Solid lipid nanoparticles for the controlled delivery of poorly water soluble non-steroidal anti-inflammatory drugs

Lipid nanoparticle encapsulated oleic acid induced lipotoxicity to hepatocytes via ROS overload and the DDIT3/BCL2/BAX/Caspases signaling in vitro and in vivo

BACKGROUND

To date, Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disease associated with clinical complications. Dietary fatty acids have been suggested to be involved in preventing or reversing the accumulation of hepatic fat. However, contradicting roles of monounsaturated fatty acids to the liver have been implicated in various human and murine models, mainly due to the insolubility nature of fatty acids.

METHODS

High pressure homogenization methods were used to fabricate oleic acid embedded lipid nanoparticles (OALNs). The in vitro and in vivo models were used to validate the physiological effect of this OALNs via various cellular and molecular approaches including cell viability essay, fluorescent staining, electron microscope, RNAseq, qPCR, Western blots, and IHC staining.

RESULTS

We successfully fabricated OALNs with enhanced stability and solubility. More importantly, lipid accumulation was successfully induced in hepatocytes via the application of OALNs in a dose-dependent manner. Overload of OALNs resulted in ROS accumulation and apoptosis of hepatocytes dose-dependently. With the help of transcriptome sequencing and traditional experimental approaches, we demonstrated that the lipotoxic effect induced by OALNs was exerted via the DDIT3/BCL2/BAX/Caspases signaling. Moreover, we also verified that OALNs induced steatosis and subsequent apoptosis in the liver of mice via the activation of DDIT3 in vivo.

CONCLUSIONS

In all, our results established a potential pathogenic model of NAFLD for further studies and indicated the possible involvement of DDIT3 signaling in abnormal steatosis process of the liver.

Liposomes to Cubosomes: The Evolution of Lipidic Nanocarriers and Their Cutting-Edge Biomedical Applications

Lipidic nanoparticles have undergone extensive research toward the exploration of their diverse therapeutic applications. Although several liposomal formulations are in the clinic (e.g., DOXIL) for cancer therapy, there are many challenges associated with traditional liposomes. To address these issues, modifications in liposomal structure and further functionalization are desirable, leading to the emergence of solid lipid nanoparticles and the more recent liquid lipid nanoparticles. In this context, "cubosomes", third-generation lipidic nanocarriers, have attracted significant attention due to their numerous advantages, including their porous structure, structural adaptability, high encapsulation efficiency resulting from their extensive internal surface area, enhanced stability, and biocompatibility. Cubosomes offer the potential for both enhanced cellular uptake and controlled release of encapsulated payloads. Beyond cancer therapy, cubosomes have demonstrated effectiveness in wound healing, antibacterial treatments, and various dermatological applications. In this review, the authors provide an overview of the evolution of lipidic nanocarriers, spanning from conventional liposomes to solid lipid nanoparticles, with a special emphasis on the development and application of cubosomes. Additionally, it delves into recent applications and preclinical trials associated with cubosome formulations, which could be of significant interest to readers from backgrounds in nanomedicine and clinicians.

Green synthesis of carbon quantum dots from teak leaves biomass for in situ precipitation and regenerative-removal of methylene blue-dye

The objective of this study was to completely eliminate environmentally harmful cationic organic dye from aqueous solutions using the one-step ultrasonication method, renowned for its energy efficiency, user-friendliness, and minimal requirement for chemical resources, making it particularly suitable for large-scale applications. To achieve effective environmental remediation, we employed carbon dots derived from teak leaf biomass (TBCDs) layered with graphene oxide. We conducted a thorough characterization of the TBCDs using UV-vis spectroscopy (with absorption peaks at λmax = 208 and 276 nm), FTIR spectroscopy (confirming the presence of various functional groups including -OH, -CH, C = O, COO-, C-O-C, and = C-H), Raman spectroscopy (with bands at 1369 cm-1 (D-Band) and 1550 cm-1 (G-Band), and an intensity ratio (ID/IG) = 0.88, indicating structural defects correlated with the sp3 hybridization sites on the TBCDs), XRD analysis (indicating an amorphous nature of particles), HRTEM imaging (showing homogeneous dispersal of TBCDs with typical sizes ranging from 2 to 10 nm), FESEM analysis (showing a flat surface and minuscule particles), and Zeta potential analysis (revealing a surface charge peak at -51.0 mV). Our adsorption experiments yielded significant results, with a substantial 50.1 % removal rate and an impressive adsorption capacity of 735.2 mg g-1. Theoretical adsorption parameters were rigorously analyzed to understand the adsorption behavior, surface interactions, and mechanisms. Among these models, the Langmuir isotherm in conjunction with pseudo-second-order kinetics provided an exceptional fit (with R2 values closer to 1) for our system. The Gibbs free energy (ΔG) was found to be negative at all temperatures, indicating the spontaneity of the reaction. Regarding mechanism, electrostatic attraction ((+ve) MB dye + (- ve) TBCDs), π-π stacking adsorption facilitated by the graphitic structure, formation of multiple hydrogen bonds due to polar functional groups, and a pore-filling mechanism wherein the cationic MB dye fills the pores of TBCDs with graphene oxide layers, forming an adduct were identified. Furthermore, we demonstrated the regenerative capacity of our system by effectively extracting and recovering the MB dye (with a regeneration rate of 77.1%), utilizing ethyl alcohol as the solvent. These findings not only provide valuable insights into the adsorption capabilities of TBCDs but also highlight the potential of our approach in the recovery of expensive cationic organic dye compounds from polluted environments.

Mucoadhesive Carrier-Mediated Oral Co-delivery of Bcl2 Inhibitors Improves Gastric Cancer Treatment

Gastric cancer treatment is challenging due to the lack of early-stage diagnostic technology and targeted delivery systems. Currently, the available treatments for gastric cancer are surgery, chemotherapy, immunotherapy, and radiation. These strategies are either invasive or require systemic delivery, exerting toxicities within healthy tissues. By creation of a targeted delivery system to the stomach, gastric cancer can be treated in the early stages. Such an approach reduces the negative effects on the rest of the body by minimizing systemic absorbance and random localization. With this in mind, we developed a mucoadhesive vehicle composed of β-Glucan And Docosahexaenoic Acid (GADA) for controlled drug/gene delivery. In the current study, we investigated the therapeutic effect of codelivery Bcl2 inhibitors navitoclax (NAVI) and siRNA (Bcl2) via oral using GADA. The therapeutic efficacy of the GADA-mediated oral NAVI/siRNA was investigated in a gastric cancer mouse model. Higher Bcl2 inhibition efficacy was observed in Western blotting and TUNEL assay in mice treated with GADA/NAVI/siRNA compared to free NAVI, siRNA, and NAVI/siRNA. Histology (H&E) and immunohistochemistry (Ki67, TUNEL, and BCl2) analyses confirmed a significant reduction of the tumor region. Interaction between GADA and mucus resulted in retention for over 6 h and thereby sustained local payload release. The developed oral carrier GADA is an emerging vehicle that has promising potential in oral delivery of both small and large molecules, and their mucoadhesive property results in improved therapeutic efficacy with minimal side effects compared to conventional treatment. This study opens a new window for the effective delivery of oral medicine for the treatment of gastric cancer and other gastrointestinal diseases.

Nanoemulsion: An Emerging Novel Technology for Improving the Bioavailability of Drugs

The pharmaceutical sector has made considerable strides recently, emphasizing improving drug delivery methods to increase the bioavailability of various drugs. When used as a medication delivery method, nanoemulsions have multiple benefits. Their small droplet size, which is generally between 20 and 200 nanometers, creates a significant interfacial area for drug dissolution, improving the solubility and bioavailability of drugs that are weakly water-soluble. Additionally, nanoemulsions are a flexible platform for drug administration across various therapeutic areas since they can encapsulate hydrophilic and hydrophobic medicines. Nanoemulsion can be formulated in multiple dosage forms, for example, gels, creams, foams, aerosols, and sprays by using low-cost standard operative processes and also be taken orally, topically, topically, intravenously, intrapulmonary, intranasally, and intraocularly. The article explores nanoemulsion formulation and production methods, emphasizing the role of surfactants and cosurfactants in creating stable formulations. In order to customize nanoemulsions to particular medication delivery requirements, the choice of components and production techniques is crucial in assuring the stability and efficacy of the finished product. Nanoemulsions are a cutting-edge technology with a lot of potential for improving medication bioavailability in a variety of therapeutic contexts. They are a useful tool in the creation of innovative pharmaceutical formulations due to their capacity to enhance drug solubility, stability, and delivery. Nanoemulsions are positioned to play a crucial role in boosting medication delivery and enhancing patient outcomes as this field of study continues to advance.

Design and development of molten metal nanomaterials using sonochemistry for multiple applications

Molten metals have prospective applications as soft fluids with unique physical and chemical properties, yet materials based on them are still in their infancy and have great potential. Ultrasonic irradiation of molten metals in liquid media induces acoustic cavitation and dispersion of the liquid metal into micrometric and nanometric spheres. This review focuses on the synthesis of mmetallic materials via sonochemistry from molten metals with low melting point (< 420 ᴼC): Ga, Hg, In, Sn, Bi, Pb, and Zn, which can be melted in organic or inorganic media or water and of aqueous solutions of metallic ions to form two immiscible liquid phases. Organic molecule entrapment, polymer solubilization, chiral imprinting, and catalyst incorporation within metals or metallic particles were recently developed to provide novel hybrid nanomaterials for several applications including catalysis, fuel cells, and biomass-to-biofuel conversion. In all cases where molten metal was sonicated in an organic solvent, in addition to a solid precipitant, an interesting supernatant was obtained that contained metal-doped carbon dots (M@C-dots). Some of these M@C-dots were found to exhibit highly effective antimicrobial activity, promote neuronal tissue growth, or have utility in lithium-ion rechargeable batteries. The economic feasibility and commercial scalability of molten metal sonochemistry attract fundamental interest in the reaction mechanisms, as the versatility and controllability of the structure and material properties invite exploration of various applications.

Design and Optimization of Solid Lipid Nanoparticles Loaded with Triamcinolone Acetonide

Principles of quality by design and design of experiments are acquiring more importance in the discovery and application of new drug carriers, such as solid lipid nanoparticles. In this work, an optimized synthesis of solid lipid nanoparticles loaded with Triamcinolone Acetonide is presented using an approach that involves Stearic Acid as a lipid, soy PC as an ionic surfactant, and Tween 80 as a nonionic surfactant. The constructed circumscribed Central Composite Design considers the lipid and nonionic surfactant quantities and the sonication amplitude in order to optimize particle size and Zeta potential, both measured by means of Dynamic Light Scattering, while the separation of unentrapped drug from the optimized Triamcinolone Acetonide-loaded solid lipid nanoparticles formulation is performed by Size Exclusion Chromatography and, subsequently, the encapsulation efficiency is determined by HPLC-DAD. The proposed optimized formulation-with the goal of maximizing Zeta potential and minimizing particle size-has shown good accordance with predicted values of Zeta potential and dimensions, as well as a high value of encapsulated Triamcinolone Acetonide. Experimental values obtained from the optimized synthesis reports a dimension of 683 ± 5 nm, which differs by 3% from the predicted value, and a Zeta potential of -38.0 ± 7.6 mV (12% difference from the predicted value).

An Overview of Nanoemulgels for Bioavailability Enhancement in Inflammatory Conditions via Topical Delivery

The anti-inflammatory drugs that are generally available possess the disadvantage of hydrophobicity, which leads to poor permeability and erratic bioavailability. Nanoemulgels (NEGs) are novel drug delivery systems that aim to improve the solubility and permeability of drugs across the biological membrane. The nano-sized droplets in the nanoemulsion enhance the permeation of the formulation, along with surfactants and co-surfactants that act as permeation enhancers and can further improve permeability. The hydrogel component of NEG helps to increase the viscosity and spreadability of the formulation, making it ideal for topical application. Moreover, oils that have anti-inflammatory properties, such as eucalyptus oil, emu oil and clove oil, are used as oil phases in the preparation of the nanoemulsion, which shows a synergistic effect with active moiety and enhances its overall therapeutic profile. This leads to the creation of hydrophobic drugs that possess enhanced pharmacokinetic and pharmacodynamic properties, and simultaneously avoid systemic side effects in individuals with external inflammatory disorders. The nanoemulsion's effective spreadability, ease of application, non-invasive administration, and subsequent ability to achieve patient compliance make it more suitable for topical application in the combat of many inflammatory disorders, such as dermatitis, psoriasis, rheumatoid arthritis, osteoarthritis and so on. Although the large-scale practical application of NEG is limited due to problems regarding its scalability and thermodynamic instability, which arise from the use of high-energy approaches during the production of the nanoemulsion, these can be resolved by the advancement of an alternative nanoemulsification technique. Considering the potential advantages and long-term benefits of NEGs, the authors of this paper have compiled a review that elaborates the potential significance of utilizing nanoemulgels in a topical delivery system for anti-inflammatory drugs.

Microparticles in the Development and Improvement of Pharmaceutical Formulations: An Analysis of In Vitro and In Vivo Studies

Microparticulate systems such as microparticles, microspheres, microcapsules or any particle in a micrometer scale (usually of 1–1000 µm) are widely used as drug delivery systems, because they offer higher therapeutic and diagnostic performance compared to conventional drug delivery forms. These systems can be manufactured with many raw materials, especially polymers, most of which have been effective in improving the physicochemical properties and biological activities of active compounds. This review will focus on the in vivo and in vitro application in the last decade (2012 to 2022) of different active pharmaceutical ingredients microencapsulated in polymeric or lipid matrices, the main formulation factors (excipients and techniques) and mostly their biological activities, with the aim of introducing and discussing the potential applicability of microparticulate systems in the pharmaceutical field.

Nanotechnology as a tool to overcome macromolecules delivery issues

Nanocarriers can deliver drugs to specific organs or cells, potentially bridging the gap between a drug's function and its interaction with biological systems such as human physiology. The untapped potential of nanotechnology stems from its ability to manipulate materials, allowing control over physical and chemical properties and overcoming drug-related problems, e.g., poor solubility or poor bioavailability. For example, most protein drugs are administered parenterally, each with challenges and peculiarities. Some problems faced by bioengineered macromolecule drugs leading to poor bioavailability are short biological half-life, large size and high molecular weight, low permeability through biological membranes, and structural instability. Nanotechnology emerges as a promising strategy to overcome these problems. Nevertheless, the delivery system should be carefully chosen considering loading efficiency, physicochemical properties, production conditions, toxicity, and regulations. Moving from the bench to the bedside is still one of the major bottlenecks in nanomedicine, and toxicological issues are the greatest challenges to overcome. This review provides an overview of biotech drug delivery approaches, associated nanotechnology novelty, toxicological issues, and regulations.

A Full Factorial Design to Optimize Aminexil Nano Lipid Formulation to Improve Skin Permeation and Efficacy Against Alopecia

Aminexil (AMX) is considered to be one of the most widely used hair growth promoters. Nanostructured lipid carriers (NLC) are employed to increase the permeation of both lipophilic and hydrophilic drugs. Aminexil nanostructured lipid carrier (NLC) designed by pre-emulsion/ultrasonication method was utilized for alopecia treatment. For selecting optimum excipients, a solubility study was executed in liquid lipids, solid lipids, surfactants, and co-surfactants. A 2³ full factorial design was utilized for NLC optimization. Characterization of the developed formulas was performed. The penetration of the optimized formula across cuticle tissues was studied using confocal laser scanning microscopy (CLSM). AMX showed high solubility in glyceryl monostearate (GMS) and stearic acid, 28.87 ± 2.17 and 58.06 ± 2.227 mg/g, respectively. The results of physicochemical characterization showed that formula A7 was the optimized one. It is composed of GMS (solid lipid), oleic acid:garlic oil (1:1 v/v) (liquid lipid), and a surfactant/co-surfactant mixture (Cremophor EL/Transcutol HP). The particle size (PS) was 238.0 ± 2.13 nm, entrapment efficiency (EE) 100.535 ± 6.73%, and zeta potential (ZP) - 29.3 ± 0.93 mv. Ex vivo permeation study demonstrates the potential of AMX-NLC (formula A7) as a delivery system for AMX. The CLSM highly proved AMX-loaded NLC penetration through the skin. The histological study clearly demonstrated that AMX-loaded NLC promoted hair growth more effectively than the market product in chemotherapy-induced alopecia rats. The acquired findings revealed that targeting of AMX-loaded NLC into hair follicles was improved.

Spray-dried Solid Lipid Nanoparticles for Enhancing Berberine Bioavailability via Oral Administration

BACKGROUND

Berberine (BBR), an Eastern traditional medicine, has expressed novel therapeutic activities, especially for chronic diseases like diabetes, hyperlipemia, hypertension, and Alzheimer's disease. However, the low oral bioavailability of BBR has limited the applications of these treatments. Hence, BBRloaded solid lipid nanoparticles (BBR-SLNs) were prepared to improve BBR absorption into systemic circulations via this route.

METHODS

BBR-loaded solid lipid nanoparticles (BBR-SLNs) were prepared by ultrasonication and then transformed into solid form via spray drying technique. The size morphology of BBR-SLNs was evaluated by dynamic light scattering (DLS) and scanning electron microscope (SEM). Crystallinity of BBR and interaction of BBR with other excipients were checked by spectroscopic methods. Entrapment efficiency of BBR-SLNs as well as BBR release in gastrointestinal conditions were also taken into account. Lastly, SLN's cytotoxicity for loading BBR was determined with human embryonic kidney cells (HEK293).

RESULTS

Stearic acid (SA), glyceryl monostearate (GMS), and poloxamer 407 (P407) were selected for BBRSLNs fabrication. BBR-SLNs had homogenous particle sizes of less than 200 nm, high encapsulation efficiency of nearly 90% and loading capacity of above 12%. BBR-SLN powder could be redispersed without significant changes in physicochemical properties and was stable for 30 days. Spray-dried BBR-SLNs showed a better sustained in vitro release profile than BBR-SLNs suspension and BBR during the initial period, followed by complete dissolution of BBR over 24 hours. Notably, cell viability on HEK293 even increased up to 150% compared to the control sample at 100 μg/mL BBR-unloaded SLNs.

CONCLUSION

Hence, SLNs may reveal a promising drug delivery system to broaden BBR treatment for oral administration.

Single pot organic solvent-free thermocycling technology for siRNA-ionizable LNPs: a proof-of-concept approach for alternative to microfluidics

Ionizable LNPs are the latest trend in nucleic acid delivery. Microfluidics technology has recently gained interest owing to its rapid mixing, production of nucleic acid-ionizable LNPs, and stability of nucleic acid inside the body. Industrial scale-up, nucleic acid-lipid long-term storage instability, and high production costs prompted scientists to seek alternate solutions to replace microfluidic technology. We proposed a single-pot, organic solvent-free thermocycling technology to efficiently and economically overcome most of the limitations of microfluidic technology. New thermocycling technology needs optimization of process parameters such as sonication duration, cooling–heating cycle, number of thermal cycles, and lipid:aqueous phase ratio to formulate precisely sized particles, effective nucleic acid encapsulation, and better shelf-life stability. Our research led to the formulation of siRNA-ionizable LNPs with particle sizes of 104.2 ± 34.7 nm and PDI 0.111 ± 0.109, with 83.3 ± 4.1% siRNA encapsulation. Thermocycling siRNA-ionizable LNPs had comparable morphological structures with commercialized microfluidics ionizable LNPs imaged by TEM and cryo-TEM. When compared to microfluidics ionizable LNPs, thermocycling siRNA-ionizable LNPs had a longer shelf life at 4°C. Our thermocycling technology showed an effective alternative to microfluidics technology in the production of nucleic acid–ionizable LNPs to meet global demand.

Thermocycling technology is a low-energy, low-temperature, self-assembling cooling–heating process in which lipid droplets spontaneously break apart into much smaller droplets to form siRNA-ionizable LNPs.

The new technology is an alternative to multistep, costly, and complex microfluidics technology for the formulation and bulk up of siRNA-ionizable LNPs economically.

Thermocycling siRNA-ionizable LNPs formulation focused on optimizing process parameters such as thermal cycle rate, number of thermal cycles, and lipid:aqueous phase ratio.

The thermocycling technology is able to overcome the limitations of the storage stability limitations of commercialized ionizable LNPs.

Optimization of Lipid Nanoparticles by Response Surface Methodology to Improve the Ocular Delivery of Diosmin: Characterization and In-Vitro Anti-Inflammatory Assessment

Diosmin is a flavonoid with a great variety of biological activities including antioxidant and anti-inflammatory ones. Its cytoprotective effect in retinal pigment epithelium cells under high glucose conditions makes it a potential support in the treatment of diabetic retinopathy. Despite its benefits, poor solubility in water reduces its potential for therapeutic use, making it the biggest biopharmaceutical challenge. The design of diosmin-loaded nanocarriers for topical ophthalmic application represents a novelty that has not been yet explored. For this purpose, the response surface methodology (RSM) was used to optimize nanostructured lipid carriers (NLCs), compatible for ocular administration, to encapsulate diosmin and improve its physicochemical issues. NLCs were prepared by a simple and scalable technique: a melt emulsification method followed by ultrasonication. The experimental design was composed of four independent variables (solid lipid concentration, liquid lipid concentration, surfactant concentration and type of solid lipid). The effect of the factors was assessed on NLC size and PDI (responses) by analysis of variance (ANOVA). The optimized formulation was selected according to the desirability function (0.993). Diosmin at two different concentrations (80 and 160 µM) was encapsulated into NLCs. Drug-loaded nanocarriers (D-NLCs) were subjected to a physicochemical and technological investigation revealing a mean particle size of 83.58 ± 0.77 nm and 82.21 ± 1.12 nm, respectively for the D-NLC formulation prepared with diosmin at the concentration of 80 µM or 160 µM, and a net negative surface charge (−18.5 ± 0.60 and −18.0 ± 1.18, respectively for the two batches). The formulations were analyzed in terms of pH (6.5), viscosity, and adjusted for osmolarity, making them more compatible with the ocular environment. Subsequently, stability studies were carried out to assess D-NLC behavior under different storage conditions up to 60 days, indicating a good stability of NLC samples at room temperature. In-vitro studies on ARPE-19 cells confirmed the cytocompatibility of NLCs with retinal epithelium. The effect of D-NLCs was also evaluated in-vitro on a model of retinal inflammation, demonstrating the cytoprotective effect of D-NLCs at various concentrations. RSM was found to be a reliable model to optimize NLCs for diosmin encapsulation.

Nanotechnology-Assisted Metered-Dose Inhalers (MDIs) for High-Performance Pulmonary Drug Delivery Applications

PURPOSE

Respiratory disorders pose a major threat to the morbidity and mortality to public health. Here we reviewed the nanotechnology based pulmonary drug delivery using metered dose inhalers.

METHODS

Major respiratory diseases such as chronic obstructive pulmonary diseases (COPD), asthma, acute lower respiratory tract infections, tuberculosis (TB) and lung cancer. At present, common treatments for respiratory disorders include surgery, radiation, immunotherapy, and chemotherapy or a combination. The major challenge is development of systemic delivery of the chemotherapeutic agents to the respiratory system. Conventional delivery of chemotherapy has various limitation and adverse side effected. Hence, targeted, and systemic delivery need to be developed. Towards this direction nanotechnology, based controlled, targeted, and systemic drug delivery systems are potential candidate to enhance therapeutic efficacy with minimum side effect. Among different route of administration, pulmonary delivery has unique benefits such as circumvents first pass hepatic metabolism and reduces dose and side effects.

RESULTS

Respiratory disorders pose a major threat to the morbidity and mortality to public health globally. Pulmonary delivery can be achieved through various drug delivery devices such as nebulizers, dry powder inhalers, and metered dose inhalers. Among them, metered dose inhalers are the most interesting and first choice of clinician over others. This review focused on nanotechnology based pulmonary drug delivery using metered dose inhalers. This report focused on delivery of various types of therapeutics using nanocarriers such as polymeric nanoparticles and micelles, dendrimers, lipid nanocarriers such as liposomes, solid lipid nanostructures and nanostructured lipid carriers, and other using metered dose inhalers discussed comprehensively. This report provides insight about the effect of parameters of MDI such as co-solvent, propellants, actuators shape, nozzle diameters, and jet lengths, and respiratory flow rate, and particle size of co-suspension of drug on aerodynamics and lung deposition of formulation. This review also provided the insight about various metered dose inhalers market scenario and digital metered dose inhalers.

CONCLUSION

This report concluded the clinical potential of metered dose inhalers, summary of current progress and future perspectives towards the smart digital metered dose inhalers development.

Dexamethasone: Insights into Pharmacological Aspects, Therapeutic Mechanisms, and Delivery Systems

Dexamethasone (DEX) has been widely used to treat a variety of diseases, including autoimmune diseases, allergies, ocular disorders, cancer, and, more recently, COVID-19. However, DEX usage is often restricted in the clinic due to its poor water solubility. When administered through a systemic route, it can elicit severe side effects, such as hypertension, peptic ulcers, hyperglycemia, and hydro-electrolytic disorders. There is currently much interest in developing efficient DEX-loaded nanoformulations that ameliorate adverse disease effects inhibiting advancements in scientific research. Various nanoparticles have been developed to selectively deliver drugs without destroying healthy cells or organs in recent years. In the present review, we have summarized some of the most attractive applications of DEX-loaded delivery systems, including liposomes, polymers, hydrogels, nanofibers, silica, calcium phosphate, and hydroxyapatite. This review provides our readers with a broad spectrum of nanomedicine approaches to deliver DEX safely.

Preparation, in vitro and in vivo Evaluation of Thermosensitive in situ Gel Loaded with Ibuprofen-Solid Lipid Nanoparticles for Rectal Delivery

Background

Ibuprofen (IBU), a nonsteroidal anti-inflammatory drug, shows poor gastrointestinal absorption due to its low solubility, which limits its clinical application.

Objective

In the present study, we aimed to develop thermosensitive gel-mediated ibuprofen-solid lipid nanoparticles (IBU-SLN-ISG) to improve the dissolution and bioavailability of IBU after rectal delivery.

Methods

IBU-loaded SLNs (IBU-SLNs) were developed and optimized applying Box-Behnken design. The optimized IBU-SLNs were characterized by physicochemical parameters and morphology. Then, the optimized IBU-SLNs was incorporated into the gel and characterized for gel properties and rheology and investigated its release in vitro, pharmacokinetics in vivo, rectal irritation and rectal retention time.

Results

The optimized SLNs had an EE of 90.74 ± 1.40%, DL of 11.36 ± 1.20%, MPS of 166.77 ± 2.26 nm, PDI of 0.27 ± 0.08, and ZP of −21.00 ± 0.59 mV. The FTIR spectra confirmed successful encapsulation of the drug inside the nanoparticle as only peaks responsible for the lipid could be identified. This corroborated well with XRD spectra, which showed a completely amorphous state of the IBU-SLNs as compared to the crystalline nature of the pure drug. The gelation temperature of the prepared IBU-SLN-ISG was 33.30 ± 0.78°C, the gelation time was 14.67 ± 2.52 s, the gel strength was 54.00 ± 1.41 s, and the mucoadhesion was (11.54±0.37) × 10²dyne/cm². The in vitro results of IBU-SLNs and IBU-SLN-ISG showed a biphasic release pattern with initial burst release followed by sustained release. More importantly, IBU-SLN-ISG produced much better absorption of IBU and improved bioavailability in rats. In addition, IBU-SLN-ISG caused no irritation or damage to rectal tissues, and could be retained in the rectum for a long time.

Conclusion

Thermosensitive in situ gel loaded with IBU-solid lipid nanoparticles might be further developed as a more convenient and effective rectal dosage form.

Fabrication and Assessment of Diosgenin Encapsulated Stearic Acid Solid Lipid Nanoparticles for Its Anticancer and Antidepressant Effects Using in vitro and in vivo Models

Inflammatory cascade plays a pivotal role in the onset and progression of major depressive disorder (MDD) and glioblastoma multiforme (GBM). Therefore, questing natural compounds with anti-inflammatory activity such as diosgenin can act as a double-edged sword targeting cancer and cancer-induced inflammation simultaneously. The blood–brain barrier limits the therapeutic efficiency of the drugs against intracranial pathologies including depression and brain cancers. Encapsulating a drug molecule in lipid nanoparticles can overcome this obstacle. The current study has thus investigated the anticancer and antidepressant effect of Tween 80 (P80) coated stearic acid solid lipid nanoparticles (SLNPs) encapsulating the diosgenin. Physio-chemical characterizations of SLNPs were performed to assess their stability, monodispersity, and entrapment efficiency. In vitro cytotoxic analysis of naked and drug encapsulated SLNPs on U-87 cell line indicated diosgenin IC₅₀ value to be 194.4 μM, while diosgenin encapsulation in nanoparticles slightly decreases the toxicity. Antidepressant effects of encapsulated and non-encapsulated diosgenin were comprehensively evaluated in the concanavalin-A–induced sickness behavior mouse model. Behavior test results indicate that diosgenin and diosgenin encapsulated nanoparticles significantly alleviated anxiety-like and depressive behavior. Diosgenin incorporated SLNPs also improved grooming behavior and social interaction as well as showed normal levels of neutrophils and leukocytes with no toxicity indication. In conclusion, diosgenin and diosgenin encapsulated solid lipid nanoparticles proved successful in decreasing in vitro cancer cell proliferation and improving sickness behavioral phenotype and thus merit further exploration.

Formulation design, production and characterisation of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) for the encapsulation of a model hydrophobic active

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Lipid materials were chosen based on theoretical and experimental lipid screening.

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SLNs and NLCs with high curcumin loading were produced using the selected lipids.

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Nano-sized lipid particles fabricated by tuning the processing parameters.

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Lipid matrix component compatibility affects thermal properties as shown by DSC.

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Formation of distinct lipid structures in liquid lipid concentration-dependent manner.

Lipid nanoparticles have been widely investigated for their use as either carriers for poorly water soluble actives or as (Pickering) emulsion stabilisers. Recent studies have suggested that the fabrication of lipid nanostructures that can display both these performances concurrently, can enable the development of liquid formulations for multi-active encapsulation and release. Understanding the effects of different formulation variables on the microstructural attributes that underline both these functionalities is crucial in developing such lipid nanostructures. In this study, two types of lipid-based nanoparticles, solid lipid nanoparticles and nanostructured lipid carriers, were fabricated using varying formulation parameters, namely type of solid lipid, concentration of liquid lipid and type/concentration of surface active species. The impact of these formulation parameters on the size, thermal properties, encapsulation efficiency, loading capacity and long-term storage stability of the developed lipid systems, was studied. Preliminary lipid screening and processing conditions studies, focused on creating a suitable lipid host matrix of appropriate dimensions that could enable the high loading of a model hydrophobic active (curcumin). Informed by this, selected lipid nanostructures were then produced. These were characterised by encapsulation efficiency and loading capacity values as high as 99% and 5%, respectively, and particle dimensions within the desirable size range (100-200 nm) required to enable Pickering functionality. Compatibility between the lipid matrix components, and liquid lipid/active addition were shown to greatly influence the polymorphism/crystallinity of the fabricated particles, with the latter demonstrating a liquid lipid concentration-dependent behaviour. Successful long-term storage stability of up to 28 weeks was confirmed for certain formulations.

Formulation and Pathohistological Study of Mizolastine-Solid Lipid Nanoparticles-Loaded Ocular Hydrogels

Background

Mizolastine (MZL) is a dual-action nonsedating topical antihistamine anti-inflammatory agent that is used to relieve allergic conditions, such as rhinitis and conjunctivitis. Solid lipid nanoparticles (SLNs) are advanced delivery system in ophthalmology, with the merits of increasing the corneal drug absorption and hence improved bioavailability with the objective of ocular drug targeting.

Methods

First, MZL was formulated as MZL-SLNs by hot homogenization/ultrasonication adopting a 3² full factorial design. Solid-state characterization, in vitro release, and stability studies have been performed. Then, the optimized MZL-SLNs formula has been incorporated into ocular hydrogels using 1.5% w/v Na alginate and 5% w/v polyvinylpyrrolidone K₉₀. The gels were evaluated via in vitro release as well as in vivo studies by applying allergic conjunctivitis congestion in a rabbit-eye model.

Results

The optimized formula (F4) was characterized by the highest entrapment efficiency (86.5±1.47%), the smallest mean particle size (202.3±13.59 nm), and reasonable zeta potential (−22.03±3.65 mV). Solid-state characterization of the encapsulation of MZL in SLNs was undertaken. In vitro results showed a sustained release profile from MZL-SLNs up to 30 hours with a non-Fickian Higuchi kinetic model. Stability studies confirmed immutability of freeze-dried MZL-SLNs (F4) upon storage for 6 months. Finally, hydrogel formulations containing MZL-SLNs, proved ocular congestion disappearance with completely repaired conjunctiva after 24 hours. Moreover, pretreatment with MZL-SLNs–loaded hydrogel imparted markedly decreased TNF-α and VEGF-expression levels in rabbits conjunctivae compared with post-treatment with the same formula.

Conclusion

MZL-SLNs could be considered a promising stable sustained-release nanoparticulate system for preparing ocular hydrogel as effective antiallergy ocular delivery systems.

Development of ritonavir-loaded nanostructured lipid carriers employing quality by design (QbD) as a tool: characterizations, permeability, and bioavailability studies

The objective of the present work was to optimize ritonavir (RTV)-loaded nanostructured lipid carriers (NLCs) to improve bioavailability using a quality by design (QbD)-based technique. Risk assessment was studied using "cause and effect" diagram followed by failure mode effect analysis (FMEA) to identify the effective high-risk variables for the formulation development. Quality target product profile (QTPP) and critical quality attributes (CQAs) were initially assigned for the proposed product. Central composite rotatable design (CCRD) was used to identify the individual and combined interactions of formulation variables. RTV-loaded NLC (RTV-NLC) was prepared using emulsification-ultrasonication method. The effect of formulation variables like ultrasound amplitude, lipid concentration, surfactant concentration on their responses like particle size, polydispersity index (PDI), and entrapment efficiency (EE) were studied by CCRD. The optimized formulation was subjected to lyophilization to obtain dry NLCs for solid-state analysis. DSC and PXRD investigations showed that RTV was molecularly dispersed in lipid matrix indicating amorphous form present in the formulation. FESEM and AFM depicted the spherical and uniform particles. The increase in solubility and dissolution rate is expected to be related to the molecular dispersion, amorphous state, of the drug in the nanoparticle. The optimized NLCs showed good physical stability during storage for 6 months. RTV-NLC was further subjected to in vitro studies and found a successful sustained release rate of 92.37 ± 1.03%. The parallel artificial membrane permeability assay (PAMPA) and everted gut sac model have demonstrated the permeation enhancement of RTV. In vivo study observed the enhanced bioavailability with 2.86-fold suggesting optimized NLC successfully overcome the issue of solubility.

Brain-targeted, drug-loaded solid lipid nanoparticles against glioblastoma cells in culture

The aim of this study was the preparation of solid lipid nanoparticles (SLN) formed from cetyl palmitate with having targeting molecules for monocarboxylate transporter-1 (MCT-1): β-hydroxybutyric acid and anticancer agents: carmustine (BCNU) and temozolomide (TMZ) for enhanced anti-proliferation against glioblastoma multiforme (GBM). Properties including size, morphology, chemical structure, zeta potential, drug encapsulation efficacy, drug release, biocompatibility, stability were determined, and in vitro studies were done. BCNU and TMZ loaded SLNs had a hydrodynamic size of 227 nm ± 46 a zeta potential of -25 mV ± 4 with biocompatible features. The data showed rapid drug release at first and then continuous release. Nanoparticles could be stored for nine months. BCNU and TMZ loaded SLNs exhibited a remarkable increment in the antitumor activity compared to the free-drugs and induced apoptosis on U87MG cells. In addition, targeted nanoparticles were more uptaken by MCT-1 expressing brain cells. This study indicated that BCNU and TMZ loaded SLNs could act as a useful anticancer system for targeted GBM therapy.

Quality by design (QbD)-based fabrication of atazanavir-loaded nanostructured lipid carriers for lymph targeting: bioavailability enhancement using chylomicron flow block model and toxicity studies

Atazanavir (ATV) is widely used as anti-HIV agent having poor aqueous solubility needs to modulate novel drug delivery system to enhance therapeutic efficiency and safety. The main objective of the present work was to fabricate ATV-loaded nanostructured lipid carriers (NLCs) employing quality by design (QbD) approach to address the challenges of bioavailability and their safety after oral administration. Herein, the main objective was to identify the influencing variables for the production of quality products. Considering this objective, quality target product profile (QTPP) was assigned and a systematic risk assessment study was performed to identify the critical material attributes (CMAs) and critical process parameter (CPP) having an influence on critical quality attributes (CQAs). Lipid concentrations, surfactant concentrations, and pressure of high-pressure homogenizer were identified as CMAs and CPP. ATV-NLCs were prepared by emulsification-high pressure homogenization method and further lyophilized to obtain solid-state NLCs. The effect of formulation variables (CMAs and CPP) on responses like particle size (Y₁), polydispersity index (Y₂), and zeta potential (Y₃) was observed by central composite rotatable design (CCRD). The data were statistically evaluated by ANOVA for confirmation of a significant level (p < 0.05). The optimal conditions of NLCs were obtained by generating design space and desirability value. The lyophilized ATV-NLCs were characterized by DSC, powder X-ray diffraction, and FT-IR analysis. The morphology of NLCs was revealed by TEM and FESEM. In vitro study suggested a sustained release pattern of drug (92.37 ± 1.03%) with a mechanism of Korsmeyer-Peppas model (r² = 0.925, and n = 0.63). In vivo evaluation in Wistar rats showed significantly higher (p < 0.001) plasma drug concentration of ATV-NLCs as compared to ATV-suspension using chylomicron flow block model. The relative bioavailability of ATV-NLCs was obtained to be 2.54 folds. Thus, a safe and promising drug targeting system was successfully developed to improve bioavailability and avoiding first-pass effect ensures to circumvent the acute-toxicity of liver.

Development and Characterization of Stingless Bee Propolis Properties for the Development of Solid Lipid Nanoparticles for Loading Lipophilic Substances

Stingless bees are insects which are popularly bred by agriculturists in the eastern region of Thailand for the pollination of their orchards. The products from stingless bee breeding include bee honey and bee propolis. The objective of this experiment is to study the possibility of developing stingless bee propolis wax into solid lipid nanoparticles (SLN) by the comparison of five surfactants (Brij 721, Cremophor WO 7, Myrj 52, Poloxamer 188, and Tween 80). Each surfactant is used at three concentrations: 10%, 20%, and 30%. A master formula is selected according to the following: physical features, particle size, zeta potential, and entrapment. The results showed that Brij 721 and Myri 52 at 20% can be used in preparing SLN and have good preservation properties for vitamin E (size: 451.2 nm and 416.8 nm, zeta potential: - 24.0 and - 32.7; % EE: 92.32% and 92.00%, resp.). Therefore, they are further developed by adding the following drugs at low solubility: curcumin, ibuprofen, and astaxanthin. It is found that a formula using the surfactants Brij 721 and Myrj 52 at 20% have similar drug entrapment. The entrapment study involves curcumin 82%, ibuprofen 40%, and astaxanthin 67%. Moreover, the cytotoxicity test of blank solid lipid nanoparticle found no toxicty in fibroblast cell line (CRL-2522). Therefore, from this study, it is determined that stingless bee propolis wax has the potential to be developed to provide more efficient SLN in the future.

Solid Lipid Nanoparticles Produced via a Coacervation Method as Promising Carriers for Controlled Release of Quercetin

Quercetin is a poorly water-soluble flavonoid with many benefits to human health. Besides the natural food resources that may provide Quercetin, the interest in delivery systems that could enhance its bioavailability in the human body has seen growth in recent years. Promising delivery system candidates are represented by Solid Lipid Nanoparticles (SLNs) which are composed of well-tolerated compounds and provide a relatively high encapsulation efficiency and suitable controlled release. In this study, Quercetin-loaded and negatively charged Solid Lipid Nanoparticles were synthesized based on a coacervation method, using stearic acid as a core lipid and Arabic Gum as a stabilizer. Samples were qualitatively characterized by Dynamic light scattering (DLS), Zeta Potential, Surface infrared spectroscopy (FTIR-ATR), and Time of flight secondary ion mass spectrometry (ToF-SIMS). Encapsulation efficiency, drug release, and antioxidant effect against ABTS•+ were evaluated in vitro by UV-VIS spectrophotometry.

Lignin: Drug/Gene Delivery and Tissue Engineering Applications

Lignin is an abundant renewable natural biopolymer. Moreover, a significant development in lignin pretreatment and processing technologies has opened a new window to explore lignin and lignin-based bionanomaterials. In the last decade, lignin has been widely explored in different applications such as drug and gene delivery, tissue engineering, food science, water purification, biofuels, environmental, pharmaceuticals, nutraceutical, catalysis, and other interesting low-value-added energy applications. The complex nature and antioxidant, antimicrobial, and biocompatibility of lignin attracted its use in various biomedical applications because of ease of functionalization, availability of diverse functional sites, tunable physicochemical and mechanical properties. In addition to it, its diverse properties such as reactivity towards oxygen radical, metal chelation, renewable nature, biodegradability, favorable interaction with cells, nature to mimic the extracellular environment, and ease of nanoparticles preparation make it a very interesting material for biomedical use. Tremendous progress has been made in drug delivery and tissue engineering in recent years. However, still, it remains challenging to identify an ideal and compatible nanomaterial for biomedical applications. In this review, recent progress of lignin towards biomedical applications especially in drug delivery and in tissue engineering along with challenges, future possibilities have been comprehensively reviewed.

Rutin-Loaded Solid Lipid Nanoparticles: Characterization and In Vitro Evaluation

This study was aimed at preparing and characterizing solid lipid nanoparticles loading rutin (RT-SLNs) for the treatment of oxidative stress-induced diseases. Phospholipon 80H® as a solid lipid and Polysorbate 80 as surfactant were used for the SLNs preparation, using the solvent emulsification/diffusion method. We obtained spherical RT-SLNs with low sizes, ranging from 40 to 60 nm (hydrodynamic radius) for the SLNs prepared starting from 2% and 5% (w/w) theoretical amount. All prepared formulations showed negative zeta-potential values. RT was efficiently encapsulated within SLNs, obtaining high encapsulation efficiency and drug content percentages, particularly for SLNs prepared with a 5% theoretical amount of RT. In vitro release profiles and analysis of the obtained data applying different kinetic models revealed Fickian diffusion as the main mechanism of RT release from the SLNs. The morphology of RT-SLNs was characterized by scanning electron microscopy (SEM), whereas the interactions between RT and the lipid matrix were investigated by Raman spectroscopy, evidencing spectral modifications of characteristic bands of RT due to the establishment of new interactions. Finally, antioxidant activity assay on human glioblastoma astrocytoma (U373) culture cells showed a dose-dependent activity for RT-SLNs, particularly at the highest assayed dose (50 μM), whereas the free drug showed the lesser activity.

Characterization and Systemic Delivery of Dibenzoylmethane via the Intranasal Route

Intranasal (IN) administration is known to be noninvasive with the potential to carry a drug or vaccine directly to the blood, bypassing first-pass metabolism in the liver and the harsh environment of the gastrointestinal system. Orally administered dibenzoylmethane (DBM) has been shown experimentally to be neuroprotective in animal models of tauopathy and prion disease and effective in the treatment of certain forms of cancers. The purpose of this study was to prepare, characterize, and test formulations of DBM designed for IN administration. DBM was formulated in brain homogenate (BH) and hypromellose and as nanoparticles (NPs). These formulations were detected using UPLC and characterized in solid and suspension states; NPs were also characterized by in vitro cell culture-based studies. Particle size for DBM NP was 163.8 ± 3.2 nm, and in vitro release studies showed 95.80% of DBM was released from the NPs within 8 days. In vitro cell, culture studies suggested no drug uptake until 6 h. A histological analysis of nasal cavity (NC) sections and blood detection studies were carried out 30 min after inhalation. DBM amounting to 40.77 ± 4.93 and 44.45 ± 5.36 ng/mL was detected in the blood of animals administered DBM in polymeric and NP formulation, respectively. Histological studies on NCs confirmed the presence of BH within lymphatic vessels in the lamina propria of each animal; BH was identified traversing the mucosa in 2 animals. Thus, formulations for DBM administered via IN route were successfully designed and characterized and able to cross the nasal mucosa following inhalation.

Chronic Inflammatory Diseases, Anti-Inflammatory Agents and Their Delivery Nanosystems

Inflammatory diseases, whether caused by excessive stress on certain tissues/parts of the body or arising from infections accompanying autoimmune or secondary diseases, have become a problem, especially in the Western world today. Whether these are inflammations of visceral organs, joints, bones, or the like, they are always a physiological reaction of the body, which always tries to eradicate noxious agents and restore tissue homeostasis. Unfortunately, this often results in damage, often irreversible, to the affected tissues. Nevertheless, these inflammatory reactions of the body are the results of excessive stress, strain, and the generally unhealthy environment, in which the people of Western civilization live. The pathophysiology and pathobiochemistry of inflammatory/autoimmune processes are being studied in deep detail, and pharmaceutical companies are constantly developing new drugs that modulate/suppress inflammatory responses and endogenous pro-inflammatory agents. In addition to new specifically targeted drugs for a variety of pro-inflammatory agents, a strategy can be found for the use of older drugs, which are formulated into special nanodrug delivery systems with targeted distribution and often modified release. This contribution summarizes the current state of research and development of nanoformulated anti-inflammatory agents from both conventional drug classes and experimental drugs or dietary supplements used to alleviate inflammatory reactions.

Design of Non-Haemolytic Nanoemulsions for Intravenous Administration of Hydrophobic APIs

Among advanced formulation strategies, nanoemulsions are considered useful drug-delivery systems allowing to improve the solubility and the bioavailability of lipophilic drugs. To select safe excipients for nanoemulsion formulation and to discard any haemolytic potential, an in vitro miniaturized test was performed on human whole blood. From haemolysis results obtained on eighteen of the most commonly used excipients, a medium chain triglyceride, a surfactant, and a solubilizer were selected for formulation assays. Based on a design of experiments and a ternary diagram, the feasibility of nanoemulsions was determined. The composition was defined to produce monodisperse nanodroplets with a diameter of either 50 or 120 nm, and their physicochemical properties were optimized to be suitable for intravenous administration. These nanoemulsions, stable over 21 days in storage conditions, were shown to be able to encapsulate with high encapsulation efficiency and high drug loading, up to 16% (w/w), two water practically insoluble drug models: ibuprofen and fenofibrate. Both drugs may be released according to a modulable profile in sink conditions. Such nanoemulsions appear as a very promising and attractive strategy for the efficient early preclinical development of hydrophobic drugs.

Core-shell nanostructures: perspectives towards drug delivery applications

Nanosystems have shown encouraging outcomes and substantial progress in the areas of drug delivery and biomedical applications. However, the controlled and targeted delivery of drugs or genes can be limited due to their physicochemical and functional properties. In this regard, core-shell type nanoparticles are promising nanocarrier systems for controlled and targeted drug delivery applications. These functional nanoparticles are emerging as a particular class of nanosystems because of their unique advantages, including high surface area, and easy surface modification and functionalization. Such unique advantages can facilitate the use of core-shell nanoparticles for the selective mingling of two or more different functional properties in a single nanosystem to achieve the desired physicochemical properties that are essential for effective targeted drug delivery. Several types of core-shell nanoparticles, such as metallic, magnetic, silica-based, upconversion, and carbon-based core-shell nanoparticles, have been designed and developed for drug delivery applications. Keeping the scope, demand, and challenges in view, the present review explores state-of-the-art developments and advances in core-shell nanoparticle systems, the desired structure-property relationships, newly generated properties, the effects of parameter control, surface modification, and functionalization, and, last but not least, their promising applications in the fields of drug delivery, biomedical applications, and tissue engineering. This review also supports significant future research for developing multi-core and shell-based functional nanosystems to investigate nano-therapies that are needed for advanced, precise, and personalized healthcare systems.

Nanotechnology for angiogenesis: opportunities and challenges

Angiogenesis plays a critical role within the human body, from the early stages of life (i.e., embryonic development) to life-threatening diseases (e.g., cancer, heart attack, stroke, wound healing). Many pharmaceutical companies have expended huge efforts on both stimulation and inhibition of angiogenesis. During the last decade, the nanotechnology revolution has made a great impact in medicine, and regulatory approvals are starting to be achieved for nanomedicines to treat a wide range of diseases. Angiogenesis therapies involve the inhibition of angiogenesis in oncology and ophthalmology, and stimulation of angiogenesis in wound healing and tissue engineering. This review aims to summarize nanotechnology-based strategies that have been explored in the broad area of angiogenesis. Lipid-based, carbon-based and polymeric nanoparticles, and a wide range of inorganic and metallic nanoparticles are covered in detail. Theranostic and imaging approaches can be facilitated by nanoparticles. Many preparations have been reported to have a bimodal effect where they stimulate angiogenesis at low dose and inhibit it at higher doses.

Sonochemical synthesis of carbon dots, mechanism, effect of parameters, and catalytic, energy, biomedical and tissue engineering applications

Carbon-based nanomaterials are gaining more and more interest because of their wide range of applications. Carbon dots (CDs) have shown exclusive interest due to unique and novel physicochemical, optical, electrical, and biological properties. Since their discovery, CDs became a promising material for wide range of research applications from energy to biomedical and tissue engineering applications. At same time several new methods have been developed for the synthesis of CDs. Compared to many of these methods, the sonochemical preparation is a green method with advantages such as facile, mild experimental conditions, green energy sources, and feasibility to formulate CDs and doped CDs with controlled physicochemical properties and lower toxicity. In the last five years, the sonochemically synthesized CDs were extensively studied in a wide range of applications. In this review, we discussed the sonochemical assisted synthesis of CDs, doped CDs and their nanocomposites. In addition to the synthetic route, we will discuss the effect of various experimental parameters on the physicochemical properties of CDs; and their applications in different research areas such as bioimaging, drug delivery, catalysis, antibacterial, polymerization, neural tissue engineering, dye absorption, ointments, electronic devices, lithium ion batteries, and supercapacitors. This review concludes with further research directions to be explored for the applications of sonochemical synthesized CDs.

Shape Matters: Comprehensive Analysis of Star-Shaped Lipid Nanoparticles

The research of lipid nanoparticles (LNPs) has been ongoing for more than three decades, and more research are still being carried out today. Being the first Food and Drug Administration (FDA)-approved nanomedicine, LNPs not only provide various advantages, but also display some unique properties. The unique lipid bilayer structure of LNPs allows it to encapsulate both fat-soluble and water-soluble molecules, hence enabling a wide range of possibilities for the delivery of therapeutic agents with different physical and chemical properties. The ultra-small size of some LNPs confers them the ability to cross the blood brain barrier (BBB), thus obtaining superiority in the treatment of diseases of the central nervous system (CNS). The ability of tumor targeting is one of the basic requirements to be an excellent delivery system, where the LNPs have to reach the interior of the tumor. Factors that influence tumor extravasation and the permeability of LNPs are size, surface charge, lipid composition, and shape. The effect of size, surface charge, and lipid composition on the cellular uptake of LNPs is no longer recent news, while increasing numbers of researchers are interested in the effect of shape on the uptake of LNPs and its consequential effects. In our study, we prepared three lipid nanostars (LNSs) by mixing phosphatidylcholine (PC) with different backbone lengths (C14:C4 or C16:C6 or C18:C8) at a 3:1 ratio. Although several star-shaped nanocarriers have been reported, these are the first reported star-shaped LNPs. These LNSs were proven to be safe, similar in size with their spherical controls (~100 nm), and stable at 37°C. The release rate of these LNSs are inversely related to the length of the lipid backbone. Most importantly, these LNSs exhibited greatly enhanced cellular uptake and in vivo tumor extravasation compared with their spherical controls. Based on the different uptake and pharmacokinetic characteristics displayed by these LNSs, numerous route formulations could be taken into consideration, such as via injection or transdermal patch. Due to their excellent cellular uptake and in vivo tumor accumulation, these LNSs show exciting potential for application in cancer therapy.