Solid lipid nanoparticles

Cyclodextrin-Modified Nanomaterials for Drug Delivery: Classification and Advances in Controlled Release and Bioavailability

In drug delivery, one widely used way of overcoming the biopharmaceutical problems present in several active pharmaceutical ingredients, such as poor aqueous solubility, early instability, and low bioavailability, is the formation of inclusion compounds with cyclodextrins (CD). In recent years, the use of CD derivatives in combination with nanomaterials has shown to be a promising strategy for formulating new, optimized systems. The goals of this review are to give in-depth knowledge and critical appraisal of the main CD-modified or CD-based nanomaterials for drug delivery, such as lipid-based nanocarriers, natural and synthetic polymeric nanocarriers, nanosponges, graphene derivatives, mesoporous silica nanoparticles, plasmonic and magnetic nanoparticles, quantum dots and other miscellaneous systems such as nanovalves, metal-organic frameworks, Janus nanoparticles, and nanofibers. Special attention is given to nanosystems that achieve controlled drug release and increase their bioavailability during in vivo studies.

Solid lipid nanoparticles and nanoemulsions with solid shell: Physical and thermal stability

HYPOTHESIS

Nanoemulsions (NE) and solid lipid nanoparticles (SLN) used for drug delivery should have a solid shell to be stable during long shelf life and become liquid at human body temperature. The core components of lipid nanoparticles can be partially incorporated into the shell and affect the physical and thermal stability.

EXPERIMENTS

We prepared NE and SLN by the phase inversion temperature (PIT) method. Solidification of the surfactants Tween60 and Span 60 on the surface of NE droplets with paraffin oil resulted in the formation of the solid shell. SLN contained stearic acid in the core and the same surfactants in the solid shell. The size, structure and stability of the NE and SLN were studied by DLS and cryo-TEM. Their crystallization and melting were analyzed using DSC.

FINDINGS

The lipid nanoparticles were resistant to aggregation and sedimentation and hold up to at least two cycles of heating to 50-60 °C and subsequent cooling to 5 °C, even though the upper temperatures were higher than the melting point of the surfactant shell. The expected liquid core/solid shell morphology of NE was confirmed. SLN were composed of a semi-liquid core of supercooled stearic acid melt and coated with a solid surfactant shell, so they can be treated as NE. Stearic acid molecules penetrated the shell, leading to an increase in its melting point.

Influence of process and formulation parameters on the preparation of solid lipid nanoparticles by dual centrifugation

A promising strategy to formulate poorly water-soluble active pharmaceutical ingredients (APIs) is the application of these substances in solid lipid nanoparticles. These drug carrier systems are commonly prepared by high-pressure homogenization above the melting temperature of the utilized lipid. While being very useful for large-scale production this method is quite resource-consuming and does not allow simultaneous processing of multiple samples, e.g. for screening purposes. For this reason, an alternative manufacturing process, dual centrifugation, is introduced to prepare solid lipid nanoparticles. The ingredients of the dispersions were directly weighed into 2 mL vessels at room temperature without the need to prepare a pre-mix emulsion. Due to an additional rotation of the samples in the heated centrifuge as well as the addition of grinding media an intensive stressing of the samples was achieved. The emulsification process was finished within 10 min with sample temperatures of up to 90 °C being obtained. Dependent on the process set-up like grinding media size, filling ratio or process temperature and the composition of the lipid formulation, the achieved particles sizes were below 200 nm and had a narrow, monomodal size distribution.

Emerging nanoformulation strategies for phytocompounds and applications from drug delivery to phototherapy to imaging

Over thousands of years, natural bioactive compounds derived from plants (bioactive phytocompounds, BPCs) have been used worldwide to address human health issues. Today, they are a significant resource for drug discovery in the development of modern medicines. Although many BPCs have promising biological activities, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations of low solubility, structural instability, short half-life, poor bioavailability, and non-specific distribution to organs. Researchers have utilized emerging nanoformulation (NF) technologies to overcome these limitations as they have demonstrated great potential to improve the solubility, stability, and pharmacokinetic and pharmacodynamic characteristics of BPCs. This review exemplifies NF strategies for resolving the issues associated with BPCs and summarizes recent advances in their preclinical and clinical applications for imaging and therapy. This review also highlights how innovative NF technologies play a leading role in next-generation BPC-based drug development for extended therapeutic applications. Finally, this review discusses the opportunities to take BPCs with meaningful clinical impact from bench to bedside and extend the patent life of BPC-based medicines with new formulations or application to new adjacent diseases beyond the primary drug indications.

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Natural bioactive phytocompounds derived from plants have been used worldwide to address human health issues. However, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations.

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Nanoformulation approach has recently been underlined as an emerging pharmaceutical strategy to overcome the intrinsic drawbacks of bioactive phytocompounds.

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Various types of nanoformulation and their up-to-date applications for targeted delivery, phototherapy, and imaging are reviewed. Finally, their clinical implications for the repurposing of bioactive phytocompounds are deliberated.

Engineering Nano- and Microparticles as Oral Delivery Vehicles to Promote Intestinal Lymphatic Drug Transport

Targeted oral delivery of a drug via the intestinal lymphatic system (ILS) has the advantages of protecting against hepatic first-pass metabolism of the drug and improving its pharmacokinetic performance. It is also a promising route for the oral delivery of vaccines and therapeutic agents to induce mucosal immune responses and treat lymphatic diseases, respectively. This article describes the anatomical structures and physiological characteristics of the ILS, with an emphasis on enterocytes and microfold (M) cells, which are the main gateways for the transport of particulate delivery vehicles across the intestinal epithelium into the lymphatics. A comprehensive overview of recent advances in the rational engineering of particulate vehicles, along with the challenges and opportunities that they present for improving ILS drug delivery, is provided, and the mechanisms by which such vehicles target and transport through enterocytes or M cells are discussed. The use of naturally sourced materials, such as yeast microcapsules and their derived polymeric β-glucans, as novel ILS-targeting delivery vehicles is also reviewed. Such use is the focus of an emerging field of research. Their potential use in the oral delivery of nucleic acids, such as mRNA vaccines, is proposed.

Dually Cross-Linked Core-Shell Structure Nanohydrogel with Redox-Responsive Degradability for Intracellular Delivery

A redox-responsive nanocarrier is a promising strategy for the intracellular drug release because it protects the payload, prevents its undesirable leakage during extracellular transport, and favors site-specific drug delivery. In this study, we developed a novel redox responsive core-shell structure nanohydrogel prepared by a water in oil nanoemulsion method using two biocompatible synthetic polymers: vinyl sulfonated poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate)-polyethylene glycol-poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate) triblock copolymer, and thiolated hyaluronic acid. The influence on the nanohydrogel particle size and distribution of formulation parameters was investigated by a three-level full factorial design to optimize the preparation conditions. The surface and core-shell morphology of the nanohydrogel were observed by scanning electron microscope, transmission electron microscopy, and further confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy from the standpoint of chemical composition. The redox-responsive biodegradability of the nanohydrogel in reducing environments was determined using glutathione as reducing agent. A nanohydrogel with particle size around 250 nm and polydispersity index around 0.1 is characterized by a thermosensitive shell which jellifies at body temperature and crosslinks at the interface of a redox-responsive hyaluronic acid core via the Michael addition reaction. The nanohydrogel showed good encapsulation efficiency for model macromolecules of different molecular weight (93% for cytochrome C, 47% for horseradish peroxidase, and 90% for bovine serum albumin), capacity to retain the peroxidase-like enzymatic activity (around 90%) of cytochrome C and horseradish peroxidase, and specific redox-responsive release behavior. Additionally, the nanohydrogel exhibited excellent cytocompatibility and internalization efficiency into macrophages. Therefore, the developed core-shell structure nanohydrogel can be considered a promising tool for the potential intracellular delivery of different pharmaceutical applications, including for cancer therapy.

Application of Lipid-Based Nanocarriers for Antitubercular Drug Delivery: A Review

The antimicrobial drugs currently used for the management of tuberculosis (TB) exhibit poor bioavailability that necessitates prolonged treatment regimens and high dosing frequency to achieve optimal therapeutic outcomes. In addition, these agents cause severe adverse effects, as well as having detrimental interactions with other drugs used in the treatment of comorbid conditions such as HIV/AIDS. The challenges associated with the current TB regimens contribute to low levels of patient adherence and, consequently, the development of multidrug-resistant TB strains. This has led to the urgent need to develop newer drug delivery systems to improve the treatment of TB. Targeted drug delivery systems provide higher drug concentrations at the infection site, thus leading to reduced incidences of adverse effects. Lipid-based nanocarriers have proven to be effective in improving the solubility and bioavailability of antimicrobials whilst decreasing the incidence of adverse effects through targeted delivery. The potential application of lipid-based carriers such as liposomes, niosomes, solid lipid nanoparticles, nanostructured lipid carriers, nano and microemulsions, and self-emulsifying drug delivery systems for the treatment of TB is reviewed herein. The composition of the investigated lipid-based carriers, their characteristics, and their influence on bioavailability, toxicity, and sustained drug delivery are also discussed. Overall, lipid-based systems have shown great promise in anti-TB drug delivery applications. The summary of the reviewed data encourages future efforts to boost the translational development of lipid-based nanocarriers to improve TB therapy.

Photoprotection and Photostability of a New Lignin-Gelatin-Baccharis antioquensis-Based Hybrid Biomaterial

The aim of this study was to develop a new hybrid biomaterial that could photo-stabilize and improve the photoprotective capacity of a Baccharis antioquensis extract. Different combinations of lignin/gelatin/natural extract were applied to prepare hybrid biomaterial nanoparticles (NPs), which were then incorporated into an emulsion. The in vitro photoprotection and photostability were evaluated. The methanolic extract showed high phenolic content (646.4 ± 9.5 mg GAE/g dry extract) and a DPPH radical assay revealed that the antiradical capacity of the extract (0.13 to 0.05 g extract/mmol DPPH) was even better than that of BHT. The particle size of the hybrid biomaterial ranged from 100 to 255 nm; a polydispersity index (PdI) between 0.416 and 0.788 is suitable for topical use in dermocosmetic products. The loading capacity of the extract ranged from 27.0 to 44.5%, and the nanoparticles (NPs) showed electrostatic stability in accordance with the zeta potential value. We found that the formulation based on lignin: extract (1:1 ratio) and gelatin: lignin: extract (0.5:0.5:1 ratio) demonstrated photoprotection qualities with a sun protection factor (SPF) ranging from 9.4 to 22.6. In addition, all the hybrid NP-formulations were time-stable with %SPFeff and %UVAPFeff greater than 80% after exposure to 2 h of radiation. These results suggest that the hybrid biopolymer-natural extract improved the photoprotection and photostability properties, as well as the antiradical capacity, of the B. antioquensis extract, and may be useful for trapping high polyphenol content from natural extracts, with potential application in cosmeceutical formulations.

Determination of lipid content and stability in lipid nanoparticles using ultra high-performance liquid chromatography in combination with a Corona Charged Aerosol Detector

For many years, lipid nanoparticles (LNPs) have been used as delivery vehicles for various payloads (especially various oligonucleotides and mRNA), finding numerous applications in drug and vaccine development. LNP stability and bilayer fluidity are determined by the identities and the amounts of the various lipids employed in the formulation and LNP efficacy is determined in large part by the lipid composition which usually contains a cationic lipid, a PEG‐lipid conjugate, cholesterol, and a zwitterionic helper phospholipid. Analytical methods developed for LNP characterization must be able to determine not only the identity and content of each individual lipid component (i.e., the parent lipids), but also the associated impurities and degradants. In this work, we describe an efficient and sensitive reversed‐phase chromatographic method with charged aerosol detection (CAD) suitable for this purpose. Sample preparation diluent and mobile phase pH conditions are critical and have been optimized for the lipids of interest. This method was validated for its linearity, accuracy, precision, and specificity for lipid analysis to support process and formulation development for new drugs and vaccines.

Thermoresponsive multicolor-emissive materials based on solid lipid nanoparticles

Despite the recent advances in the field of thermofluorochromism, the fabrication of thermoresponsive multicolor-emissive materials in a simple, low-cost and versatile manner still remains a challenge. Herein we accomplish this goal by expanding the concept of matrix-induced thermofluorochromism, where a sudden two-state variation of dyes' emission is promoted by the solid-liquid transition of a surrounding phase change material (e.g., paraffins). We demonstrate that this behavior can be transferred to the nanoscale by the synthesis of dye-loaded solid lipid nanoparticles, different types of which can then be combined into a single platform to obtain multicolor thermofluorochromism using a single type of emitter. Because of the reduced dimensions of these particles, they can be utilized to prepare transparent nanocomposites and inkjet-printed patterns showing complex thermoresponsive luminescence signals and applications ranging from smart displays to thermal sensing and high-security anti-counterfeiting.

Embracing nanomaterials' interactions with the innate immune system

Immunotherapy has firmly established itself as a compelling avenue for treating disease. Although many clinically approved immunotherapeutics engage the adaptive immune system, therapeutically targeting the innate immune system remains much less explored. Nanomedicine offers a compelling opportunity for innate immune system engagement, as many nanomaterials inherently interact with myeloid cells (e.g., monocytes, macrophages, neutrophils, and dendritic cells) or can be functionalized to target their cell-surface receptors. Here, we provide a perspective on exploiting nanomaterials for innate immune system regulation. We focus on specific nanomaterial design parameters, including size, form, rigidity, charge, and surface decoration. Furthermore, we examine the potential of high-throughput screening and machine learning, while also providing recommendations for advancing the field. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Concentration-Independent Multivalent Targeting of Cancer Cells by Genetically Encoded Core-Crosslinked Elastin/Resilin-like Polypeptide Micelles

Valency is a fundamental principle to control macromolecular interactions and is used to target specific cell types by multivalent ligand-receptor interactions using self-assembled nanoparticle carriers. At the concentrations encountered in solid tumors upon systemic administration, these nanoparticles are, however, likely to show critical micelle concentration (CMC)-dependent disassembly and thus loss of function. To overcome this limitation, core-crosslinkable micelles of genetically encoded resilin-/elastin-like diblock polypeptides were recombinantly synthesized. The amphiphilic constructs were covalently photo-crosslinked through the genetically encoded unnatural amino acid para-azidophenylalanine in their hydrophobic block and they carried different anticancer ligands on their hydrophilic block: the wild-type tenth human fibronectin type III domain, a GRGDSPAS peptide-both targeting α_vβ₃ integrin-and an engineered variant of the third fibronectin type III domain of tenascin C that is a death receptor 5 agonist. Although uncrosslinked micelles lost most of their targeting ability below their CMC, the crosslinked analogues remained active at concentrations up to 1000-fold lower than the CMC, with binding affinities that are comparable to antibodies.

Nanomedicine based approaches for combating viral infections

Millions of people die each year from viral infections across the globe. There is an urgent need to overcome the existing gap and pitfalls of the current antiviral therapy which include increased dose and dosing frequency, bioavailability challenges, non-specificity, incidences of resistance and so on. These stumbling blocks could be effectively managed by the advent of nanomedicine. Current review emphasizes over an enhanced understanding of how different lipid, polymer and elemental based nanoformulations could be potentially and precisely used to bridle the said drawbacks in antiviral therapy. The dawn of nanotechnology meeting vaccine delivery, role of RNAi therapeutics in antiviral treatment regimen, various regulatory concerns towards clinical translation of nanomedicine along with current trends and implications including unexplored research avenues for advancing the current drug delivery have been discussed in detail.

Chitosan modified squalene nanostructured lipid carriers as a promising adjuvant for freeze-dried ovalbumin vaccine

As immune adjuvants assisting vaccines, nanoparticle delivery systems have been widely exploited. Squalene, the major ingredient of approved adjuvant MF59, has great potential in activating immune responses. In the current study, model antigen ovalbumin (OVA) was encapsulated into squalene-based nanostructured lipid carriers (NLCs), and the chitosan, a cationic polysaccharide, was used for modifying nanoparticles to develop a functionalized and cationic nanoparticle delivery system (OVA-csNLCs). Firstly, the optimal formulation of csNLCs was successfully screened out, and had hydrodynamic diameter of 235.80 ± 5.99 nm and zeta potential of 34.90 ± 6.95 mV. Then, the generated OVA-csNLCs had no significant difference in hydrodynamic diameter and exhibited lower zeta potential of 19.03 ± 0.31 mV and high encapsulation efficiency of 83.4%. Sucrose (10%, w/w) was selected as optimal lyoprotectant, exhibiting good stability of OVA-csNLCs in the form of freeze-dried powder. More importantly, the OVA-csNLCs effectively promoted OVA antigen uptake by macrophage, significantly enhanced the level of OVA-specific IgG, and induced a Th2-based immune response in vivo. Furthermore, mice immunization experiment demonstrated that OVA-csNLCs had well biocompatibility and facilitated spleen lymphocytes proliferation. Above findings indicate that chitosan modified squalene nanostructured lipid carriers show promise as antigen delivery system and an open adjuvant platform.

Lipid-Based Nanocarrier System for the Effective Delivery of Nutraceuticals

Nutraceuticals possess several health benefits and functions; however, most nutraceuticals are prone to degradation in the gastrointestinal environment and have poor bioavailability. Application of a novel carrier system is of increasing importance to overcome obstacles and provide efficient applicability. Lipid-based nanocarriers provide a large surface-to-mass ratio, enhanced intestinal absorption by solubilization in the intestinal milieu, intestinal lymphatic transport, and altering enterocyte-based transport. A critical overview of the current limitation, preparation, and application of lipid-based nanocarriers (liposomes and niosomes) and lipid nanoparticles (SLNs and NLCs) is discussed. Physical and gastrointestinal stability and bioavailability of nanoencapsulated nutraceuticals are considered as well.

Liposomes: Structure, Biomedical Applications, and Stability Parameters With Emphasis on Cholesterol

Liposomes are essentially a subtype of nanoparticles comprising a hydrophobic tail and a hydrophilic head constituting a phospholipid membrane. The spherical or multilayered spherical structures of liposomes are highly rich in lipid contents with numerous criteria for their classification, including structural features, structural parameters, and size, synthesis methods, preparation, and drug loading. Despite various liposomal applications, such as drug, vaccine/gene delivery, biosensors fabrication, diagnosis, and food products applications, their use encounters many limitations due to physico-chemical instability as their stability is vigorously affected by the constituting ingredients wherein cholesterol performs a vital role in the stability of the liposomal membrane. It has well established that cholesterol exerts its impact by controlling fluidity, permeability, membrane strength, elasticity and stiffness, transition temperature (Tm), drug retention, phospholipid packing, and plasma stability. Although the undetermined optimum amount of cholesterol for preparing a stable and controlled release vehicle has been the downside, but researchers are still focused on cholesterol as a promising material for the stability of liposomes necessitating explanation for the stability promotion of liposomes. Herein, the prior art pertaining to the liposomal appliances, especially for drug delivery in cancer therapy, and their stability emphasizing the roles of cholesterol.

Nanostructured lipid carriers (NLCs) as drug delivery platform: Advances in formulation and delivery strategies

NLCs have provoked the incessant impulsion for the development of safe and valuable drug delivery systems owing to their exceptional physicochemical and then biocompatible characteristics. Throughout the earlier period, a lot of studies recounting NLCs based formulations have been noticeably increased. They are binary system which contains both solid and liquid lipids aiming to produce less ordered lipidic core. Their constituents particularly influence the physicochemical properties and effectiveness of the final product. NLCs can be fabricated by different techniques which are classified according to consumed energy. More utilization NLCs is essential due to overcome barriers surrounded by the technological procedure of lipid-based nanocarriers' formulation and increased information of the core mechanisms of their transport via various routes of administration. They can be used in different applications and by different routes such as oral, cutaneous, ocular and pulmonary. This review article seeks to present an overview on the existing situation of the art of NLCs for future clinics through exposition of their applications which shall foster their lucid use. The reported records evidently demonstrate the promise of NLCs for innovate therapeutic applications in the future.

Lipid-based nanoparticles for psoriasis treatment: a review on conventional treatments, recent works, and future prospects

Psoriasis is a lingering inflammatory skin disease that attacks the immune system. The abnormal interactions between T cells, immune cells, and inflammatory cytokines causing the epidermal thickening. International guidelines have recommended topical treatments for mild to moderate psoriasis whilst systemic and phototherapy treatments for moderate to severe psoriasis. However, current therapeutic approaches have a wider extent to treat moderate to severe type of psoriasis especially since the emergence of diverse biologic agents. In the meantime, topical delivery of conventional treatments has prompted many unsatisfactory effects to penetrate through the skin (stratum corneum). By understanding the physiology of stratum corneum barrier functions, scientists have developed different types of lipid-based nanoparticles like solid lipid nanoparticles, nanostructured lipid carriers, nanovesicles, and nanoemulsions. These novel drug delivery systems help the poorly solubilised active pharmaceutical ingredient reaches the targeted site seamlessly because of the bioavailability feature of the nanosized molecules. Lipid-based nanoparticles for psoriasis treatments create a paradigm for topical drug delivery due to their lipids' amphiphilic feature to efficiently encapsulate both lipophilic and hydrophilic drugs. This review highlights different types of lipid-based nanoparticles and their recent works of nano formulated psoriasis treatments. The encapsulation of psoriasis drugs through lipid nanocarriers unfold numerous research opportunities in pharmaceutical applications but also draw challenges for the future development of nano drugs.

Nanostructured Lipid Carriers (NLCs) for Oral Peptide Drug Delivery: About the Impact of Surface Decoration

This study was aimed to evaluate the impact of surfactants used for nanostructured lipid carriers (NLCs) to provide enzymatic protection for incorporated peptides. Insulin as a model peptide was ion paired with sodium dodecyl sulfate to improve its lipophilicity. Three NLC formulations containing polyethylene glycol ester (PEG-ester), polyethylene glycol ether (PEG-ether), and polyglycerol ester (PG-ester) surfactants were prepared by solvent diffusion method. NLCs were characterized regarding particle size, polydispersity index, and zeta potential. Biocompatibility of NLCs was assessed on Caco-2 cells via resazurin assay. In vitro lipolysis study was performed using a standard lipid digestion method. Proteolytic studies were performed in simulated gastric fluid containing pepsin and simulated intestinal fluid containing pancreatin. Lipophilicity of insulin in terms of log Poctanol/water was improved from -1.8 to 2.1. NLCs were in the size range of 64-217 nm with a polydispersity index of 0.2-0.5 and exhibited a negative surface charge. PG-ester NLCs were non-cytotoxic up to a concentration of 0.5%, PEG-ester NLCs up to a concentration of 0.25% and PEG-ether NLC up to a concentration of 0.125% (w/v). The lipolysis study showed the release of >90%, 70%, and 10% of free fatty acids from PEG-ester, PG-ester, and PEG-ether NLCs, respectively. Proteolysis results revealed the highest protective effect of PEG-ether NLCs followed by PG-ester and PEG-ester NLCs for incorporated insulin complex. Findings suggest that NLCs bearing substructures less susceptible to degrading enzymes on their surface can provide higher protection for incorporated peptides toward gastrointestinal proteases.

Solid Lipid Nanoparticles (SLNs): An Advanced Drug Delivery System Targeting Brain through BBB

The blood-brain barrier (BBB) plays a vital role in the protection and maintenance of homeostasis in the brain. In this way, it is an interesting target as an interface for various types of drug delivery, specifically in the context of the treatment of several neuropathological conditions where the therapeutic agents cannot cross the BBB. Drug toxicity and on-target specificity are among some of the limitations associated with current neurotherapeutics. In recent years, advances in nanodrug delivery have enabled the carrier system containing the active therapeutic drug to target the signaling pathways and pathophysiology that are closely linked to central nervous system (CNS) disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), multiple sclerosis (MS), brain tumor, epilepsy, ischemic stroke, and neurodegeneration. At present, among the nano formulations, solid lipid nanoparticles (SLNs) have emerged as a putative drug carrier system that can deliver the active therapeutics (drug-loaded SLNs) across the BBB at the target site of the brain, offering a novel approach with controlled drug delivery, longer circulation time, target specificity, and higher efficacy, and more importantly, reducing toxicity in a biomimetic way. This paper highlights the synthesis and application of SLNs as a novel nontoxic formulation strategy to carry CNS drugs across the BBB to improve the use of therapeutics agents in treating major neurological disorders in future clinics.

In Vitro Studies on Nasal Formulations of Nanostructured Lipid Carriers (NLC) and Solid Lipid Nanoparticles (SLN)

The nasal route has been used for many years for the local treatment of nasal diseases. More recently, this route has been gaining momentum, due to the possibility of targeting the central nervous system (CNS) from the nasal cavity, avoiding the blood-brain barrier (BBB). In this area, the use of lipid nanoparticles, such as nanostructured lipid carriers (NLC) and solid lipid nanoparticles (SLN), in nasal formulations has shown promising outcomes on a wide array of indications such as brain diseases, including epilepsy, multiple sclerosis, Alzheimer's disease, Parkinson's disease and gliomas. Herein, the state of the art of the most recent literature available on in vitro studies with nasal formulations of lipid nanoparticles is discussed. Specific in vitro cell culture models are needed to assess the cytotoxicity of nasal formulations and to explore the underlying mechanism(s) of drug transport and absorption across the nasal mucosa. In addition, different studies with 3D nasal casts are reported, showing their ability to predict the drug deposition in the nasal cavity and evaluating the factors that interfere in this process, such as nasal cavity area, type of administration device and angle of application, inspiratory flow, presence of mucoadhesive agents, among others. Notwithstanding, they do not preclude the use of confirmatory in vivo studies, a significant impact on the 3R (replacement, reduction and refinement) principle within the scope of animal experiments is expected. The use of 3D nasal casts to test nasal formulations of lipid nanoparticles is still totally unexplored, to the authors best knowledge, thus constituting a wide open field of research.

Formulation, process, and storage strategies for lyophilizates of lipophilic nanoparticulate systems established based on the two models paliperidone palmitate and solid lipid nanoparticles

Lyophilization formulation and process development for lipophilic nanoparticle (NPs) products is highly challenging as the NPs have a low colloidal stability. We compared two different NP types, pure paliperidone palmitate nanocrystals and trimyristin solid lipid nanoparticles regarding formulation, process, and storage stability aspects. Freeze-thaw studies were conducted to investigate the basic formulation aspects such as buffer type, pH, and ionic strength as well as different cryoprotectants. In freeze-drying conventional ramp freezing was performed and compared to freezing with an annealing step added or with controlled ice nucleation. Different formulations were lyophilized and tested for short-term storage stability up to 6 weeks. Samples were analyzed for particle size, subvisible particle number, specific surface area, residual moisture, crystallinity, and glass transition temperature. Sucrose significantly better stabilized both NP types against freeze-thaw stress compared to mannitol demonstrating the importance of a fully amorphous matrix. While the impact of buffer type and pH was negligible, the aggregation propensity of NPs was reduced in presence of NaCl. The freezing step also impacted NP aggregation but the effect was less important than the formulation design. Surfactants did not necessarily improve the colloidal stability but resulted in a lower glass transition temperature of the lyophilizates and may cause phase separation which limits storage stability. This hurdle can be overcome by using a hydroxypropyl-β-cyclodextrin/ sucrose mixture as cryoprotectant. In general, we could show a similar freeze-drying behavior of the two NP types. Thus, we established a formulation and process approach to achieve stable lyophilizates of lipophilic NPs based on two different types of NPs. The general rules should be transferable to other NPs facilitating lyophilization development.

Teucrium polium extract-loaded solid lipid nanoparticles: A design and in vitro anticancer study

Teucrium polium extract (TPE) is a natural product with potent anticancer activity because of its terpenoid and flavonoid content. The aim of this study was to synthesize solid lipid nanoparticles (SLN) containing T. polium extract (TPE-SLNs) and to evaluate its anti-cancer effect. Formulations of TPE-SLNs were prepared using high-shear homogenization followed by the ultra-sonication technique. Then the TPE-SLNs were characterized by dynamic light scattering (DLS), Zetasizer and field-emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy methods. After confirming the presence of nanoparticles, its anti-proliferative activity was evaluated on Ntra-2 cancer cells and compared to human foreskin fibroblasts (HFF) as a normal cell line by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The pro-apoptotic (flow cytometry) and quantitative PCR (qPCR) and anti-angiogenic (chick chorioallantoic membrane (CAM)) and anti-inflammatory (qPCR) effects of TPE-SLNs were assessed by various methods. TPE-SLNs (85.5 nm, PDI: 0.39, and zeta potential: -25.5 mv) were inhibited by the proliferation of Ntra-2 cancer cells with half-maximal inhibitory concentration (IC₅₀ ; 106.58 µg/ml). Moreover, by increasing the expression of caspase-3,9 and decreasing the expression of interleukin 6 (IL-6), IL-1b, and Bcl-2 genes, apoptosis and anti-inflammatory effects were observed. Reduction of angiogenesis was observed by the reduction of genes involved in angiogenesis and reduction of vascular and embryonic factors in the CAM assay. Activation of various mechanisms of inhibiting cancer cells in the treatment of nanoparticles was demonstrated in the present study. Therefore, these nanoparticles can be recommended for therapeutic purposes. PRACTICAL APPLICATIONS: Solid lipid nanoparticles (SLNs) are composed of pure solid fats and have been researched for many applications. Advantages such as high safety, low toxicity, control of drug release, and increase in chemical stability of loaded drugs distinguish these systems from other colloidal systems. According to the results of this study, solid lipid nanoparticles (SLN) containing T. polium extract showed their anti-cancer effects through various strategies such as inhibiting angiogenesis, inhibiting inflammation, and inducing apoptosis on Ntra-2 cells. These results make it possible to apply these nanocarriers in the loading and transport of drugs to treat various diseases such as cancer.

Topotecan-loaded thermosensitive nanocargo for tumor therapy: In vitro and in vivo analyses

This study demonstrates the development of topotecan (TCN) loaded thermosensitive nanocargos (TCN-TS-NC) for intramuscular (IM) administration with enhanced antitumor activity. In this regards, TCN loaded temperature dependent solid lipid nanoparticles (SLNs) were prepared with micro-emulsion method, which were then incorporated into temperature sensitive poloxamer solution to develop TCN-TS-NC. The particle size, entrapment efficiency (%EE), zeta potential and transmission electron microscopy (TEM) analysis of the TCN-TS-NC were performed. Moreover, the inject-ability, release pattern, apoptosis, cellular uptake, pharmacokinetics and antitumor studies of the TCN-TS-NC were attained and compared with TCN solution and TCN-Emulgel (poloxamer solution containing TCN). At room temperature, the TCN loaded SLNs were solid and poloxamer solution remains liquid, however, TCN loaded SLNs melted to liquid and Emulgel converted into gel from, at body temperature, resulting controlled release of the incorporated drug. The TCN-TS-NC showed enhanced cellular uptake and better apoptosis. Similarly, it reduces C_max and sustained its level for a significantly longer time in rats, as compared to the TCN-Emulgel and TCN solution. Moreover, a significantly improved antitumor activity was observed in TCN-TS-NC treated tumor bearing athymic nude mice when compared with the control, TCN solution and TCN-Emulgel applied mice. Thus, the TCN-TS-NC system showed control release of the drug with no initial fast effect. Furthermore, it enhanced the antitumor activity of TCN with comparatively no toxicity. It is therefore concluded that TCN-TS-NC could be a potentially more suitable drug delivery system for the delivery of TCN.

Light-Activated Biomedical Applications of Chlorophyll Derivatives

Tetrapyrroles are the basis of essential physiological functions in most living organisms. These compounds represent the basic scaffold of porphyrins, chlorophylls, and bacteriochlorophylls, among others. Chlorophyll derivatives, obtained by the natural or artificial degradation of chlorophylls, present unique properties, holding great potential in the scientific and medical fields. Indeed, they can act as cancer-preventing agents, antimutagens, apoptosis inducers, efficient antioxidants, as well as antimicrobial and immunomodulatory molecules. Moreover, thanks to their peculiar optical properties, they can be exploited as photosensitizers for photodynamic therapy and as vision enhancers. Most of these molecules, however, are highly hydrophobic and poorly soluble in biological fluids, and may display undesired toxicity due to accumulation in healthy tissues. The advent of nanomedicine has prompted the development of nanoparticles acting as carriers for chlorophyll derivatives, facilitating their targeted administration with demonstrated applicability in diagnosis and therapy. In this review, the chemical and physical properties of chlorophyll derivatives that justify their usage in the biomedical field, with particular regard to light-activated dynamics are described. Their role as antioxidants and photoactive agents are discussed, introducing the most recent nanomedical applications and focusing on inorganic and organic nanocarriers exploited in vitro and in vivo.

The in vitro effect of nanoliposomal amphotericin B against two clinically important dermatophytes

AIMS

The present study aimed to investigate the antifungal activity of amphotericin B-loaded nanoliposomes against Trichophyton interdigitale and Trichophyton rubrum. Moreover, it was attempted to assess the obtained resistance in vitro.

METHODS

In total, 29 archived clinical strains, namely, T. interdigitale (n = 16) and T. rubrum (n = 13), were included in this study. These strains were determined using a previous ITS1-ITS2 region sequence. Moreover, a liposomal formulation of amphotericin B was formulated by a thin-film hydration method. Particle size, polydispersity index (PdI), and zeta potential (ZP) were measured by a Zetasizer. Furthermore, physicochemical properties, such as appearance, aggregation of particles, particle size, PdI, and ZP, were determined at 0-, 1-, and 3-month intervals. A scanning electron microscope (SEM) was also used to examine nanoparticles structure. The minimum inhibitory concentration (MIC) of amphotericin B-loaded nanoliposomes, itraconazole, efinaconazole, terbinafine, and ciclopirox was determined according to the protocol of the broth microdilution method of CLSI M38-A2. The morphological changes of T. interdigitale and T. rubrum strains exposed to the amphotericin B-loaded nanoliposomes were observed using SEM.

RESULTS

The amphotericin B-loaded nanoliposomes displayed a lower MIC compared to those of the amphotericin B and liposomes when used separately. Based on the results, amphotericin B-loaded nanoliposomes induced no drug resistance in any of the tested strains.

CONCLUSION

Accordingly, amphotericin B-loaded nanoliposomes can be a potent antifungal for the topical treatment of onychomycosis. There was no in vitro evidence regarding the resistance of the tested strains to amphotericin B-loaded nanoliposomes. This reflects that amphotericin B-loaded nanoliposomes have a low probability to induce drug resistance in dermatophyte species.

An Overview on Topical Administration of Carotenoids and Coenzyme Q10 Loaded in Lipid Nanoparticles

Carotenoids and coenzyme Q10 are naturally occurring antioxidant compounds that are also found in human skin. These bioactive compounds have been the focus of considerable research due to their antioxidant, anti-inflammatory, and photoprotective properties. In this review, the current state of the art in the encapsulation of carotenoids and coenzyme Q10 in lipid nanoparticles to improve their bioavailability, chemical stability, and skin absorption is discussed. Additionally, the main findings are highlighted on the cytotoxic and photoprotective effects of these systems in the skin.

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.

Improving the bioavailability and bioactivity of garlic bioactive compounds via nanotechnology

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future.

Freeze-drying of nanoparticles: How to overcome colloidal instability by formulation and process optimization

Lyophilization of nanoparticle (NP) suspensions is a promising technology to improve stability, especially during long-term storage, and offers new routes of administration in solid state. Although considered as a gentle drying process, freeze-drying is also known to cause several stresses leading to physical instability, e.g. aggregation, fusion, or content leakage. NPs are heterogeneous regarding their physico-chemical properties which renders them different in their sensitivity to lyophilization stress and upon storage. But still basic concepts can be deducted. We summarize basic colloidal stabilization mechanisms of NPs in the liquid and the dried state. Furthermore, we give information about stresses occurring during the freezing and the drying step of lyophilization. Subsequently, we review the most commonly investigated NP types including lipophilic, polymeric, or vesicular NPs regarding their particle properties, stabilization mechanisms in the liquid state, and important freeze-drying process, formulation and storage strategies. Finally, practical advice is provided to facilitate purposeful formulation and process development to achieve NP lyophilizates with high colloidal stability.

CRISPR/Cas9 in cancer: An attempt to the present trends and future prospects

Cancer is the second leading cause of death globally. Series of sequential, repeated genetic changes and epigenetic modifications are leading to the formation of tumors. These tumors subsequently causing the infected cells to invade and transform their surrounding cells by metastasis are some hallmarks in cancer. Although tremendous efforts have been extended for structurally characterizing the numerous genomic mutations undergoing in cancer cells, there is a lack of information regarding the functions of many mutated genes. Clustered Regularly Interspaced Short Palindromic repeats/CRISPR-associated nuclease 9 (CRISPR/Cas9) has become a robust method for building changes in genome of many organisms. Recent reports have suggested that modification of CRISPR/Cas9 can provide plot form to probe the mechanisms in tumorigenesis and in cancer therapies. This review focuses on the historical perspectives of CRISPR/Cas9. The study highlights the applications and also role in cancer cell genome editing, which is helpful to understand the dynamics. Intense research in progress on mechanism of action of CRISPR/Cas9 has been reviewed and critically discussed. Further, relevant literature on animal models focusing on various approaches has been highlighted to emphasize the therapeutics of CRISPR/Cas9 with current trends and future challenges.

Design, Preparation, and Characterization of Effective Dermal and Transdermal Lipid Nanoparticles: A Review

Limited permeability through the stratum corneum (SC) is a major obstacle for numerous skin care products. One promising approach is to use lipid nanoparticles as they not only facilitate penetration across skin but also avoid the drawbacks of conventional skin formulations. This review focuses on solid lipid nanoparticles (SLNs), nanostructured lipid nanocarriers (NLCs), and nanoemulsions (NEs) developed for topical and transdermal delivery of active compounds. A special emphasis in this review is placed on composition, preparation, modifications, structure and characterization, mechanism of penetration, and recent application of these nanoparticles. The presented data demonstrate the potential of these nanoparticles for dermal and transdermal delivery.

A systematic assessment of the relationship between synthetic surfactants and mucosal adjuvanticity

Intranasal immunization with surfactants as vaccine adjuvants enhances protective immunity against invasive mucosal pathogens. However, the effects of surfactants and their adjuvanticity on mucosal immune responses remain unclear. Comparison of the mucosal adjuvanticity of 20 water-soluble surfactants from the four classes based upon the polarity composition of the hydrophilic headgroup revealed that the order of mucosal adjuvanticity was as follows: amphoteric > nonionic > cationic > anionic. Within the same class, each surfactant displayed different adjuvanticity values. Analysis of the diameter and ζ-potential of amphoteric surfactant-OVA complexes and their surface physicochemical properties revealed that the diameter was approximately 100 nm, which is considered suitable for immune induction, and that the ζ-potential of the anionic surfactant-OVA complexes was exceedingly negative. The increase in the number of carbon atoms in the hydrophobic tailgroups of the amphoteric surfactant resulted in an increase in the OVA-specific Ab titers. Our findings demonstrate that amphoteric surfactants exhibit potent mucosal adjuvanticity and highlight the importance of the number of carbon atoms in the tailgroups and the diameter and ζ-potential of the complexes when designing mucosal adjuvants.

Optimization and antimicrobial efficacy of curcumin loaded solid lipid nanoparticles against foodborne bacteria in hamburger patty

The aim of the present study was to design a delivery system of curcumin (CU) loaded solid lipid nanoparticles (CU-CSLNs) for evaluating the antimicrobial properties in hamburger patty. Solid lipid nanoparticle (SLN) was prepared through a homogenizing technique. A response surface methodology was applied to optimize the CU-CSLNs to minimize the particle size (PS), polydispersity index (PDI), as well as to maximize the zeta potential to avoid aggregation of particles. The optimized sample revealed a spherical morphology under scanning electron microscope (SEM) and dynamic light scattering (DLS) with particle sizes of 126.87 ± 0.94 nm and 0.21 ± 0.025 PDI. The zeta potential and encapsulation efficiency (EE %) were found to be -30 ± 0.3 mV and 99.96 ± 0.01%, respectively. The CSLNs exhibited higher in vitro antimicrobial effect (142 µg·ml^-1 ) against Staphylococcus aureus and generic Escherichia coli as compared to free CU (1000 µg·ml^-1 ). Finally, the CSLNs antimicrobial effect was tested in hamburger patty inoculated with foodborne pathogens during eight days of storage at 4 °C. The results indicated that CSLNs had a higher antimicrobial effect than free CU. This study provides insight into the preparation of the novel antimicrobial nanoparticles for food safety applications.

Development of Perphenazine-Loaded Solid Lipid Nanoparticles: Statistical Optimization and Cytotoxicity Studies

OBJECTIVE

Perphenazine (PPZ), as a typical antipsychotic medical substance, has the same effectiveness compared to atypical antipsychotic medications for the treatment of schizophrenia. Despite the lipophilic essence, PPZ encounters limited bioavailability caused by the first-pass metabolism following oral administration. In the present study, PPZ-containing solid lipid nanoparticles (PPZ-SLNs) were prepared and optimized based on different factors, including lipid and surfactant amount, to develop appropriate and safe novel oral dosage forms of PPZ.

METHODS

The solvent emulsification-evaporation method was utilized to form SLNs by using soybean lecithin, glycerol monostearate (GMS), and Tween 80. Statistical optimization was done by the Box-Behnken design method to achieve formulation with optimized particle size, entrapment efficiency, and zeta potential. Also, transmission electron microscopy, in vitro release behavior, differential scanning calorimetry (DSC), and powder X-ray diffractometry (P-XRD) studies and cytotoxicity studies were assessed.

RESULTS

Optimization exhibited the significant effect of various excipients on SLN characteristics. Our finding indicated that the mean particle size, zeta potential, and entrapment efficiency of optimized PPZ-SLN were, respectively, 104 ± 3.92 nm, -28 ± 2.28 mV, and 83% ± 1.29. Drug release of PPZ-SLN was observed to be greater than 90% for 48 h that emphasized a sustained-release pattern. The DSC and P-XRD studies revealed the amorphous state of PPZ-SLN. FTIR spectra showed no incompatibility between the drug and the lipid. Performing cytotoxicity studies indicated no significant cytotoxicity on HT-29 cell culture.

CONCLUSION

Our study suggests that PPZ-SLNs can make a promising vehicle for a suitable therapy of schizophrenia for the oral drug delivery system.

A study to enhance the oral bioavailability of s-adenosyl-l-methionine (SAMe): SLN and SLN nanocomposite particles

The endogenous molecule, S-adenosyl-l-methionine (SAMe) is a key factor due to its role in the methylation cycle and modulation of monoaminergic neurotransmission. Since many mental disorders have linked to the monoaminergic system, the level of SAMe in blood and cerebrospinal fluid is important in the treatment of major depression. In this study, solid lipid nanoparticles (SLN) were prepared in order to increase the limited oral bioavailability of SAMe, and SLN based nanocomposite particles (SAMe-SLN-NC) were further developed using an enteric polymer for passive targeting of intestinal lymphatic system. In this manner, it was also aimed to protect SAMe loaded SLN from harsh gastric environment as well as hepatic first-pass metabolism. Dynamic light scattering (DLS) analysis of SLN was performed, drug content was measured, SAMe release patterns were examined and the permeation ability of SAMe was investigated by the Parallel Artificial Membrane Permeability Assay (PAMPA) to characterize SAMe loaded SLN formulation. According to the PAMPA results, SAMe-SLN with the average particle size of 242 nm showed enhanced SAMe permeability in comparison to pure drug. Delayed drug release obtained by SLN nanocomposite particles indicated the protection of drug-loaded SLN in the acidic gastric medium and their intact presence in the intestine. SAMe solution or particle suspensions were prepared using 0.45 (w/v) hydroxypropyl methylcellulose aqueous solution to be applied to groups of animals for pharmacokinetic studies. In vivo pharmacokinetic parameters revealed enhancement in relative bioavailability of SAMe upon oral administration of SLN based formulations. This was attributed to intact absorption of lipid matrix through lymphatic path. A statistically significant increase in SAMe plasma levels was obtained at 15th and 30th minutes with SAMe-SLN and at 2nd and 4th hours with SAMe-SLN-NC. Overall results suggest that SLN is a promising carrier to passive lymphatic targeting of SAMe and novel SLN nanocomposite particles which presented efficient oral bioavailability is a potential way for oral delivery of SAMe and treatment of major depression.

Lipid Nanoparticles as Carriers for Bioactive Delivery

Nanotechnology has made a great impact on the pharmaceutical, biotechnology, food, and cosmetics industries. More than 40% of the approved drugs are lipophilic and have poor solubility. This is the major rate-limiting step that influences the release profile and bioavailability of drugs. Several approaches have been reported to administer lipophilic drugs with improved solubility and bioavailability. Nanotechnology plays a crucial role in the targeted delivery of poorly soluble drugs. Nanotechnology-based drug delivery systems can be classified as solid lipid nanoparticulate drug delivery systems, emulsion-based nanodrug delivery systems, vesicular drug delivery systems, etc. Nanotechnology presents a new frontier in research and development to conquer the limitations coupled with the conventional drug delivery systems through the formation of specific functionalized particles. This review presents a bird's eye view on various aspects of lipid nanoparticles as carriers of bioactive molecules that is, synthesis, characterization, advantage, disadvantage, toxicity, and application in the medical field. Update on recent development in terms of patents and clinical trials of solid lipid nanoparticles (SLNs) and nanostructure lipid carriers (NLCs) have also been discussed in this article.

Nanotechnology based solutions for anti-leishmanial impediments: a detailed insight

As a neglected tropical disease, Leishmaniasis is significantly instigating morbidity and mortality across the globe. Its clinical spectrum varies from ulcerative cutaneous lesions to systemic immersion causing hyperthermic hepato-splenomegaly. Curbing leishmanial parasite is toughly attributable to the myriad obstacles in existing chemotherapy and immunization. Since the 1990s, extensive research has been conducted for ameliorating disease prognosis, by resolving certain obstacles of conventional therapeutics viz. poor efficacy, systemic toxicity, inadequate drug accumulation inside the macrophage, scarce antigenic presentation to body's immune cells, protracted length and cost of the treatment. Mentioned hurdles can be restricted by designing nano-drug delivery system (nano-DDS) of extant anti-leishmanials, phyto-nano-DDS, surface modified-mannosylated and thiolated nano-DDS. Likewise, antigen delivery with co-transportation of suitable adjuvants would be achievable through nano-vaccines. In the past decade, researchers have engineered nano-DDS to improve the safety profile of existing drugs by restricting their release parameters. Polymerically-derived nano-DDS were found as a suitable option for oral delivery as well as SLNs due to pharmacokinetic re-modeling of drugs. Mannosylated nano-DDS have upgraded macrophage internalizing of nanosystem and the entrapped drug, provided with minimal toxicity. Cutaneous Leishmaniasis (CL) was tackling by the utilization of nano-DDS designed for topical delivery including niosomes, liposomes, and transfersomes. Transfersomes, however, appears to be superior for this purpose. The nanotechnology-based solution to prevent parasitic resistance is the use of Thiolated drug-loaded and multiple drugs loaded nano-DDS. These surfaces amended nano-DDS possess augmented IC50 values in comparison to conventional drugs and un-modified nano-DDS. Phyto-nano-DDS, another obscure horizon, have also been evaluated for their anti-leishmanial response, however, more intense assessment is a prerequisite. Impoverished Cytotoxic T-cells response followed by Leishmanial antigen proteins delivery have also been vanquished using nano-adjuvants. The eminence of nano-DDS for curtailment of anti-leishmanial chemotherapy and immunization associated challenges are extensively summed up in this review. This expedited approach is ameliorating the Leishmaniasis management successfully. Alongside, total to partial eradication of this disease can be sought along with associated co-morbidities.

Application of solid lipid nanoparticles as a long-term drug delivery platform for intramuscular and subcutaneous administration: In vitro and in vivo evaluation

The purpose of this work was to evaluate solid lipid nanoparticles (SLNs) as a long acting injectable drug delivery platform for intramuscular and subcutaneous administration. SLNs were developed with a low (unsaturated) and high (supersaturated) drug concentration at equivalent lipid doses. The impact of the drug loading as well as the administration route for the SLNs using two model compounds with different physicochemical properties were explored for their in vitro and in vivo performance. Results revealed that drug concentration had an influence on the particle size and entrapment efficiency of the SLNs and, therefore, indirectly an influence on the C_max/dose and AUC/dose after administration to rats. Furthermore, the in vitro drug release was compound specific, and linked to the affinity of the drug compounds towards the lipid matrix and release medium. The pharmacokinetic parameters resulted in an increased t_max, t_1/2 and mean residence time (MRT) for all formulations after intramuscular and subcutaneous dosing, when compared to intravenous administration. Whereas, the subcutaneous injections performed better for those parameters than the intramuscular injections, because of the higher blood perfusion in the muscles compared with the subcutaneous tissues. In conclusion, SLNs extend drug release, need to be optimized for each drug, and are appropriate carriers for the delivery of drugs that require a short-term sustained release in a timely manner.

Co-delivery of hesperidin and clarithromycin in a nanostructured lipid carrier for the eradication of Helicobacter pylori in vitro

Effective and precise eradication of Helicobacter pylori (H. pylori) is the most promising approach to avoid H. pylori-related gastrointestinal disorders. The present study was conducted to demonstrate the efficacy of the co-delivery of hesperidin (Hesp) and clarithromycin (CLR) in nanostructured lipid carriers (NLCs) against H. pylori. We have produced a new delivery system by combining bioflavonoid Hesp and CLR NLCs to address the failure in single antibiotic therapies. Briefly, a blend of solid lipid, liquid lipid, and surfactant was used. Homogeneous NLCs with all the formulations showed a nano size and surface-negative charge and presented high in vitro stability and slow release of the drug even after 24 h. Bioimaging studies by scanning electron microscopy, transmission electron microscopy, and imaging flow cytometry indicated that NLCs interacted with the membrane by adhering to the outer cell membrane and disrupted the membrane that resulted in the leakage of cytoplasmic contents. The prepared NLCs provide sustained and controlled drug release that can be used to increase the rate of H. pylori eradication.