably, the inhibition of proliferation and migration of hepatoma cells was significantly higher in the PTX/NCTD-APRPG-NP group than those in the PTX-NP and PTX/NCTD-NP groups, which reflected significantly greater anti-tumor properties as well. Furthermore, key molecules in cell proliferation and apoptosis signaling pathways were altered most in the PTX/NCTD-APRPG-NP group, compared with the PTX-NP and PTX/NCTD-NP groups. Collectively, PTX/NCTD-loaded core–shell lipid nanoparticles modified with APRPG enhance the effectiveness of anti-HCC drugs and may be an effective system for the delivery of anti-HCC drugs.

CRISPR/nCas9-Based Genome Editing on GM2 Gangliosidoses Fibroblasts via Non-Viral Vectors

The gangliosidoses GM2 are a group of pathologies mainly affecting the central nervous system due to the impaired GM2 ganglioside degradation inside the lysosome. Under physiological conditions, GM2 ganglioside is catabolized by the β-hexosaminidase A in a GM2 activator protein-dependent mechanism. In contrast, uncharged substrates such as globosides and some glycosaminoglycans can be hydrolyzed by the β-hexosaminidase B. Monogenic mutations on HEXA, HEXB, or GM2A genes arise in the Tay–Sachs (TSD), Sandhoff (SD), and AB variant diseases, respectively. In this work, we validated a CRISPR/Cas9-based gene editing strategy that relies on a Cas9 nickase (nCas9) as a potential approach for treating GM2 gangliosidoses using in vitro models for TSD and SD. The nCas9 contains a mutation in the catalytic RuvC domain but maintains the active HNH domain, which reduces potential off-target effects. Liposomes (LPs)- and novel magnetoliposomes (MLPs)-based vectors were used to deliver the CRISPR/nCas9 system. When LPs were used as a vector, positive outcomes were observed for the β-hexosaminidase activity, glycosaminoglycans levels, lysosome mass, and oxidative stress. In the case of MLPs, a high cytocompatibility and transfection ratio was observed, with a slight increase in the β-hexosaminidase activity and significant oxidative stress recovery in both TSD and SD cells. These results show the remarkable potential of CRISPR/nCas9 as a new alternative for treating GM2 gangliosidoses, as well as the superior performance of non-viral vectors in enhancing the potency of this therapeutic approach.

Nucleic acid-based supramolecular structures: vesicular spherical nucleic acids from a non-phospholipid nucleolipid

Vesicular spherical nucleic acids are dynamic nucleic acid-based supramolecular structures that are held together via non-covalent bonds. They have promising applications as drug and nucleic acid delivery materials, diagnostic and imaging tools and platforms for development of various therapeutic schemes. In this contribution, we report on vesicular spherical nucleic acids, constructed from a non-phospholipid nucleolipid - an original hybrid biomacromolecule, composed of a hydrophobic residue, resembling that of the naturally occurring phospholipids, and a DNA oligonucleotide strand. The nucleolipid was synthesized by coupling of dibenzocyclooctyne-functionalized oligonucleotide and azidated 1,3-dihexadecyloxy-propane-2-ol via an azide-alkyne click reaction. In aqueous solution it spontaneously self-associated into nanosized supramolecular structures, identified as unilamellar vesicles composed of a self-closed interdigitated bilayer. Vesicular structures were also formed upon intercalation of the nucleolipid via its lipid-mimetic residue in the phospholipid bilayer membrane of liposomes prepared from readily available and FDA-approved lipids (1,2-dipalmitoyl-rac-glycero-3-phosphocholine and cholesterol). The vesicular structures are thoroughly investigated by light scattering (dynamic, static, and electrophoretic) and cryogenic TEM and the physical characteristics, in particular, number of strands per particle, grafting density, and conformation of the strands, were compared to those of reference spherical nucleic acids. Finally, the vesicular structures were shown to exhibit cellular internalization with no need of transfection agents and enhanced colloidal and nuclease stability.

Delivery and assessment of a CRISPR/nCas9-based genome editing system on in vitro models of mucopolysaccharidoses IVA assisted by magnetite-based nanoparticles

Mucopolysaccharidosis IV A (MPS IVA) is a lysosomal disorder caused by mutations in the GALNS gene. Consequently, the glycosaminoglycans (GAGs) keratan sulfate and chondroitin 6-sulfate accumulate in the lysosomal lumen. Although enzyme replacement therapy has shown essential advantages for the patients, several challenges remain to overcome, such as the limited impact on the bone lesion and recovery of oxidative profile. Recently, we validated a CRISPR/nCas9-based gene therapy with promising results in an in vitro MPS IVA model. In this study, we have expanded the use of this CRISPR/nCas9 system to several MPS IVA fibroblasts carrying different GALNS mutations. Considering the latent need to develop more safety vectors for gene therapy, we co-delivered the CRISPR/nCas9 system with a novel non-viral vector based on magnetoliposomes (MLPs). We found that the CRISPR/nCas9 treatment led to an increase in enzyme activity between 5 and 88% of wild-type levels, as well as a reduction in GAGs accumulation, lysosomal mass, and mitochondrial-dependent oxidative stress, in a mutation-dependent manner. Noteworthy, MLPs allowed to obtain similar results to those observed with the conventional transfection agent lipofectamine. Overall, these results confirmed the potential of CRISPR/nCas9 as a genome editing tool for treating MPS IVA. We also demonstrated the potential use of MLPs as a novel delivery system for CRISPR/nCas9-based therapies.

Lipid-Based Drug Delivery Systems for Diseases Managements

Liposomes are tiny lipid-based vesicles composed of one or more lipid bilayers, which facilitate the encapsulation of hydrophilic, lipophilic, and amphiphilic biological active agents. The description of the physicochemical properties, formulation methods, characteristics, mechanisms of action, and large-scale manufacturing of liposomes as delivery systems are deeply discussed. The benefits, toxicity, and limitations of the use of liposomes in pharmacotherapeutics including in diagnostics, brain targeting, eye and cancer diseases, and in infections are provided. The experimental approaches that may reduce, or even bypass, the use of liposomal drug drawbacks is described. The application of liposomes in the treatment of numerous diseases is discussed.

Recent advances in superlubricity of liposomes for biomedical applications

Achieving superlubricity, a state of lubrication where friction nearly vanishes, has become one of the most promising approaches to combat friction-induced energy dissipation and medical device failure. Phospholipids are amphiphilic molecules comprising highly hydrophilic phosphatidylcholine head groups as well as hydrophobic hydrocarbon chains, When solubilized, phospholipids can readily self-assemble to form different structures such as bilayers and vesicles (liposomes). Recently, liposomes have been identified as excellent lubricants, especially in the boundary lubrication regime the most common lubrication status in the field of biotribology. In this review, we summarize recent progress in employing liposomes as key players for employing superlubricity in biomedical applications. The relationship between lipids and liposomes, manufacturing approaches, lubrication regimes, and regulation mechanisms of liposomes are discussed. Finally, we indicate possible future directions for the use of liposome-mediated superlubricity in biomedical applications.

Frame-Guided Assembly of Amphiphiles

ConspectusAmphiphiles tend to self-assemble into various structures and morphologies in aqueous environments (e.g., micelles, tubes, fibers, vesicles, and lamellae). These assemblies and their properties have made significant impact in traditional chemical industries, e.g., increasing solubility, decreasing surface tension, facilitating foaming, etc. It is well-known that the molecular structure and its environment play a critical role in the assembly process, and many theories, including critical packing factor, thermodynamic models, etc., have been proposed to explain and predict the assembly morphology. It has been recognized that the morphology of the amphiphilic assembly plays important roles in determining the functions, such as curvature-dependent biophysical (e.g., liposome fusion and fission) and biochemical (e.g., lipid metabolism and membrane protein trafficking) processes, size-related EPR (enhanced permeability and retention) effects, etc. Meanwhile, various nanomaterials have promised great potential in directing the arrangement of molecules, thus generating unique functions. Therefore, control over the amphiphilic morphology is of great interest to scientists, especially in nanoscale with the assistance of functional nanomaterials. However, how to precisely manipulate the sizes and shapes of the assemblies is challenged by the entropic nature of the hydrophobic interaction. Inspired by the "cytoskeleton-membrane protein-lipid bilayer" principle of the cell membrane, a strategy termed "frame-guided assembly (FGA)" has been proposed and developed to direct the arrangement of amphiphiles. The FGA strategy welcomes various nanomaterials with precisely controlled properties to serve as scaffolds. By introducing scattered hydrophobic molecules, which are defined as either leading hydrophobic groups (LHGs) or nucleation seeds onto a selected scaffold, a discontinuous hydrophobic trace along the scaffold can be outlined, which will further guide the amphiphiles in the system to grow and form customized two- or three-dimensional (2D/3D) membrane geometries.Topologically, the supporting frame can be classified as three types including inner-frame, outer-frame, and planar-frame. Each type of FGA assembly possesses particular advantages: (1) The inner-frame, similar to endoskeletons of many cellular structures, steadily supports the membrane from the inside and exposes the full surface area outside. (2) The outer-frame, on the other hand, molds and constrains the membrane-wrapped vesicles to regulate their size and shape. It also allows postengineering of the frame to precisely decorate and dynamically manipulate the membrane. (3) The planar-frame mediates the growth of the 2D membrane that profits from the scanning-probe microscopic characterization and benefits the investigation of membrane proteins.In this Account, we introduce the recent progress of frame-guided assembly strategy in the preparation of customized amphiphile assemblies, evaluate their achievements and limitations, and discuss prospective developments and applications. The basic principle of FGA is discussed, and the morphology controllability is summarized in the inner-, outer-, and planar-frame categories. As a versatile strategy, FGA is able to guide different types of amphiphiles by designing specific LHGs for given molecular structures. The mechanism of FGA is then discussed systematically, including the driving force of the assembly, density and distribution of the LHGs, amphiphile concentration, and the kinetic process. Furthermore, the applications of FGA have been developed for liposome engineering, membrane protein incorporation, and drug delivery, which suggest the huge potential of FGA in fabricating novel and functional complexes.

Triggered and controlled release of bioactives in food applications

Bioactive compounds (e.g., nutraceuticals, micronutrients, antimicrobial, antioxidant) are added to food products and formulations to enhance sensorial/nutritional attributes and/or shelf-life. Many of these bioactives are susceptible to degradation when exposed to environmental and processing factors. Others involve in undesirable interactions with food constituents. Encapsulation is a useful tool for addressing these issues through various stabilization mechanisms. Besides protection, another important requirement of encapsulation is to design a carrier that predictably releases the encapsulated bioactive at the target site to elicit its intended functionality. To this end, controlled release carrier systems derived from interactive materials have been developed and commercially exploited to meet the requirements of various applications. This chapter provides an overview on basic controlled and triggered release concepts relevant to food and active packaging applications. Different approaches to encapsulate bioactive compounds and their mode of release are presented, from simple blending with a compatible matrix to complex multiphase carrier systems. To further elucidate the mass transport processes, selected diffusion and empirical release kinetic models are presented, along with their brief historical significance. Finally, interactive carriers that are responsive to moisture, pH, thermal and chemical stimuli are presented to illustrate how these triggered release mechanisms can be useful for food applications.

Fabrication of Doxorubicin-Loaded Lipid-Based Nanocarriers by Microfluidic Rapid Mixing

Doxorubicin (Dox) is a widely known chemotherapeutic drug that has been encapsulated into liposomes for clinical use, such as Doxil® and Myocet®. Both of these are prepared via remote loading methods, which require multistep procedures. Additionally, their antitumor efficacy is hindered due to the poor drug release from PEGylated liposomes in the tumor microenvironment. In this study, we aimed to develop doxorubicin-loaded lipid-based nanocarriers (LNC-Dox) based on electrostatic interaction using microfluidic technology. The resulting LNC-Dox showed high loading capacity, with a drug-to-lipid ratio (D/L ratio) greater than 0.2, and high efficacy of drug release in an acidic environment. Different lipid compositions were selected based on critical packing parameters and further studied to outline their effects on the physicochemical characteristics of LNC-Dox. Design of experiments was implemented for formulation optimization. The optimized LNC-Dox showed preferred release in acidic environments and better therapeutic efficacy compared to PEGylated liposomal Dox in vivo. Thus, this study provides a feasible approach to efficiently encapsulate doxorubicin into lipid-based nanocarriers fabricated by microfluidic rapid mixing.

Aqueous Heat Method for the Preparation of Hybrid Lipid–Polymer Structures: From Preformulation Studies to Protein Delivery

Liposomes with adjuvant properties are utilized to carry biomolecules, such as proteins, that are often sensitive to the stressful conditions of liposomal preparation processes. The aim of the present study is to use the aqueous heat method for the preparation of polymer-grafted hybrid liposomes without any additional technique for size reduction. Towards this scope, liposomes were prepared through the combination of two different lipids with adjuvant properties, namely dimethyldioctadecylammonium (DDA) and D-(+)-trehalose 6,6′-dibehenate (TDB) and the amphiphilic block copolymer poly(2-(dimethylamino)ethyl methacrylate)-b-poly(lauryl methacrylate) (PLMA-b-PDMAEMA). For comparison purposes, PAMAM dendrimer generation 4 (PAMAM G4) was also used. Preformulation studies were carried out by differential scanning calorimetry (DSC). The physicochemical characteristics of the prepared hybrid liposomes were evaluated by light scattering and their morphology was evaluated by cryo-TEM. Subsequently, in vitro nanotoxicity studies were performed. Protein-loading studies with bovine serum albumin were carried out to evaluate their encapsulation efficiency. According to the results, PDMAEMA-b-PLMA was successfully incorporated in the lipid bilayer, providing improved physicochemical and morphological characteristics and the ability to carry higher cargos of protein, compared to pure DDA:TDB liposomes, without affecting the biocompatibility profile. In conclusion, the aqueous heat method can be applied in polymer-grafted hybrid liposomes for protein delivery without further size-reduction processes.

Nanoparticles Loaded with Docetaxel and Resveratrol as an Advanced Tool for Cancer Therapy

A growing interest in the use of a combination of chemosensitizers and cytostatics for overcoming cancer resistance to treatment and the development of their delivery systems has been observed. Resveratrol (Res) presents antioxidant, anti-inflammatory and chemopreventive properties but also limits multidrug resistance against docetaxel (Dtx), which is one of the main causes of failure in cancer therapy with this drug. However, the use of both drugs presents challenges, including poor bioavailability, the unfavourable pharmacokinetics and chemical instability of Res and the poor water solubility and dose-limiting toxicity of Dtx. In order to overcome these difficulties, attempts have been made to create different forms of delivery for both agents. This review is focused on the latest developments in nanoparticles for the delivery of Dtx, Res and for the combined delivery of those two drugs. The aim of this review was also to summarize the synergistic mechanism of action of Dtx and Res on cancer cells. According to recent reports, Dtx and Res loaded in a nano-delivery system exhibit better efficiency in cancer treatment compared to free drugs. Also, the co-delivery of Dtx and Res in one actively targeted delivery system providing the simultaneous release of both drugs in cancer cells has a chance to fulfil the requirements of effective anticancer therapy and reduce limitations in therapy caused by multidrug resistance (MDR).

Curcumin-Loaded Liposome Preparation in Ultrasound Environment under Pressurized Carbon Dioxide

Curcumin-loaded liposomes were prepared using a supercritical carbon dioxide (SCCO2)−ultrasound environment system. The experiments were performed at temperatures of 40−70 °C and pressures of 10−25 MPa in a batch system with ultrasonication for 60 min. Transmission electron microscopy (TEM) images revealed liposome products with spherical morphologies and diameters of <100 nm. Dynamic light scattering (DLS) analysis indicated that the curcumin-loaded liposome nanosuspension exhibited good stability. Changing the operating conditions influenced the amount of liposome-encapsulated curcumin; as the operating temperature or pressure increased, the diameter of the liposome products and the amount of liposome-encapsulated curcumin increased and decreased, respectively. Herein, we described an innovative and practical organic-solvent-free method for generating liposomes from phospholipids.

Protocells: Milestones and Recent Advances

The origin of life is still one of humankind's great mysteries. At the transition between nonliving and living matter, protocells, initially featureless aggregates of abiotic matter, gain the structure and functions necessary to fulfill the criteria of life. Research addressing protocells as a central element in this transition is diverse and increasingly interdisciplinary. The authors review current protocell concepts and research directions, address milestones, challenges and existing hypotheses in the context of conditions on the early Earth, and provide a concise overview of current protocell research methods.

Knee Osteoarthritis Therapy: Recent Advances in Intra-Articular Drug Delivery Systems

Drug delivery for osteoarthritis (OA) treatment is a continuous challenge because of their poor bioavailability and rapid clearance in joints. Intra-articular (IA) drug delivery is a common strategy and its therapeutic effects depend mainly on the efficacy of the drug-delivery system used for OA therapy. Different types of IA drug-delivery systems, such as microspheres, nanoparticles, and hydrogels, have been rapidly developed over the past decade to improve their therapeutic effects. With the continuous advancement in OA mechanism research, new drugs targeting specific cell/signaling pathways in OA are rapidly evolving and effective drug delivery is critical for treating OA. In this review, recent advances in various IA drug-delivery systems for OA treatment, OA targeted strategies, and related signaling pathways in OA treatment are summarized and analyzed based on current publications.

A Case Report of Subcutaneously Injected Liposomal Cannabidiol Formulation Used as a Compassion Therapy for Pain Management in a Dog

A 14-year-old intact mixed breed dog (26 kg) was submitted for a novel cannabidiol (CBD) analgesic treatment. The dog was cachectic and had a testicular neoplasia, hip and elbow osteoarthritis and severe cervical pain. Analgesic treatment included canine osteoarthritic supplement, robencoxib and gabapentin. An additional liposomal CBD injectable formulation at 5 mg/kg was administered subcutaneously between the shoulder blades. The dog was monitored using an activity monitoring collar (PetPace), owner wellbeing questionnaire (Canine Brief Pain Inventory; CBPI), pain interactive visual analog scale (iVAS), blood work and CBD plasma concentrations. A week from the injection and up to 3 weeks afterwards the dog had improved CBPI and iVAS pain scores, and increased collar activity scores. CBD was quantified in plasma for 28 days. Due to disease progression, further difficulty to rise and walk, and relapse to pain after 3 weeks, the owners requested a second liposomal CBD injection, which was performed 4 weeks following the first injection using 3 mg/kg dose. Two days later, the dog was found dead in the yard under direct sun, while environmental temperature was 37°C. Major findings on necropsy revealed evidence of heat stroke and severe cervical disc protrusion with spinal hematoma, none related to liposomal CBD. In conclusion, subcutaneous liposomal CBD produced quantifiable CBD plasma concentrations for 28 days and may be an effective additional treatment as part of multimodal pain management in dogs.

Liposomal Drug Delivery And Its Potential Impact On Cancer Research

Liposomes are one of the most versatile drug carriers due to their functional properties, such as higher biocompatibility, the ability to encapsulate hydrophilic and hydrophobic products, and higher biodegradability. Liposomes are a better and more significant nanocarrier for cancer therapy. The key to developing a better cancer-targeted nanocarrier is the development of targeted liposomes using various approaches. Several traditional and novel liposome preparation methods are briefly discussed in this mini-review. The current state of liposome targeting, active and passive liposome targeting in cancer therapy, ligand directed targeting (antibody, aptamer, and protein/peptide-mediated targeting), and other miscellaneous approaches such as stimuli-responsive liposome-based targeting, autophagy inhibition mediated targeting, and curcumin loaded liposomal targeting are all discussed within. All of this gathered and compiled information will shed new light on liposome targeting strategies in cancer treatment and will pique the interest of aspiring researchers and academicians.

Liposomal Nanoformulation as a Carrier for Curcumin and pEGCG—Study on Stability and Anticancer Potential

Nanoformulations are regarded as a promising tool to enable the efficient delivery of active pharmaceutical ingredients to the target site. One of the best-known and most studied nanoformulations are liposomes—spherical phospholipid bilayered nanocarriers resembling cell membranes. In order to assess the possible effect of a mixture of polyphenols on both the stability of the formulation and its biological activity, two compounds were embedded in the liposomes—(i) curcumin (CUR), (ii) a peracetylated derivative of (−)-epigallocatechin 3-O-gallate (pEGCG), and (iii) a combination of the aforementioned. The stability of the formulations was assessed in two different temperature ranges (4–8 and 20 °C) by monitoring both the particle size and their concentration. It was found that after 28 days of the experiment, the liposomes remained largely unchanged in terms of the particle size distribution, with the greatest change from 130 to 146 nm. The potential decomposition of the carried substances was evaluated using HPLC. The combined CUR and pEGCG was sensitive to temperature conditions; however its stability was greatly increased when compared to the solutions of the individual compounds alone—up to 9.67% of the initial concentration of pEGCG in liposomes after 28 days storage compared to complete decomposition within hours for the non-encapsulated sample. The potential of the prepared formulations was assessed in vitro on prostate (LNCaP) and bladder cancer (5637) cell lines, as well as on a non-cancerous human lung fibroblast cell line (MRC-5), with the highest activity of IC₅₀ equal 15.33 ± 2.03 µM for the mixture of compounds towards the 5637 cell line.

Vesicular Approach Review on Nanocarriers bearing Curcumin and Applications

Phytoconstituents have been used to treat a variety of human diseases for a long time, but their use in pharmaceuticals is limited because of their low aqueous solubility. Researchers have created vesicular systems to address many of the issues associated with the bioavailability and therapeutic efficacy of poorly water-soluble drugs and target the drug to the desired location in the body. Several vesicular nanocarrier systems have been developed. Review contrasts various vesicular drug delivery systems, including liposomes, sphingosomes, emulsomes, niosomes, ethosomes, virosomes, phytosomes, aquasomes, proniosomes, transfersomes, pharmacosomes. Vesicular drug delivery systems have caused a scientific revolution, which has resulted in the development of novel dosage forms. This review aims to illustrate the applications, advantages, and disadvantages of the vesicular approach as nanocarriers bearing curcumin and widely used in gene delivery, tumor-targeting to the brain, oral formulations, and resolving various problems associated with drug stability and permeability issues. Nanocarriers also has wide application as green nanocomposites and for antitubercular drugs depending on their physical properties.

Current Methods to Unravel the Functional Properties of Lysosomal Ion Channels and Transporters

A distinct set of channels and transporters regulates the ion fluxes across the lysosomal membrane. Malfunctioning of these transport proteins and the resulting ionic imbalance is involved in various human diseases, such as lysosomal storage disorders, cancer, as well as metabolic and neurodegenerative diseases. As a consequence, these proteins have stimulated strong interest for their suitability as possible drug targets. A detailed functional characterization of many lysosomal channels and transporters is lacking, mainly due to technical difficulties in applying the standard patch-clamp technique to these small intracellular compartments. In this review, we focus on current methods used to unravel the functional properties of lysosomal ion channels and transporters, stressing their advantages and disadvantages and evaluating their fields of applicability.

Nanosized paclitaxel-loaded niosomes: formulation, in vitro cytotoxicity, and apoptosis gene expression in breast cancer cell lines

BACKGROUND

In this study, the optimized niosomal formulation containing paclitaxel using non-ionic surfactants and cholesterol was designed and its cytotoxic effects against different breast cancer cell lines and apoptosis gene expression analysis were also investigated.

METHODS AND RESULTS

Due to enhancing equation variables, the Box-Behnken method has been applied. Lipid/drug molar ratio, the amounts of Span 60, and cholesterol were selected as the target for optimization. The particle size of niosome loaded paclitaxel and entrapment efficiency proportion have been considered in the role of dependent variables. Then the cytotoxic activity of the optimized formulation was evaluated using an MTT assay against different breast cancer cell lines including MCF-7, T-47D, SkBr3, and MDA-MB-231. The expression level of Bax and Bcl-2 apoptosis genes was determined by Real-Time PCR. In this study, the optimized niosomal formulation revealed that the synthesized niosomes had a spherical appearance and had an average size of 192.73 ± 5.50 nm so that the percentage of drug loading was 94.71 ± 1.56%. Moreover, this formulation showed a controlled and slowed release of paclitaxel at different pH (7.4, 6.5, and 5.4). The cytotoxicity results demonstrated that cell viability in all concentrations of niosome loaded paclitaxel had profound cytotoxic effects on all studied breast cancer cell lines compared to the free paclitaxel (p < 0.05). In addition, the expression of apoptosis genes was much higher than that of free paclitaxel indicating the susceptibility of cells to apoptosis.

CONCLUSIONS

As a result, niosomal formulations containing paclitaxel can be used as a new drug delivery system to increase cytotoxicity and treatment of breast cancer in the upcoming future.

Synthetic methods of lipid-coated mesoporous silica nanoparticles as drug carriers

The lipid-coated mesoporous silica nanoparticles (LMSNs) that can synergistically harness the advantages and mitigate the disadvantages of the liposomes and MSNs are considered potential drug carriers. So far, several methods have been developed to prepare LMSNs, including vesicle fusion, thin-film hydration, and solvent exchange. Despite their wide application in LMSN preparation, these methods are short of detailed elaboration and comparison, which hinders their further development. In this review, for the first time, the three methods are systematically summarized, including their mechanisms, influence factors, advantages, and limitations. Although these methods are all based on lipid self-assembly, there is still a difference between them. In order to efficiently prepare LMSNs, we proposed that a suitable method should be selected based on the actual situation. It is conceivable that the elaboration and comparison in this review will make these methods easy to be understood and provide guidance for the design of LMSNs as drug carriers.

coupled Hydrodynamic Flow Focusing (cHFF) to Engineer Lipid–Polymer Nanoparticles (LiPoNs) for Multimodal Imaging and Theranostic Applications

An optimal design of nanocarriers is required to overcome the gap between synthetic and biological identity, improving the clinical translation of nanomedicine. A new generation of hybrid vehicles based on lipid–polymer coupling, obtained by Microfluidics, is proposed and validated for theranostics and multimodal imaging applications. A coupled Hydrodynamic Flow Focusing (cHFF) is exploited to control the time scales of solvent exchange and the coupling of the polymer nanoprecipitation with the lipid self-assembly simultaneously, guiding the formation of Lipid–Polymer NPs (LiPoNs). This hybrid lipid–polymeric tool is made up of core–shell structure, where a polymeric chitosan core is enveloped in a lipid bilayer, capable of co-encapsulating simultaneously Gd-DTPA and Irinotecan/Atto 633 compounds. As a result, a monodisperse population of hybrid NPs with an average size of 77 nm, with preserved structural integrity in different environmental conditions and high biocompatibility, can be used for MRI and Optical applications. Furthermore, preliminary results show the enhanced delivery and therapeutic efficacy of Irinotecan-loaded hybrid formulation against U87 MG cancers cells.

Opportunities and Challenges for mRNA Delivery Nanoplatforms

With the global outbreak of SARS-CoV-2, mRNA vaccines became the first type of COVID-19 vaccines to enter clinical trials because of their facile production, low cost, and relative safety, which initiated great advances in mRNA therapeutic techniques. However, the development of mRNA therapeutic techniques still confronts some challenges. First, in vitro transcribed mRNA molecules can be easily degraded by ribonuclease (RNase), resulting in their low stability. Next, the negative charge of mRNA molecules prevents them from direct cell entry. Therefore, finding efficient and safe delivery technology could be the key issue to improve mRNA therapeutic techniques. In this Perspective, we mainly discuss the problems of the existing mRNA-based delivery nanoplatforms, including safety evaluation, administration routes, and preparation technology. Moreover, we also propose some views on strategies to further improve mRNA delivery technology.

SARS-CoV-2 treatment effects induced by ACE2-expressing microparticles are explained by the oxidized cholesterol-increased endosomal pH of alveolar macrophages

Exploring the cross-talk between the immune system and advanced biomaterials to treat SARS-CoV-2 infection is a promising strategy. Here, we show that ACE2-overexpressing A549 cell-derived microparticles (AO-MPs) are a potential therapeutic agent against SARS-CoV-2 infection. Intranasally administered AO-MPs dexterously navigate the anatomical and biological features of the lungs to enter the alveoli and are taken up by alveolar macrophages (AMs). Then, AO-MPs increase the endosomal pH but decrease the lysosomal pH in AMs, thus escorting bound SARS-CoV-2 from phago-endosomes to lysosomes for degradation. This pH regulation is attributable to oxidized cholesterol, which is enriched in AO-MPs and translocated to endosomal membranes, thus interfering with proton pumps and impairing endosomal acidification. In addition to promoting viral degradation, AO-MPs also inhibit the proinflammatory phenotype of AMs, leading to increased treatment efficacy in a SARS-CoV-2-infected mouse model without side effects. These findings highlight the potential use of AO-MPs to treat SARS-CoV-2-infected patients and showcase the feasibility of MP therapies for combatting emerging respiratory viruses in the future.

Microemulsion Based Nanostructures for Drug Delivery

Most of the active pharmaceutical compounds are often prone to display low bioavailability and biological degradation represents an important drawback. Due to the above, the development of a drug delivery system (DDS) that enables the introduction of a pharmaceutical compound through the body to achieve a therapeutic effect in a controlled manner is an expanding application. Henceforth, new strategies have been developed to control several parameters considered essential for enhancing delivery of drugs. Nanostructure synthesis by microemulsions (ME) consist of enclosing a substance within a wall material at the nanoscale level, allowing to control the size and surface area of the resulting particle. This nanotechnology has shown the importance on targeted drug delivery to improve their stability by protecting a bioactive compound from an adverse environment, enhanced bioavailability as well as controlled release. Thus, a lower dose administration could be achieved by minimizing systemic side effects and decreasing toxicity. This review will focus on describing the different biocompatible nanostructures synthesized by ME as controlled DDS for therapeutic purposes.

Aqueous broadband photopolymerization on microreactor arrays: from high throughput polymerization to fabricating artificial cells

Microreactor arrays combining ZnO and polyaniline are fabricated onto the bottom of multi-well plates to catalyze broadband sunlight-driven open-to-air polymerization in aqueous media.

Engineering pH-Sensitive Stable Nanovesicles for Delivery of MicroRNA Therapeutics

MicroRNAs (miRNAs) are small non-coding endogenous RNAs, which are attracting a growing interest as therapeutic molecules due to their central role in major diseases. However, the transformation of these biomolecules into drugs is limited due to their unstability in the bloodstream, caused by nucleases abundantly present in the blood, and poor capacity to enter cells. The conjugation of miRNAs to nanoparticles (NPs) could be an effective strategy for their clinical delivery. Herein, the engineering of non-liposomal lipid nanovesicles, named quatsomes (QS), for the delivery of miRNAs and other small RNAs into the cytosol of tumor cells, triggering a tumor-suppressive response is reported. The engineered pH-sensitive nanovesicles have controlled structure (unilamellar), size (<150 nm) and composition. These nanovesicles are colloidal stable (>24 weeks), and are prepared by a green, GMP compliant, and scalable one-step procedure, which are all unavoidable requirements for the arrival to the clinical practice of NP based miRNA therapeutics. Furthermore, QS protect miRNAs from RNAses and when injected intravenously, deliver them into liver, lung, and neuroblastoma xenografts tumors. These stable nanovesicles with tunable pH sensitiveness constitute an attractive platform for the efficient delivery of miRNAs and other small RNAs with therapeutic activity and their exploitation in the clinics.