A review on phospholipids and their main applications in drug delivery systems

Rapid Production of Nanoscale Liposomes Using a 3D-Printed Reactor-In-A-Centrifuge: Formulation, Characterisation, and Super-Resolution Imaging

Nanoscale liposomes have been extensively researched and employed clinically for the delivery of biologically active compounds, including chemotherapy drugs and vaccines, offering improved pharmacokinetic behaviour and therapeutic outcomes. Traditional laboratory-scale production methods often suffer from limited control over liposome properties (e.g., size and lamellarity) and rely on laborious multistep procedures, which may limit pre-clinical research developments and innovation in this area. The widespread adoption of alternative, more controllable microfluidic-based methods is often hindered by complexities and costs associated with device manufacturing and operation, as well as the short device lifetime and the relatively low liposome production rates in some cases. In this study, we demonstrated the production of liposomes comprising therapeutically relevant lipid formulations, using a cost-effective 3D-printed reactor-in-a-centrifuge (RIAC) device. By adjusting formulation- and production-related parameters, including the concentration of polyethylene glycol (PEG), temperature, centrifugation time and speed, and lipid concentration, the mean size of the produced liposomes could be tuned in the range of 140 to 200 nm. By combining selected experimental parameters, the method was capable of producing liposomes with a therapeutically relevant mean size of ~174 nm with narrow size distribution (polydispersity index, PDI ~0.1) at a production rate of >8 mg/min. The flow-through method proposed in this study has potential to become an effective and versatile laboratory-scale approach to simplify the synthesis of therapeutic liposomal formulations.

From Benznidazole to New Drugs: Nanotechnology Contribution in Chagas Disease

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Benznidazole and nifurtimox are the two approved drugs for their treatment, but both drugs present side effects and efficacy problems, especially in the chronic phase of this disease. Therefore, new molecules have been tested with promising results aiming for strategic targeting action against T. cruzi. Several studies involve in vitro screening, but a considerable number of in vivo studies describe drug bioavailability increment, drug stability, toxicity assessment, and mainly the efficacy of new drugs and formulations. In this context, new drug delivery systems, such as nanotechnology systems, have been developed for these purposes. Some nanocarriers are able to interact with the immune system of the vertebrate host, modulating the immune response to the elimination of pathogenic microorganisms. In this overview of nanotechnology-based delivery strategies for established and new antichagasic agents, different strategies, and limitations of a wide class of nanocarriers are explored, as new perspectives in the treatment and monitoring of Chagas disease.

Transferrin-Targeted Liposomes in Glioblastoma Therapy: A Review

Glioblastoma (GBM) is a highly aggressive brain tumor, and its treatment is further complicated by the high selectivity of the blood-brain barrier (BBB). The scientific community is urgently seeking innovative and effective therapeutic solutions. Liposomes are a promising new tool that has shown potential in addressing the limitations of chemotherapy, such as poor bioavailability and toxicity to healthy cells. However, passive targeting strategies based solely on the physicochemical properties of liposomes have proven ineffective due to a lack of tissue specificity. Accordingly, the upregulation of transferrin receptors (TfRs) in brain tissue has led to the development of TfR-targeted anticancer therapeutics. Currently, one of the most widely adopted methods for improving drug delivery in the treatment of GBM and other neurological disorders is the utilization of active targeting strategies that specifically target this receptor. In this review, we discuss the role of Tf-conjugated liposomes in GBM therapy and present some recent studies investigating the drug delivery efficiency of Tf-liposomes; in addition, we address some challenges currently facing this approach to treatment and present some potential improvement possibilities.

Uncovering the Lipid Web: Discovering the Multifaceted Roles of Lipids in Human Diseases and Therapeutic Opportunities

Lipids, characterized by their hydrophobic nature, encompass a wide range of molecules with distinct properties and functions [...].

Spontaneous Formation of Ultrasmall Unilamellar Vesicles in Mixtures of an Amphiphilic Drug and a Phospholipid

We have observed ultrasmall unilamellar vesicles, with diameters of less than 20 nm, in mixtures of the tricyclic antidepressant drug amitriptyline hydrochloride (AMT) and the unsaturated zwitterionic phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) in physiological saline solution. The size and shape of spontaneously formed self-assembled aggregates have been characterized using complementary techniques, i.e., small-angle neutron and X-ray scattering (SANS and SAXS) and cryo-transmission electron microscopy (cryo-TEM). We observe rodlike mixed micelles in more concentrated samples that grow considerably in length upon dilution, and a transition from micelles to vesicles is observed as the concentration approaches the critical micelle concentration of AMT. Unlike the micelles, the spontaneously formed vesicles decrease in size with each step of dilution, and ultrasmall unilamellar vesicles, with diameters as small as about 15 nm, were observed at the lowest concentrations. The spontaneously formed ultrasmall unilamellar vesicles maintain their size for as long we have investigated them (i.e., several months). To the best of our knowledge, such small vesicles have never before been reported to form spontaneously in a biocompatible phospholipid-based system. Most interestingly, the size of the vesicles was observed to be strongly dependent on the chemical structure of the phospholipid, and in mixtures of AMT and the phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), the vesicles were observed to be considerably larger in size. The self-assembly behavior in the phospholipid-drug surfactant system in many ways resembles the formation of equilibrium micelles and vesicles in mixed anionic/cationic surfactant systems.

Engineered Liposomes in Interventional Theranostics of Solid Tumors

Engineered liposomal nanoparticles have unique characteristics as cargo carriers in cancer care and therapeutics. Liposomal theranostics have shown significant progress in preclinical and clinical cancer models in the past few years. Liposomal hybrid systems have not only been approved by the FDA but have also reached the market level. Nanosized liposomes are clinically proven systems for delivering multiple therapeutic as well as imaging agents to the target sites in (i) cancer theranostics of solid tumors, (ii) image-guided therapeutics, and (iii) combination therapeutic applications. The choice of diagnostics and therapeutics can intervene in the theranostics property of the engineered system. However, integrating imaging and therapeutics probes within lipid self-assembly "liposome" may compromise their overall theranostics performance. On the other hand, liposomal systems suffer from their fragile nature, site-selective tumor targeting, specific biodistribution and premature leakage of loaded cargo molecules before reaching the target site. Various engineering approaches, viz., grafting, conjugation, encapsulations, etc., have been investigated to overcome the aforementioned issues. It has been studied that surface-engineered liposomes demonstrate better tumor selectivity and improved therapeutic activity and retention in cells/or solid tumors. It should be noted that several other parameters like reproducibility, stability, smooth circulation, toxicity of vital organs, patient compliance, etc. must be addressed before using liposomal theranostics agents in solid tumors or clinical models. Herein, we have reviewed the importance and challenges of liposomal medicines in targeted cancer theranostics with their preclinical and clinical progress and a translational overview.

Yield Enhancement of Valuable Lipid Compounds from Squid (Doryteuthis gahi) Waste by Ethanol/Acetone Extraction

The study focused on the extraction of valuable lipid compounds from squid (Doryteuthis gahi) waste by a low-toxicity solvent mixture (ethanol/acetone, 50:50, v/v). The effect of the waste weight/solvent volume (WW/SV, g·mL^-1) ratio and the number of extractions (NoE) on the total lipid (TL), phospholipid (PL), and tocopherol yields and on the fatty acid (FA) profile (eicosapentaenoic and docosahexaenoic acid contents; polyunsaturated FAs/saturated FAs and ω3/ω6 ratios) was investigated. As a result, an increased NoE led to an increased (p < 0.05) TL yield but a decreased (p < 0.05) proportion of PLs in the lipid extract. Additionally, a lower (p < 0.05) polyunsaturated FA/saturated FA ratio was detected by increasing the NoE. Some differences (p < 0.05) could be outlined as a result of increasing the WW/SV ratio; however, a definite trend for this extraction condition could not be concluded for any of the lipid parameters measured. Yield results were compared to those obtained by the conventional chloroform/methanol procedure. In order to attain an increased yield, the NoE required would depend on the polarity degree of the lipid molecule concerned. All ethanol/acetone extracting conditions tested led to remarkable yields for lipid compounds (PLs, α-tocopherol, ω3 FAs) and FA ratios with healthy, nutritional, and preserving properties.

Research Progress of Design Drugs and Composite Biomaterials in Bone Tissue Engineering

Bone, like most organs, has the ability to heal naturally and can be repaired slowly when it is slightly injured. However, in the case of bone defects caused by diseases or large shocks, surgical intervention and treatment of bone substitutes are needed, and drugs are actively matched to promote osteogenesis or prevent infection. Oral administration or injection for systemic therapy is a common way of administration in clinic, although it is not suitable for the long treatment cycle of bone tissue, and the drugs cannot exert the greatest effect or even produce toxic and side effects. In order to solve this problem, the structure or carrier simulating natural bone tissue is constructed to control the loading or release of the preparation with osteogenic potential, thus accelerating the repair of bone defect. Bioactive materials provide potential advantages for bone tissue regeneration, such as physical support, cell coverage and growth factors. In this review, we discuss the application of bone scaffolds with different structural characteristics made of polymers, ceramics and other composite materials in bone regeneration engineering and drug release, and look forward to its prospect.

The Evolution and Recent Trends in Acoustic Targeting of Encapsulated Drugs to Solid Tumors: Strategies beyond Sonoporation

Despite recent advancements in ultrasound-mediated drug delivery and the remarkable success observed in pre-clinical studies, no delivery platform utilizing ultrasound contrast agents has yet received FDA approval. The sonoporation effect was a game-changing discovery with a promising future in clinical settings. Various clinical trials are underway to assess sonoporation's efficacy in treating solid tumors; however, there are disagreements on its applicability to the broader population due to long-term safety issues. In this review, we first discuss how acoustic targeting of drugs gained importance in cancer pharmaceutics. Then, we discuss ultrasound-targeting strategies that have been less explored yet hold a promising future. We aim to shed light on recent innovations in ultrasound-based drug delivery including newer designs of ultrasound-sensitive particles specifically tailored for pharmaceutical usage.

Koelreuteria paniculata Seed Oil-A Rich Natural Source of Unsaturated Fatty Acids and Phytocompounds with DNA Protective Potential

The present work is focused on the physicochemical characteristics, chemical composition, and some biological activities of Koelreuteria paniculata seed oil. The glyceride oil, obtained with a Soxhlet apparatus by extraction with hexane, was characterized by a relatively high oil content (over 20%), and it is defined as a non-drying oil (iodine value-44 gI₂/100 g) with good oxidative stability (over 50 h). There were identified 11 fatty acids, 6 sterols, 3 tocopherols, and 6 phospholipids, as the last group was reported for the first time. The major components among them were-monounsaturated eicosenoic and oleic acids, β-sitosterol, β-tocopherol, and phosphatidylcholine. The in vitro tests demonstrated DNA protective activity and a lack of cytotoxicity of the oil, data that has been reported for the first time. The in vitro MTT test of the oil on HT-29 and PC3 cell lines did not indicate antitumor activity. The seed oil studied contains valuable bio-components, which have proven benefits for human health, and that is why it could be used in food, cosmetic, and pharmaceutical products.

Prospects and Challenges of Synergistic Effect of Fluorescent Carbon Dots, Liposomes and Nanoliposomes for Theragnostic Applications

The future of molecular-level therapy, efficient medical diagnosis, and drug delivery relies on the effective theragnostic function which can be achieved by the synergistic effect of fluorescent carbon dots (FCDs) liposomes (L) and nanoliposomes. FCDs act as the excipient navigation agent while liposomes play the role of the problem-solving agent, thus the term "theragnostic" would describe the effect of LFCDs properly. Liposomes and FCDs share some excellent at-tributes such as being nontoxic and biodegradable and they can represent a potent delivery system for pharmaceutical compounds. They enhance the therapeutic efficacy of drugs via stabilizing the encapsulated material by circumventing barriers to cellular and tissue uptake. These agents facilitate long-term drug biodistribution to the intended locations of action while eliminating systemic side effects. This manuscript reviews recent progress with liposomes, nanoliposomes (collectively known as lipid vesicles) and fluorescent carbon dots, by exploring their key characteristics, applications, characterization, performance, and challenges. An extensive and intensive understanding of the synergistic interaction between liposomes and FCDs sets out a new research pathway to an efficient and theragnostic / theranostic drug delivery and targeting diseases such as cancer.

High-pressure pulses for Aspergillus niger spore inactivation in a model pharmaceutical lipid emulsion

High hydrostatic pressure (HHP) is a non-thermal process widely used in the food industry to reduce microbial populations. However, rarely its effect has been assessed in products with high oil content. This study evaluated the efficacy of HHP (200, 250, and 300 MPa) at different temperatures (25, 35, and 45 °C) by cycles (1, 2, or 3) of 10 min in the inactivation of Aspergillus niger spores in a lipid emulsion. After treatments at 300 MPa for 1 cycle at 35 or 45 °C, no surviving spores were recovered. All treatments were modeled by the linear and Weibull models. The presence of shoulders and tails in the treatments at 300 MPa at 35 or 45 °C resulted in sigmoidal curves which cannot be described by the linear model, hence the Weibull + Tail, Shoulder + Log-lin + Tail, and double Weibull models were evaluated to elucidate the inactivation kinetics. The tailing formation could be related to the presence of resistance subpopulations. The double Weibull model showed better goodness of fit (RMSE <0.2) to describe the inactivation kinetics of the treatments with the higher spore reductions. HHP at 200-300 MPa and 25 °C did not reduce the Aspergillus niger spores. The combined HHP and mild temperatures (35-45 °C) favored fungal spore inactivation. Spore inactivation in lipid emulsions by HHP did not follow a linear inactivation. HHP at mild temperatures is an alternative to the thermal process in lipid emulsions.

A new approach to the development and assessment of doxorubicin-loaded nanoliposomes for the treatment of osteosarcoma in 2D and 3D cell culture systems

Doxorubicin (DOX) is an effective anticancer drug used for the treatment of osteosarcoma. Liposomal nanocarriers for doxorubicin administration are now regarded as one of the most promising approaches to overcome multiple drug resistance and adverse side effects. The use of hydrogel as a 3D scaffold to mimic the cellular environment and provide comparable biological conditions for deeper investigations of cellular processes has attracted considerable attention. This study aimed to evaluate the impact of liposomal doxorubicin on the osteosarcoma cell line in the presence of alginate hydrogel as a three-dimensional scaffold. Different liposomal formulations based on cholesterol, phospholipids, and surfactants containing doxorubicin were developed using the thin-layer hydration approach to improve therapeutic efficacy. The final selected formulation was superficially modified using DSPE-mPEG2000. A three-dimensional hydrogel culture model with appropriate structure and porosity was synthesized using sodium alginate and calcium chloride as crosslinks for hydrogel. Then, the physical properties of liposomal formulations, such as mechanical and porosity, were characterized. The toxicity of the synthesized hydrogel was also assessed. Afterward, the cytotoxicity of nanoliposomes was analyzed on the Saos-2 and HFF cell lines in the presence of a three-dimensional alginate scaffold using the MTT assay. The results indicated that the encapsulation efficiency, the amount of doxorubicin released within 8 h, the mean size of vesicles, and the surface charge were 82.2%, 33.0%, 86.8 nm, and -4.2 mv, respectively. As a result, the hydrogel scaffolds showed sufficient mechanical resistance and suitable porosity. The MTT assay demonstrated that the synthesized scaffold had no cytotoxicity against cells, while nanoliposomal DOX exhibited marked toxicity against the Saos-2 cell line in the 3D culture medium of alginate hydrogel compared to the free drug in the 2D culture medium. Our research showed that the 3D culture model physically resembles the cellular matrix, and nanoliposomal DOX with proper size could easily penetrate into cells and cause higher cytotoxicity compared to the 2D cell culture.

Development of Hybrid DSPC:DOPC:P(OEGMA950-DIPAEMA) Nanostructures: The Random Architecture of Polymeric Guest as a Key Design Parameter

Hybrid nanoparticles have gained a lot of attention due to their advantageous properties and versatility in pharmaceutical applications. In this perspective, the formation of novel systems and the exploration of their characteristics not only from a physicochemical but also from a biophysical perspective could promote the development of new nanoplatforms with well-defined features. In the current work, lipid/copolymer bilayers were formed in different lipid to copolymer ratios and examined via differential scanning calorimetry as a preformulation study to decipher the interactions between the biomaterials, followed by nanostructure preparation by the thin-film hydration method. Physicochemical and toxicological evaluations were conducted utilizing light scattering techniques, fluorescence spectroscopy, and MTS assay. 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) in different weight ratios were the chosen lipids, while a linear random copolymer with pH- and thermoresponsive properties comprised of oligo (ethylene glycol) methyl ether methacrylate (OEGMA) and 2-(diisopropylamino) ethyl methacrylate (DIPAEMA) in different ratios was used. According to our results, non-toxic hybrid nanosystems with stimuli-responsive properties were successfully formulated, and the main parameters influencing their overall performance were the hydrophilic/hydrophobic balance, lipid to polymer ratio, and more importantly the random copolymer topology. Hopefully, this investigation can promote a better understanding of the factors affecting the behavior of hybrid systems.

An Insight into Advances in Developing Nanotechnology Based Therapeutics, Drug Delivery, Diagnostics and Vaccines: Multidimensional Applications in Tuberculosis Disease Management

Tuberculosis (TB), one of the deadliest contagious diseases, is a major concern worldwide. Long-term treatment, a high pill burden, limited compliance, and strict administration schedules are all variables that contribute to the development of MDR and XDR tuberculosis patients. The rise of multidrug-resistant strains and a scarcity of anti-TB medications pose a threat to TB control in the future. As a result, a strong and effective system is required to overcome technological limitations and improve the efficacy of therapeutic medications, which is still a huge problem for pharmacological technology. Nanotechnology offers an interesting opportunity for accurate identification of mycobacterial strains and improved medication treatment possibilities for tuberculosis. Nano medicine in tuberculosis is an emerging research field that provides the possibility of efficient medication delivery using nanoparticles and a decrease in drug dosages and adverse effects to boost patient compliance with therapy and recovery. Due to their fascinating characteristics, this strategy is useful in overcoming the abnormalities associated with traditional therapy and leads to some optimization of the therapeutic impact. It also decreases the dosing frequency and eliminates the problem of low compliance. To develop modern diagnosis techniques, upgraded treatment, and possible prevention of tuberculosis, the nanoparticle-based tests have demonstrated considerable advances. The literature search was conducted using Scopus, PubMed, Google Scholar, and Elsevier databases only. This article examines the possibility of employing nanotechnology for TB diagnosis, nanotechnology-based medicine delivery systems, and prevention for the successful elimination of TB illnesses.

Formulation of Phytosomes with Extracts of Ginger Rhizomes and Rosehips with Improved Bioavailability, Antioxidant and Anti-Inflammatory Effects In Vivo

The poor water solubility of natural antioxidants restricts their bioavailability and therapeutic use. We aimed to develop a new phytosome formulation with active compounds from extracts of ginger (GINex) and rosehips (ROSAex) designed to increase their bioavailability, antioxidant and anti-inflammatory properties. The phytosomes (PHYTOGINROSA-PGR) were prepared from freeze-dried GINex, ROSAex and phosphatidylcholine (PC) in different mass ratios using the thin-layer hydration method. PGR was characterized for structure, size, zeta potential, and encapsulation efficiency. Results showed that PGR comprises several different populations of particles, their size increasing with ROSAex concentration, having a zeta potential of ~-21mV. The encapsulation efficiency of 6-gingerol and β-carotene was >80%. 31P NMR spectra showed that the shielding effect of the phosphorus atom in PC is proportional to the amount of ROSAex in PGR. PGR with a mass ratio GINex:ROSAex:PC-0.5:0.5:1 had the most effective antioxidant and anti-inflammatory effects in cultured human enterocytes. PGR-0.5:0.5:1 bioavailability and biodistribution were assessed in C57Bl/6J mice, and their antioxidant and anti-inflammatory effects were evaluated after administration by gavage to C57Bl/6J mice prior to LPS-induced systemic inflammation. Compared to extracts, PGR induced a 2.6-fold increase in 6-gingerol levels in plasma and over 40% in the liver and kidneys, in parallel with a 65% decrease in the stomach. PGR treatment of mice with systemic inflammation increased the sera antioxidant enzymes paraoxonase-1 and superoxide dismutase-2 and decreased the proinflammatory TNFα and IL-1β levels in the liver and small intestine. No toxicity was induced by PGR either in vitro or in vivo. In conclusion, the phytosome formulation of GINex and ROSAex we developed resulted in stable complexes for oral administration with increased bioavailability, antioxidant and anti-inflammatory potential of their active compounds.

pH-responsive microparticles of rifampicin for augmented intramacrophage uptake and enhanced antitubercular efficacy

In this study we present pH-responsive rifampicin (RIF) microparticles comprising lecithin and a biodegradable hydrophobic polymer, polyethylene sebacate (PES), to achieve high intramacrophage delivery and enhanced antitubercular efficacy. PES and PES-lecithin combination microparticles (PL MPs) prepared by single step precipitation revealed average size of 1.5 to 2.7 µm, entrapment efficiency ∼ 60 %, drug loading 12-15 % and negative zeta potential. Increase in lecithin concentration enhanced hydrophilicity. PES MPs demonstrated faster release in simulated lung fluid pH 7.4, while lecithin MPs facilitated faster and concentration dependent release in acidic artificial lysosomal fluid (ALF) pH 4.5 due to swelling and destabilization confirmed by TEM. PES and PL (1:2) MPs exhibited comparable macrophage uptake which was ∼ 5-fold superior than free RIF, in the RAW 264.7 macrophage cells. Confocal microscopy depicted intensified accumulation of the MPs in the lysosomal compartment, with augmented release of coumarin dye from the PL MPs, confirming pH-triggered increased intracellular release. Although, PES MPs and PL (1:2) MPs displayed comparable and high macrophage uptake, antitubercular efficacy against macrophage internalised M. tuberculosis was significantly higher with PL (1:2) MPs. This suggested great promise of the pH-sensitive PL (1:2) MPs for enhanced antitubercular efficacy.

Inflammation, Mitochondria and Natural Compounds Together in the Circle of Trust

Human diseases are characterized by the perpetuation of an inflammatory condition in which the levels of Reactive Oxygen Species (ROS) are quite high. Excessive ROS production leads to DNA damage, protein carbonylation and lipid peroxidation, conditions that lead to a worsening of inflammatory disorders. In particular, compromised mitochondria sustain a stressful condition in the cell, such that mitochondrial dysfunctions become pathogenic, causing human disorders related to inflammatory reactions. Indeed, the triggered inflammation loses its beneficial properties and turns harmful if dysregulation and dysfunctions are not addressed. Thus, reducing oxidative stress with ROS scavenger compounds has proven to be a successful approach to reducing inflammation. Among these, natural compounds, in particular, polyphenols, alkaloids and coenzyme Q₁₀, thanks to their antioxidant properties, are capable of inhibiting the activation of NF-κB and the expression of target genes, including those involved in inflammation. Even more, clinical trials, and in vivo and in vitro studies have demonstrated the antioxidant and anti-inflammatory effects of phytosomes, which are capable of increasing the bioavailability and effectiveness of natural compounds, and have long been considered an effective non-pharmacological therapy. Therefore, in this review, we wanted to highlight the relationship between inflammation, altered mitochondrial oxidative activity in pathological conditions, and the beneficial effects of phytosomes. To this end, a PubMed literature search was conducted with a focus on various in vitro and in vivo studies and clinical trials from 2014 to 2022.

Development of pH-Sensitive Magnetoliposomes Containing Shape Anisotropic Nanoparticles for Potential Application in Combined Cancer Therapy

Late diagnosis and systemic toxicity associated with conventional treatments make oncological therapy significantly difficult. In this context, nanomedicine emerges as a new approach in the prevention, diagnosis and treatment of cancer. In this work, pH-sensitive solid magnetoliposomes (SMLs) were developed for controlled release of the chemotherapeutic drug doxorubicin (DOX). Shape anisotropic magnetic nanoparticles of magnesium ferrite with partial substitution by calcium (Mg_0.75Ca_0.25Fe₂O₄) were synthesized, with and without calcination, and their structural, morphological and magnetic properties were investigated. Their superparamagnetic properties were evaluated and heating capabilities proven, either by exposure to an alternating magnetic field (AMF) (magnetic hyperthermia) or by irradiation with near-infrared (NIR) light (photothermia). The Mg_0.75Ca_0.25Fe₂O₄ calcined nanoparticles were selected to integrate the SMLs, surrounded by a lipid bilayer of DOPE:Ch:CHEMS (45:45:10). DOX was encapsulated in the nanosystems with an efficiency above 98%. DOX release assays showed a much more efficient release of the drug at pH = 5 compared to the release kinetics at physiological pH. By subjecting tumor cells to DOX-loaded SMLs, cell viability was significantly reduced, confirming that they can release the encapsulated drug. These results point to the development of efficient pH-sensitive nanocarriers, suitable for a synergistic action in cancer therapy with magnetic targeting, stimulus-controlled drug delivery and dual hyperthermia (magnetic and plasmonic) therapy.

Recent Preclinical and Clinical Progress in Liposomal Doxorubicin

Doxorubicin (DOX) is a potent anti-cancer agent that has garnered great interest in research due to its high efficacy despite dose-limiting toxicities. Several strategies have been exploited to enhance the efficacy and safety profile of DOX. Liposomes are the most established approach. Despite the improvement in safety properties of liposomal encapsulated DOX (in Doxil and Myocet), the efficacy is not superior to conventional DOX. Functionalized (targeted) liposomes present a more effective system to deliver DOX to the tumor. Moreover, encapsulation of DOX in pH-sensitive liposomes (PSLs) or thermo-sensitive liposomes (TSLs) combined with local heating has improved DOX accumulation in the tumor. Lyso-thermosensitive liposomal DOX (LTLD), MM-302, and C225-immunoliposomal(IL)-DOX have reached clinical trials. Further functionalized PEGylated liposomal DOX (PLD), TSLs, and PSLs have been developed and evaluated in preclinical models. Most of these formulations improved the anti-tumor activity compared to the currently available liposomal DOX. However, the fast clearance, the optimization of ligand density, stability, and release rate need more investigations. Therefore, we reviewed the latest approaches applied to deliver DOX more efficiently to the tumor, preserving the benefits obtained from FDA-approved liposomes.

DoE development of ionic gradient liposomes: A successful approach to improve encapsulation, prolong anesthesia and decrease the toxicity of etidocaine

Etidocaine (EDC) is a long-acting local anesthetic of the aminoamide family whose use was discontinued in 2008 for alleged toxicity issues. Ionic gradient liposomes (IGL) are nanostructured carriers for which an inner/outer gradient of ions increases drug upload. This work describes IGL_EDC, a formulation optimized by Design of Experiments, composed of hydrogenated soy phosphatidylcholine:cholesterol:EDC, and characterized by DLS, NTA, TEM/Cryo-TEM, DSC and ¹H NMR. The optimized IGL showed significant encapsulation efficiency (41 %), good shelf stability (180 days) and evidence of EDC interaction with the lipid bilayer (as seen by DSC and ¹H NMR results) that confirms its membrane permeation. In vitro (release kinetics and cytotoxicity) tests showed that the encapsulation of EDC into the IGL promoted sustained release for 24 h and decreased by 50 % the intrinsic toxicity of EDC to Schwann cells. In vivo IGL_EDC decreased the toxicity of EDC to Caenorhabditis elegans by 25 % and extended its anesthetic effect by one hour, after infiltrative administration, at clinically used (0.5 %) concentration, in rats. Thus, this novel drug delivery system is a promise for the possible reintroduction of EDC in clinics, aiming at the control of operative and postoperative pain.

Liposomal form of erlotinib for local inhalation administration and efficiency of its transport to the lungs

This contribution is focused on the preparation of a liposomal drug delivery system of erlotinib resisting the nebulization process that could be used for local treatment of non-small-cell lung cancer. Liposomes with different compositions were formulated to reveal their influence on the encapsulation efficiency of erlotinib. An encapsulation efficiency higher than 98 % was achieved for all vesicles containing phosphatidic acid (d ≈ 100 nm, ζ = - 43 mV) even in the presence of polyethylene glycol (d ≈ 150 nm, ζ = - 17 mV) which decreased this value in all other formulas. The three most promising formulations were nebulized by two air-jet and two vibrating mesh nebulizers, and the aerosol deposition in lungs was calculated by tools of computational fluid and particle mechanics. According to the numerical simulations and measurements of liposomal stability, air-jet nebulizers generated larger portion of the aerosol able to penetrate deeper into the lungs, but the delivery is likely to be more efficient when the formulation is administered by Aerogen Solo vibrating mesh nebulizer because of a higher portion of intact vesicles after the nebulization. The leakage of encapsulated drug from liposomes nebulized by this nebulizer was lower than 2 % for all chosen vesicles.

Systematic modulation of the lipid composition enables the tuning of liposome cellular uptake

As liposomes have been widely explored as drug delivery carriers over the past decades, they are one of the most promising platforms due to their biocompatibility and versatility for surface functionalization. However, to improve the specific design of liposomes for future biomedical applications such as nanovaccines, it is necessary to understand how these systems interact with cell membranes, as most of their potential applications require them to be internalized by cells. Even though several investigations on the cellular uptake of liposomes were conducted, the effect of the liposome membrane properties on internalization in different cell lines remains unclear. Here, we demonstrate how the cellular uptake behavior of liposomes can be driven towards preferential interaction with dendritic cells (DC2.4) as compared to macrophages (RAW264.7) by tuning the lipid composition with varied molar ratios of the lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). Cellular internalization efficiency was analyzed by flow cytometry, as well as liposome-cell membrane co-localization by confocal laser scanning microscopy. The corresponding proteomic analysis of the protein corona was performed in order to unravel the possible effect on the internalization. The obtained results of this work reveal that it is possible to modulate the cellular uptake towards enhanced internalization by dendritic cells just by modifying the applied lipids and, thus, mainly the physico-chemical properties of the liposomes. STATEMENT OF SIGNIFICANCE: In the field of nanomedicine, it is of key importance to develop new specific and efficient drug carriers. In this sense, liposomes are one of the most widely known carrier types and used in clinics with good results. However, the exact interaction mechanisms of liposomes with cells remain unclear, which is of great importance for the design of new drug delivery platforms. Therefore, in this work we demonstrate that cellular uptake depends on the lipid composition. We are able to enhance the uptake in a specific cell type just by tuning the content of a lipid in the liposome membrane. This finding could be a step towards the selective design of liposomes to be internalized by specific cells with promising applications in biomedicine.

A review on microfluidic-assisted nanoparticle synthesis, and their applications using multiscale simulation methods

Recent years have witnessed an increased interest in the development of nanoparticles (NPs) owing to their potential use in a wide variety of biomedical applications, including drug delivery, imaging agents, gene therapy, and vaccines, where recently, lipid nanoparticle mRNA-based vaccines were developed to prevent SARS-CoV-2 causing COVID-19. NPs typically fall into two broad categories: organic and inorganic. Organic NPs mainly include lipid-based and polymer-based nanoparticles, such as liposomes, solid lipid nanoparticles, polymersomes, dendrimers, and polymer micelles. Gold and silver NPs, iron oxide NPs, quantum dots, and carbon and silica-based nanomaterials make up the bulk of the inorganic NPs. These NPs are prepared using a variety of top-down and bottom-up approaches. Microfluidics provide an attractive synthesis alternative and is advantageous compared to the conventional bulk methods. The microfluidic mixing-based production methods offer better control in achieving the desired size, morphology, shape, size distribution, and surface properties of the synthesized NPs. The technology also exhibits excellent process repeatability, fast handling, less sample usage, and yields greater encapsulation efficiencies. In this article, we provide a comprehensive review of the microfluidic-based passive and active mixing techniques for NP synthesis, and their latest developments. Additionally, a summary of microfluidic devices used for NP production is presented. Nonetheless, despite significant advancements in the experimental procedures, complete details of a nanoparticle-based system cannot be deduced from the experiments alone, and thus, multiscale computer simulations are utilized to perform systematic investigations. The work also details the most common multiscale simulation methods and their advancements in unveiling critical mechanisms involved in nanoparticle synthesis and the interaction of nanoparticles with other entities, especially in biomedical and therapeutic systems. Finally, an analysis is provided on the challenges in microfluidics related to nanoparticle synthesis and applications, and the future perspectives, such as large-scale NP synthesis, and hybrid formulations and devices.

Nano-formulations for bone-specific delivery of siRNA for CrkII silencing-induced regulation of bone formation and resorption to maximize therapeutic potential for bone-related diseases

CrkII, a member of the adaptor protein family, is known to participate in bone homeostasis via the regulation of osteoclasts and osteoblasts. Therefore, silencing CrkII would beneficially impact the bone microenvironment. In this study, CrkII siRNA encapsulated by a bone-targeting peptide (AspSerSer)₆-liposome was evaluated for its therapeutic applications using a receptor activator of nuclear factor kappa-B ligand (RANKL)-induced bone loss model. (AspSerSer)₆-liposome-siCrkII maintained its gene-silencing ability in both osteoclasts and osteoblasts in vitro and significantly reduced osteoclast formation while increasing osteoblast differentiation in vitro. Fluorescence image analyses showed that the (AspSerSer)₆-liposome-siCrkII was present largely in bone, where it remained present for up to 24 hours and was cleared by 48 hours, even when systemically administrated. Importantly, microcomputed-tomography revealed that bone loss induced by RANKL administration was recovered by systemic administration of (AspSerSer)₆-liposome-siCrkII. Collectively, the findings of this study suggest that (AspSerSer)₆-liposome-siCrkII is a promising therapeutic strategy for the development of treatments for bone diseases, as it overcomes the adverse effects derived from ubiquitous expression via bone-specific delivery of siRNA.

Liposomal Doxorubicin: the Sphingomyelin/Cholesterol System Significantly Enhances the Antitumor Efficacy of Doxorubicin

Doxorubicin (DOX) has a cytotoxic effect on many tumor cells; however, its clinical application is limited owing to its strong side effects. Although Doxil® reduces the cardiotoxicity of free DOX, it has also introduced a new dose-limiting toxicity. In a previous study, a sialic acid-cholesterol conjugate (SA-CH) was synthesized and modified onto the surface of DOX-loaded liposomes to target tumor-associated macrophages (TAMs), further improving the efficacy of DOX-loaded liposomes over that of Doxil®. Meanwhile, the good retention characteristics and promising antitumor ability of sphingomyelin/cholesterol (SM/CH) system for water-soluble drugs have attracted wide attention. Therefore, we aimed to use SA-CH as the target and hydrogenated soybean phosphatidylcholine (HSPC) or egg sphingomyelin (ESM) as the membrane material to develop a more stable DOX-loaded liposome with stronger antitumor activity. The liposomes were evaluated for particle size, polydispersity index, zeta potential, entrapment efficiency, in vitro release, long-term storage, cytotoxicity, cellular uptake, pharmacokinetics, tumor targetability, and in vivo antitumor activity. In the liposomes prepared using HSPC/CH, sialic acid (SA) modification considerably increased the accumulation of DOX-loaded liposomes in the tumor, thus exerting a better antitumor effect. However, SA modification in DOX-ESL (SA-CH-modified DOX-loaded liposomes prepared by ESM/CH) destroyed the strong retention effect of the ESM/CH system on DOX, resulting in a reduced antitumor effect. Notably, DOX-ECL (DOX-loaded liposome prepared by ESM/CH) had the optimal storage stability, lowest toxicity, and optimal antitumor effect due to better drug retention properties. Thus, the ESM/CH liposome of DOX is a potential drug delivery system. Sketch of the effect of two DOX-loaded liposomes with hydrogenated soybean phospholipid (HSPC) and egg sphingomyelin (ESM) as lipid membrane material and surface-modified SA derivative on tumor growth inhibition.

Advanced Phytochemical-Based Nanocarrier Systems for the Treatment of Breast Cancer

As the world's most prevalent cancer, breast cancer imposes a significant societal health burden and is among the leading causes of cancer death in women worldwide. Despite the notable improvements in survival in countries with early detection programs, combined with different modes of treatment to eradicate invasive disease, the current chemotherapy regimen faces significant challenges associated with chemotherapy-induced side effects and the development of drug resistance. Therefore, serious concerns regarding current chemotherapeutics are pressuring researchers to develop alternative therapeutics with better efficacy and safety. Due to their extremely biocompatible nature and efficient destruction of cancer cells via numerous mechanisms, phytochemicals have emerged as one of the attractive alternative therapies for chemotherapeutics to treat breast cancer. Additionally, phytofabricated nanocarriers, whether used alone or in conjunction with other loaded phytotherapeutics or chemotherapeutics, showed promising results in treating breast cancer. In the current review, we emphasize the anticancer activity of phytochemical-instigated nanocarriers and phytochemical-loaded nanocarriers against breast cancer both in vitro and in vivo. Since diverse mechanisms are implicated in the anticancer activity of phytochemicals, a strong emphasis is placed on the anticancer pathways underlying their action. Furthermore, we discuss the selective targeted delivery of phytofabricated nanocarriers to cancer cells and consider research gaps, recent developments, and the druggability of phytoceuticals. Combining phytochemical and chemotherapeutic agents with nanotechnology might have far-reaching impacts in the future.

Advancing Medicine with Lipid-Based Nanosystems-The Successful Case of Liposomes

Nanomedicine, a promising area of medicine, employs nanosized tools for the diagnosis, prevention, and treatment of disease. Particularly, liposomes, lipid-based nanovesicles, are currently one of the most successful nanosystems, with extensive applications in the clinic and an increasing pipeline of products in preclinical and clinical development. These versatile nanotechnological tools are biocompatible and biodegradable, and can load a variety of molecules and, ultimately, improve the therapeutic performance of drugs while minimizing undesired side effects. In this review, we provide a brief description on liposomes' composition and classification and mainly focus on their clinical use in various areas, including disease management (e.g., cancer, fungal and bacterial infections, ocular pathologies), analgesia, vaccination, diagnostics, and immunosuppression in organ transplantation. Herein are described examples of current liposomal products already in the clinic, as well as the most recent clinical trials involving liposomes as effective and safe nanomedicine tools.

Effects of imidacloprid-contaminated feed exposure on spermatogenic cells and Leydig cells in testes of adult male rabbits (Oryctolagus cuniculus)

This research was undertaken to assess the results of repeated exposure to the insecticide; imidacloprid (IMI)-contaminated feed on testicular tissue, spermatogenic cell population, Leydig cell number, and sperm morphology in adult male rabbits (n = 24). The treatment groups received IMI (Bildor® 100 mg/L water spray on green grass)-contaminated green grass without wash (n = 8, not-washed-feed rabbit group) and after wash (n = 8, washed-feed rabbit group) once daily for two weeks on an alternate day basis. The rest of the rabbits, as control, received a normal pesticide-free standard feed. During the exposure time, there was no evident toxic symptom found on regular monitoring of IMI-treated rabbits. Histopathologically, the thickness of tunica albuginea of testes reduced significantly with loosely arranged connective tissues in IMI-treated rabbits. Within the testes, the bizarre-shaped seminiferous tubules were seen with increased lumen diameter in IMI-treated rabbits. The spermatogenic cells were disorganized and detached from the basement membrane in seminiferous tubules of IMI-exposed testes of rabbits. The spermatogenic cell population decreased significantly (P < 0.05) in IMI-treated rabbits compared to control rabbits. Leydig cell number decreased significantly (P < 0.05) in IMI-treated rabbits. A high percentage of morphologically abnormal spermatozoa was seen in IMI-treated rabbits. The degree of the histopathological changes was more prominent in the testes of IMI-exposed not-washed-feed rabbits. The results showed that insecticide-IMI has toxicological effects on testicular tissues, mainly spermatogenic and Leydig cell population of adult rabbits which may cause infertility. A short running title: Effect of imidacloprid on testicular tissue of rabbits.

Interactions between DMPC Model Membranes, the Drug Naproxen, and the Saponin β-Aescin

In this study, the interplay among the phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) as a model membrane, the nonsteroidal anti-inflammatory drug naproxen, and the saponin β-aescin are investigated. The naproxen amount was fixed to 10 mol%, and the saponin amount varies from 0.0 to 1.0 mol%. Both substances are common ingredients in pharmaceutics; therefore, it is important to obtain deeper knowledge of their impact on lipid membranes. The size and properties of the DMPC model membrane upon naproxen and aescin addition were characterized with differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS, WAXS), and photon correlation spectroscopy (PCS) in a temperature-dependent study. The interaction of all substances was dependent on the lipid phase state, which itself depends on the lipid's main phase transition temperature Tm. The incorporation of naproxen and aescin distorted the lipid membrane structure and lowers Tm. Below Tm, the DMPC-naproxen-aescin mixtures showed a vesicle structure, and the insertion of naproxen and aescin influenced neither the lipid chain-chain correlation distance nor the membrane thickness. Above Tm, the insertion of both molecules instead induced the formation of correlated bilayers and a decrease in the chain-chain correlation distance. The presented data clearly confirm the interaction of naproxen and aescin with DMPC model membranes. Moreover, the incorporation of both additives into the model membranes is evidenced.

Liposomes or Extracellular Vesicles: A Comprehensive Comparison of Both Lipid Bilayer Vesicles for Pulmonary Drug Delivery

The rapid and non-invasive pulmonary drug delivery (PDD) has attracted great attention compared to the other routes. However, nanoparticle platforms, like liposomes (LPs) and extracellular vesicles (EVs), require extensive reformulation to suit the requirements of PDD. LPs are artificial vesicles composed of lipid bilayers capable of encapsulating hydrophilic and hydrophobic substances, whereas EVs are natural vesicles secreted by cells. Additionally, novel LPs-EVs hybrid vesicles may confer the best of both. The preparation methods of EVs are distinguished from LPs since they rely mainly on extraction and purification, whereas the LPs are synthesized from their basic ingredients. Similarly, drug loading methods into/onto EVs are distinguished whereby they are cell- or non-cell-based, whereas LPs are loaded via passive or active approaches. This review discusses the progress in LPs and EVs as well as hybrid vesicles with a special focus on PDD. It also provides a perspective comparison between LPs and EVs from various aspects (composition, preparation/extraction, drug loading, and large-scale manufacturing) as well as the future prospects for inhaled therapeutics. In addition, it discusses the challenges that may be encountered in scaling up the production and presents our view regarding the clinical translation of the laboratory findings into commercial products.

Perspectives on lecithin from egg yolk: Extraction, physicochemical properties, modification, and applications

Egg yolk lecithin has physiological activities as an antioxidant, antibacterial, anti-inflammatory, and neurologic, cardiovascular, and cerebrovascular protectant. There are several methods for extracting egg yolk lecithin, including solvent extraction and supercritical extraction. However, changes in extraction methods and functional activity of egg yolk lecithin are a matter of debate. In this review we summarized the molecular structure, extraction method, and functional activity of egg yolk lecithin to provide a good reference for the development of egg yolk lecithin products in the future.

Current advancements related to phytobioactive compounds based liposomal delivery for neurodegenerative diseases

Neurodegenerative diseases are the most widely affected disease condition in an aging population. The treatment available reduces the elevated manifestations but is ineffective due to the drug's poor bioavailability, plasma stability, and permeability across the blood-brain barrier (BBB). Until now, no therapeutic compound has been able to stop the progression of neurodegenerative disease. Even the available therapeutic moiety manages it with possible adverse effects up to the later stage. Hence, phytobioactive compounds of plant origin offer effective treatment strategies against neurodegenerative diseases. The only difficulty of these phytobioactive compounds is permeability across the BBB. Engineered nanocarriers such as liposomes provide high lipid permeability across BBB. Liposomes have unique physicochemical properties that are widely investigated for their application in diagnosing and treating neurodegenerative diseases. The surface modification on liposomes by peptides, antibodies, and RNA aptamers offers receptor targeting. These brain-targeted approaches by liposomes improve the efficacy of phytoconstituents. Additional surface modification methods are utilized on liposomes, which increases the brain-targeted delivery of phytobioactive compounds. The marketing strategy of the liposomal delivery system is in its peak mode, where it has the potential to modify the existing therapy. This review will summarize the brain target liposomal delivery of phytobioactive compounds as a novel disease-modifying agent for treating neurodegenerative diseases.

Doxorubicin-loaded liposomes surface engineered with the matrix metalloproteinase-2 cleavable polyethylene glycol conjugate for cancer therapy

Background

Colorectal cancer is one of the prominent leading causes of fatality worldwide. Despite recent advancements within the field of cancer therapy, the cure rates and long-term survivals of patients suffering from colorectal cancer have changed little. The application of conventional chemotherapeutic agents like doxorubicin is limited by some drawbacks such as cardiotoxicity and hematotoxicity. Therefore, nanotechnology has been exploited as a promising solution to address these problems. In this study, we synthesized and compared the anticancer efficacy of doxorubicin-loaded liposomes that were surface engineered with the 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-matrix metalloproteinase-2 (MMP-2) cleavable peptide-polyethylene glycol (PEG) conjugate. The peptide linker was used to cleave in response to the upregulated MMP-2 in the tumor microenvironment, thus exposing a positive charge via PEG-deshielding and enhancing liposomal uptake by tumor cells/vasculature. Liposomal formulations were characterized in terms of size, surface charge and morphology, drug loading, release properties, cell binding and uptake, and cytotoxicity.

Results

The formulations had particle sizes of ~ 100-170 nm, narrow distribution (PDI ˂ 0.2), and various surface charges (- 10.2 mV to + 17.6 mV). MMP-2 overexpression was shown in several cancer cell lines (C26, 4T1, and B16F10) as compared to the normal NIH-3T3 fibroblast cells by gelatin zymography and qRT-PCR. In vitro results demonstrated enhanced antitumor efficacy of the PEG-cleavable cationic liposomes (CLs) as compared to the commercial Caelyx^® (up to fivefold) and the chick chorioallantoic membrane assay showed their great antiangiogenesis potential to target and suppress tumor neovascularization. The pharmacokinetics and efficacy studies also indicated higher tumor accumulation and extended survival rates in C26 tumor-bearing mice treated with the MMP-2 cleavable CLs as compared to the non-cleavable CLs with no remarkable sign of toxicity in healthy tissues.

Conclusion

Altogether, the MMP-2-cleavable CLs have great potency to improve tumor-targeted drug delivery and cellular/tumor-vasculature uptake which merits further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12645-023-00169-8.

Pluronic® triblock copolymer-based nanoformulations for cancer therapy: A 10-year overview

This paper provides a review of the literature on the use of Pluronic® triblock copolymers for drug encapsulation over the last 10 years. A special focus is given to the progress of drug delivery systems (e.g., micelles, liposomes, micro/nanoemulsions, hydrogels and nanogels, and polymersomes and niosomes); the beneficial aspects of Pluronic® triblock copolymers as biological response modifiers and as pharmaceutical additives, adjuvants, and stabilizers, are also discussed. The advantages and limitations encountered in developing site-specific targeting approaches based on Pluronic-based nanostructures in cancer treatment are highlighted, in addition to innovative examples for improving tumor cytotoxicity while reducing side effects.

Interaction of GC376, a SARS-COV-2 MPRO inhibitor, with model lipid membranes

Partitioning and effect of antiviral GC376, a potential SARS-CoV-2 inhibitor, on model lipid membranes was studied using dynamic light scattering (DLS), UV–VIS spectrometry, Excimer fluorescence, Differential scanning calorimetry (DSC) and Small- and Wide-angle X-ray scattering (SAXS/WAXS). Partition coefficient of GC376 between lipid and water phase was found to be low, reaching K_P = 46.8 ± 18.2. Results suggest that GC376 partitions into lipid bilayers at the level of lipid head-groups, close to the polar/hydrophobic interface. Changes in structural and thermodynamic properties strongly depend on the GC376/lipid mole ratio. Already at lowest mole ratios GC376 induces increase of lateral pressures, mainly in the interfacial region of the bilayer. Hereby, the pre- and main-transition temperature of the lipid system increases, what is attributed to tighter packing of acyl chains induced by GC376. At GC376/DPPC ≥ 0.03 mol/mol we detected formation of domains with different GC376 content resulting in the lateral phase separation and changes in both, main transition temperature and enthalpy. The observed changes are attributed to the response of the system on the increased lateral stresses induced by partitioning of GC376. Obtained results are discussed in context of liposome-based drug delivery systems for GC376 and in context of indirect mechanism of virus replication inhibition.

Wound Healing Efficacy of Rosuvastatin Transethosomal Gel, I Optimal Optimization, Histological and In Vivo Evaluation

This study aimed to make a formulation and statistical optimization of transethosomal formulations of rosuvastatin (ROS) to enhance its topical wound healing efficiency. Design-Expert^® software was used to employ I optimal design. The formulation variables in the study were surfactant concentration (%w/v), ethanol concentration (%w/v) and surfactant type (span 60 or tween 80), while the dependent responses were entrapment efficiency percent (EE%), vesicle size (VS) and zeta potential (ZP). The numerical optimization process employed by the design expert software resulted in an optimum formula composed of 0.819439 (%w/v) span 60, 40 (%w/v) ethanol and 100 mg lecithin with a desirability of 0.745. It showed a predicted EE% value of 66.5517 vs. 277.703 nm and a ZP of -33. When it was prepared and validated, it showed less than a 5% deviation from the predicted values. The optimum formula was subjected to further characterizations, such as DSC, XRD, TEM, in vitro release, the effect of aging and wound healing efficiency. The DSC thermogram made a confirmation of the compatibility of ROS with the ingredients used in the formulation. XRD showed the encapsulation of ROS in the transethosomal vesicles. The TEM image pointed out the spherical nature of the nanovesicles with the absence of aggregation. Additionally, the optimum formula revealed an enhancement of drug release in comparison with the drug suspension. It also showed good stability for one month. Furthermore, it revealed good wound healing efficiency when compared with the standard silver sulphadiazine (1% w/w) ointment or the drug-loaded gel, which could be related to the enhanced penetration of the nanosized vesicles of TESMs into the skin, which enhances the wound healing process. So, it could be regarded as a promising carrier of ROS for the treatment of chronic wounds.

Single-Molecule Trapping and Measurement in a Nanostructured Lipid Bilayer System

The repulsive electrostatic force between a biomolecule and a like-charged surface can be geometrically tailored to create spatial traps for charged molecules in solution. Using a parallel-plate system composed of silicon dioxide surfaces, we recently demonstrated single-molecule trapping and high precision molecular charge measurements in a nanostructured free energy landscape. Here we show that surfaces coated with charged lipid bilayers provide a system with tunable surface properties for molecular electrometry experiments. Working with molecular species whose effective charge and geometry are well-defined, we demonstrate the ability to quantitatively probe the electrical charge density of a supported lipid bilayer. Our findings indicate that the fraction of charged lipids in nanoslit lipid bilayers can be significantly different from that in the precursor lipid mixtures used to generate them. We also explore the temporal stability of bilayer properties in nanofluidic systems. Beyond their relevance in molecular measurement, such experimental systems offer the opportunity to examine lipid bilayer formation and wetting dynamics on nanostructured surfaces.

Temperature and oxidation-sensitive dioleoylphophatidylethanolamine liposome stabilized with poly(ethyleneimine)/(phenylthio)acetic acid ion pair

Temperature and oxidation-sensitive liposomes were prepared by stabilizing dioleoylphosphatidylethanolamine (DOPE) bilayers with the ion pair of poly(ethyleneimine)/(phenylthio)acetic acid (PEI/PTA). An upper critical solution temperature (UCST) behavior was observed when PEI/PTA ion pair was suspended in an aqueous solution. It was observed that the UCST increased with increasing PTA content. The ion pair was self-assembled into nanospheres owing to its amphiphilic property which was confirmed by transmission electron microscopy. The FT-IR spectroscopic spectrum showed that the ion pair formed a salt bridge between the amino group and the carboxyl group and the PTA content in the ion pair was readily oxidized by H₂O₂. Further, DOPE liposomal membranes could be stabilized with PEI/PTA ion pair. Due to the amphiphilic property, the ion pair played a role as a stabilizer for the formation of DOPE liposomes. The liposome released its payload in a temperature-responsive manner, possibly because when the temperature is raised, the ion pair loses its amphiphilic property and can be detached from the liposomal membrane. The liposome was also oxidation-responsive in terms of release, possibly because the amphiphilic property of the ion pair disappears when the PTA is oxidized.

Antioxidant Effect of Octopus Byproducts in Canned Horse Mackerel (Trachurus trachurus) Previously Subjected to Different Frozen Storage Times

The effects on lipid damage in canned horse mackerel (Trachurus trachurus) of a prior frozen storage (−18 °C) period and the presence of an octopus (Octopus vulgaris) cooking juice (OCJ) in the packing medium were investigated. An increase of the frozen storage time favoured an increase (p < 0.05) of free fatty acid (FFA), peroxide, and thiobarbituric acid reactive substance contents and a decrease (p < 0.05) of the phospholipid (PL) value and polyene index. Furthermore, an increased presence of OCJ in the packing medium led to an inhibitory effect (p < 0.05) on fluorescent compound formation as well as to a retention (p < 0.05) of the PL and FFA compounds. Colour determination showed a substantial increase (p < 0.05) of L* and b* values in canned fish with previous frozen storage time. Nevertheless, this increase was partly reduced (p < 0.05) by the OCJ presence in the packing medium. It is concluded that previous holding time has led to an increased lipid oxidation development and loss of beneficial lipid constituents (i.e., PLs and polyunsaturated fatty acids). Remarkably, the presence in the packing medium of preservative compounds (i.e., antioxidants) included in waste juice obtained from octopus processing provided an effective tool for lipid preservation and quality enhancement in canned fish.