Short Term Stability Testing of Efavirenz-Loaded Solid Lipid Nanoparticle (SLN) and Nanostructured Lipid Carrier (NLC) Dispersions

Fexofenadine-loaded chitosan coated solid lipid nanoparticles (SLNs): A potential oral therapy for ulcerative colitis

The targeting and mucoadhesive features of chitosan (CS)-linked solid lipid nanoparticles (SLNs) were exploited to efficiently deliver fexofenadine (FEX) into the colon, forming a novel and potential oral therapeutic option for ulcerative colitis (UC) treatment. Different FEX-CS-SLNs with varied molecular weights of CS were prepared and optimized. Optimized FEX-CS-SLNs exhibited 229 ± 6.08 nm nanometric size, 36.3 ± 3.18 mV zeta potential, 64.9 % EE, and a controlled release profile. FTIR, DSC, and TEM confirmed good drug entrapment and spherical particles. Mucoadhesive properties of FEX-CS-SLNs were investigated through mucin incubation and exhibited considerable mucoadhesion. The protective effect of FEX-pure, FEX-market, and FEX-CS-SLNs against acetic acid-induced ulcerative colitis in rats was examined. Oral administration of FEX-CS-SLNs for 14 days before ulcerative colitis induction reversed UC symptoms and almost restored the intestinal mucosa to normal integrity and inhibited Phosphatidylinositol-3 kinase (73.6 %), protein kinase B (73.28 %), and elevated nuclear factor erythroid 2-related factor 2 (185.9 %) in colonic tissue. Additionally, FEX-CS-SLNs inhibited tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) to (70.79 % & 72.99 %) in colonic tissue. The ameliorative potential of FEX-CS-SLNs outperformed that of FEX-pure and FEX-market. The exceptional protective effect of FEX-CS-SLNs makes it a potentially effective oral system for managing ulcerative colitis.

Toward a Platform for the Treatment of Burns: An Assessment of Nanoemulsions vs. Nanostructured Lipid Carriers Loaded with Curcumin

Curcumin is a highly promising substance for treating burns, owing to its anti-inflammatory, antioxidant, antimicrobial, and wound-healing properties. However, its therapeutic use is restricted due to its hydrophobic nature and low bioavailability. This study was conducted to address these limitations; it developed and tested two types of lipid nanocarriers, namely nanoemulsions (NE-CUR) and nanostructured lipid carriers (NLC-CUR) loaded with curcumin, and aimed to identify the most suitable nanocarrier for skin burn treatment. The study evaluated various parameters, including physicochemical characteristics, stability, encapsulation efficiency, release, skin permeation, retention, cell viability, and antimicrobial activity. The results showed that both nanocarriers showed adequate size (~200 nm), polydispersity index (~0.25), and zeta potential (~>-20 mV). They also showed good encapsulation efficiency (>90%) and remained stable for 120 days at different temperatures. In the release test, NE-CUR and NCL-CUR released 57.14% and 51.64% of curcumin, respectively, in 72 h. NE-CUR demonstrated better cutaneous permeation/retention in intact or scalded skin epidermis and dermis than NLC-CUR. The cell viability test showed no toxicity after treatment with NE-CUR and NLC-CUR up to 125 μg/mL. Regarding microbial activity assays, free curcumin has activity against P. aeruginosa, reducing bacterial growth by 75% in 3 h. NE-CUR inhibited bacterial growth by 65% after 24 h, and the association with gentamicin had favorable results, while NLC-CUR showed a lower inhibition. The results demonstrated that NE-CUR is probably the most promising nanocarrier for treating burns.

Brain-targeted delivery of Valsartan using solid lipid nanoparticles labeled with Rhodamine B; a promising technique for mitigating the negative effects of stroke

The brain is a vital organ that is protected from the general circulation and is distinguished by the presence of a relatively impermeable blood brain barrier (BBB). Blood brain barrier prevents the entry of foreign molecules. The current research aims to transport valsartan (Val) across BBB utilizing solid lipid nanoparticles (SLNs) approach to mitigate the adverse effects of stroke. Using a 3²-factorial design, we could investigate and optimize the effect of several variables in order to improve brain permeability of valsartan in a target-specific and sustained-release manner, which led to alleviation of ischemia-induced brain damage. The impact of each of the following independent variables was investigated: lipid concentration (% w/v), surfactant concentration (% w/v), and homogenization speed (RPM) on particle size, zeta potential (ZP), entrapment efficiency (EE) %, and cumulative drug release percentage (CDR) %. TEM images revealed a spherical form of the optimized nanoparticles, with particle size (215.76 ± 7.63 nm), PDI (0.311 ± 0.02), ZP (-15.26 ± 0.58 mV), EE (59.45 ± 0.88%), and CDR (87.59 ± 1.67%) for 72 hours. SLNs formulations showed sustained drug release, which could effectively reduce the dose frequency and improve patient compliance. DSC and X-ray emphasize that Val was encapsulated in the amorphous form. The in-vivo results revealed that the optimized formula successfully delivered Val to the brain through intranasal rout as compared to a pure Val solution and evidenced by the photon imaging and florescence intensity quantification. In a conclusion, the optimized SLN formula (F9) could be a promising therapy for delivering Val to brain, alleviating the negative consequences associated with stroke.

Chitosan tamarind-based nanoparticles as a promising approach for topical application of curcumin intended for burn healing: in vitro and in vivo study

One of the most prevalent worldwide problems that affect all ages and genders is skin burn. The goal of our study was to assess the ability of curcumin nanoparticles to cure a rat burn model. Three formulations were selected after several tests were performed including investigation of encapsulation efficiency, particle size and zeta potential measurements. In vitro release was achieved on the three selected formulations. The effectiveness of the chosen formulation for healing was evaluated. The induced burn wound was smeared, starting just after excision, once daily with curcumin nanoparticles for 18 days. Our findings revealed that curcumin nanoparticles improved the burn healing potential by augmenting the skin regeneration indices as evidenced by enhancing the new production of hyaluronic acid and collagen type I. Additionally, curcumin nanoparticles could increase levels of vascular endothelial growth factor and alpha smooth muscle activity while drastically reducing the skin's tumour necrosis factor content, revealing a significant potential for burn healing process that is also reflected in the histopathological and immunohistochemical studies. Finally, our results demonstrated that curcumin nanoparticles revealed a significant potential for burn healing than curcumin alone due to its potent antimicrobial, antioxidant and anti-inflammatory properties.

Preparation, characterization, and pharmacological application of oral Honokiol-loaded solid lipid nanoparticles for diabetic neuropathy

Honokiol is a phytochemical component with a variety of pharmacological properties. However, the major limitation of Honokiol is its poor solubility and low oral bioavailability. In this study, we formulated and characterized oral Honokiol-loaded solid lipid nanoparticles (SLNs) to enhance bioavailability and then evaluated their effectiveness in experimental diabetic neuropathy (DN). The finalized formulation has a spherical morphology, a particle size (PS) of 121.31 ± 9.051 nm, a polydispersity index (PDI) of 0.249 ± 0.002, a zeta potential (ZP) of -20.8 ± 2.72 mV, and an entrapment efficiency (% EE) of 88.66 ± 2.30 %. In-vitro release data shows, Honokiol-SLNs displayed a sustained release profile at pH (7.4). The oral bioavailability of Honokiol-SLNs was remarkably greater (8-fold) than Honokiol-Pure suspension. The neuroprotective property of Honokiol-SLNs was initially demonstrated against hydrogen peroxide H2O2-stimulated PC12 (pheochromocytoma) cells. Furthermore, results of in-vivo studies demonstrated that treatment with Honokiol-SLNs significantly (p < 0.001) suppressed oxidative stress by inhibition of nuclear factor kappa B (NF-κB) and significant (p < 0.001) upregulation of nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling in the spinal cord. The expression of transient receptor potential melastatin 8(TRPM8) and transient receptor potential vanilloid 1 (TRPV1) was significantly (p < 0.001) downregulated. Honokiol-SLNs inhibited apoptosis by significant (p < 0.001) downregulation of cleaved caspase-3 expression in the spinal cord. These findings demonstrate that Honokiol-SLNs providedbetter neuroprotection in DN because of higher oral bioavailability.

Amelioration of the therapeutic potential of gefitinib against breast cancer using nanostructured lipid carriers

Aim: This study aimed to improve the delivery and therapeutic potential of gefitinib (GTB) against breast cancer by preparing GTB-loaded, nanostructured lipid carriers (GTB-NLCs). Materials & methods: Box-Behnken design was used for optimization and GTB was loaded into NLCs using ultrasonication. The GTB-NLCs were characterized using in vitro, ex vivo and in vivo studies. The anticancer efficacy of GTB-NLCs was evaluated using 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide cytotoxicity and flow cytometry on MCF-7 breast cancer cell lines. Results: Optimized GTB-NLCs were successfully characterized and demonstrated improved internalization and enhanced cytotoxicity compared with plain GTB. Gut permeation studies showed enhanced intestinal permeability, and pharmacokinetic analysis revealed 2.6-fold improvement in GTB oral bioavailability. Conclusion: GTB-NLCs effectively enhanced the therapeutic potential of GTB against breast cancer.

Combined Donepezil with Astaxanthin via Nanostructured Lipid Carriers Effective Delivery to Brain for Alzheimer's Disease in Rat Model

Introduction

Donepezil (DPL), a specific acetylcholinesterase inhibitor, is used as a first-line treatment to improve cognitive deficits in Alzheimer's disease (AD) and it might have a disease modifying effect. Astaxanthin (AST) is a natural potent antioxidant with neuroprotective, anti-amyloidogenic, anti-apoptotic, and anti-inflammatory effects. This study aimed to prepare nanostructured lipid carriers (NLCs) co-loaded with donepezil and astaxanthin (DPL/AST-NLCs) and evaluate their in vivo efficacy in an AD-like rat model 30 days after daily intranasal administration.

Methods

DPL/AST-NLCs were prepared using a hot high-shear homogenization technique, in vitro examined for their physicochemical parameters and in vivo evaluated. AD induction in rats was performed by aluminum chloride. The cortex and hippocampus were isolated from the brain of rats for biochemical testing and histopathological examination.

Results

DPL/AST-NLCs showed z-average diameter 149.9 ± 3.21 nm, polydispersity index 0.224 ± 0.017, zeta potential -33.7 ± 4.71 mV, entrapment efficiency 81.25 ±1.98% (donepezil) and 93.85 ±1.75% (astaxanthin), in vitro sustained release of both donepezil and astaxanthin for 24 h, spherical morphology by transmission electron microscopy, and they were stable at 4-8 ± 2°C for six months. Differential scanning calorimetry revealed that donepezil and astaxanthin were molecularly dispersed in the NLC matrix in an amorphous state. The DPL/AST-NLC-treated rats showed significantly lower levels of nuclear factor-kappa B, malondialdehyde, β-site amyloid precursor protein cleaving enzyme-1, caspase-3, amyloid beta (Aβ1‑42), and acetylcholinesterase, and significantly higher levels of glutathione and acetylcholine in the cortex and hippocampus than the AD-like untreated rats and that treated with donepezil-NLCs. DPL/AST-NLCs showed significantly higher anti-amyloidogenic, antioxidant, anti-acetylcholinesterase, anti-inflammatory, and anti-apoptotic effects, resulting in significant improvement in the cortical and hippocampal histopathology.

Conclusion

Nose-to-brain delivery of DPL/AST-NLCs is a promising strategy for the management of AD.

Chitosan-Coated SLN: A Potential System for Ocular Delivery of Metronidazole

Ophthalmic drops for ocular delivery exhibit inadequate residence time, which often requires multiple daily dosing that may result in patient non-adherence. In this study, the development of a once-daily-dosed chitosan-coated metronidazole (MTZ)-loaded solid lipid nanoparticles (SLNs) for ocular delivery was undertaken. Melt emulsification and ultrasonication were used to manufacture MTZ-loaded SLN, which were subsequently coated with chitosan (CS) by mechanical stirring using a 0.1% w/v solution. Gelucire^® 48/16 and Transcutol^® HP were used as the solid lipid and synthetic solvent, respectively, with Tween^® 20 included as a stabilizing agent. The critical quality attributes (CQA) of the optimized CS-coated SLN that was monitored included particle size, polydispersity index, Zeta potential, % entrapment efficiency, % MTZ loading, pH, and osmolarity. The optimized coated nanocarriers were evaluated using laser Doppler anemometry (LDA) and were determined to be stable, with particle sizes in the nanometre range. In vitro mucoadhesion, MTZ release and short-term stability, in addition to the determination of the shape of the optimized CS-coated SLN, were undertaken. The mucoadhesive properties of the optimized CS-coated MTZ-loaded SLN demonstrated increased ocular availability, which may allow dose reduction or longer intervals between doses by improving precorneal retention and ocular availability. Overall, our findings suggest that CS-coated MTZ-loaded SLNs have the potential for clinical application, to enhance ocular delivery through the release of MTZ.

Amoxapine-Loaded Solid Lipid Nanoparticles with Superior Preclinical Pharmacokinetics for Better Brain Delivery: LC-MS/MS and GC-MS Analysis

The tricyclic antidepressant amoxapine (AMX) has been reported for a rapid onset of action compared to other cyclic antidepressants. It has very low solubility and bioavailability due to first-pass metabolism. Therefore, we planned to develop solid lipid nanoparticles (SLNs) of AMX using a single emulsification method to increase its solubility and bioavailability. HPLC and LC-MS/MS methods were developed further to quantify AMX in the formulation, plasma, and brain tissue samples. The formulation was studied for entrapment efficiency, loading, and in vitro drug release. Particle size and ζ potential analyses, AFM, SEM, TEM, DSC, and XRD were used for further characterization. In vivo oral pharmacokinetic and brain pharmacokinetic studies were performed using Wistar rats. The entrapment and loading efficiencies of AMX in SLNs were 85.8 ± 3.42 and 4.5 ± 0.45%, respectively. The developed formulation had a mean particle size of 151.5 ± 7.02 nm and a polydispersity index of 0.40 ± 0.11. DSC and XRD results indicated that AMX was incorporated into the nanocarrier system in an amorphous form. SEM, TEM, and AFM studies of AMX-SLNs confirmed the particles' spherical shape and nanoscale size. AMX solubility increased by approx. 2.67 times compared to the pure drug. The developed LC-MS/MS method was successfully applied to the oral and brain pharmacokinetic study of AMX-loaded SLNs in rats. Oral bioavailability was enhanced 1.6 times compared to the pure drug. The peak plasma concentrations of pure AMX and AMX-SLNs were 617.4 ± 137.4 and 1043.5 ± 150.2 (ng/mL), respectively. AMX-SLNs showed more than 5.8 times brain concentration compared to the pure drug. Based on the findings, it appears that utilizing a solid lipid nanoparticle carrier to transport AMX can be a highly effective delivery method with improved pharmacokinetic properties in the brain. This approach may prove valuable for future antidepressant treatment.

Nanomedicine strategies to improve therapeutic agents for the prevention and treatment of preterm birth and future directions

The World Health Organisation (WHO) estimates 15 million babies worldwide are born preterm each year, with 1 million infant mortalities and long-term morbidity in survivors. Whilst the past 40 years have provided some understanding in the causes of preterm birth, along with development of a range of therapeutic options, notably prophylactic use of progesterone or uterine contraction suppressants (tocolytics), the number of preterm births continues to rise. Existing therapeutics used to control uterine contractions are restricted in their clinical use due to pharmacological drawbacks such as poor potency, transfer of drugs to the fetus across the placenta and maternal side effects from activity in other maternal systems. This review focuses on addressing the urgent need for the development of alternative therapeutic systems with improved efficacy and safety for the treatment of preterm birth. We discuss the application of nanomedicine as a viable opportunity to engineer pre-existing tocolytic agents and progestogens into nanoformulations, to improve their efficacy and address current drawbacks to their use. We review different nanomedicines including liposomes, lipid-based carriers, polymers and nanosuspensions highlighting where possible, where these technologies have already been exploited e.g. liposomes, and their significance in improving the properties of pre-existing therapeutic agents within the field of obstetrics. We also highlight where active pharmaceutical agents (APIs) with tocolytic properties have been used for other clinical indications and how these could inform the design of future therapeutics or be repurposed to diversify their application such as for use in preterm birth. Finally we outline and discuss the future challenges.

Nose to Brain Delivery of Astaxanthin–Loaded Nanostructured Lipid Carriers in Rat Model of Alzheimer’s Disease: Preparation, in vitro and in vivo Evaluation

Background

Astaxanthin (AST) is a second-generation antioxidant with anti-inflammatory and neuroprotective properties and could be a promising candidate for Alzheimer's disease (AD) therapy, but is shows poor oral bioavailability due to its high lipophilicity.

Purpose

This study aimed to prepare and evaluate AST-loaded nanostructured lipid carriers (NLCs), for enhanced nose-to-brain drug delivery to improve its therapeutic efficacy in rat model of AD.

Methods

AST-NLCs were prepared using hot high-pressure homogenization technique, and processing parameters such as total lipid-to-drug ratio, solid lipid-to-liquid lipid ratio, and concentration of surfactant were optimized.

Results

The optimized AST-NLCs had a mean particle size of 142.8 ± 5.02 nm, polydispersity index of 0.247 ± 0.016, zeta potential of -32.2 ± 7.88 mV, entrapment efficiency of 94.1 ± 2.46%, drug loading of 23.5 ± 1.48%, and spherical morphology as revealed by transmission electron microscopy. Differential scanning calorimetry showed that AST was molecularly dispersed in the NLC matrix in an amorphous state, whereas Fourier transform infrared spectroscopy indicated that there is no interaction between AST and lipids. AST displayed a biphasic release pattern from NLCs; an initial burst release followed by sustained release for 24 h. AST-NLCs were stable at 4-8 ±2°C for six months. Intranasal treatment of AD-like rats with the optimized AST-NLCs significantly decreased oxidative stress, amyloidogenic pathway, neuroinflammation and apoptosis, and significantly improved the cholinergic neurotransmission compared to AST-solution. This was observed by the significant decline in the levels of malondialdehyde, nuclear factor-kappa B, amyloid beta (Aβ_1‑42), caspase-3, acetylcholinesterase, and β-site amyloid precursor protein cleaving enzyme-1 expression, and significant increase in the contents of acetylcholine and glutathione after treatment with AST-NLCs.

Conclusion

NLCs enhanced the intranasal delivery of AST and significantly improved its therapeutic properties.

Hybrid Magnetic Lipid-Based Nanoparticles for Cancer Therapy

Cancer is one of the major public health problems worldwide. Despite the advances in cancer therapy, it remains a challenge due to the low specificity of treatment and the development of multidrug resistance mechanisms. To overcome these drawbacks, several drug delivery nanosystems have been investigated, among them, magnetic nanoparticles (MNP), especially superparamagnetic iron oxide nanoparticles (SPION), which have been applied for treating cancer. MNPs have the ability to be guided to the tumor microenvironment through an external applied magnetic field. Furthermore, in the presence of an alternating magnetic field (AMF) this nanocarrier can transform electromagnetic energy in heat (above 42 °C) through Néel and Brown relaxation, which makes it applicable for hyperthermia treatment. However, the low chemical and physical stability of MNPs makes their coating necessary. Thus, lipid-based nanoparticles, especially liposomes, have been used to encapsulate MNPs to improve their stability and enable their use as a cancer treatment. This review addresses the main features that make MNPs applicable for treating cancer and the most recent research in the nanomedicine field using hybrid magnetic lipid-based nanoparticles for this purpose.

Folic Acid Functionalized Diallyl Trisulfide-Solid Lipid Nanoparticles for Targeting Triple Negative Breast Cancer

DATS (diallyl trisulfide), an anti-oxidant and cytotoxic chemical derived from the plant garlic, has been found to have potential therapeutic activity against triple-negative breast cancer (TNBC). Its hydrophobicity, short half-life, lack of target selectivity, and limited bioavailability at the tumor site limit its efficacy in treating TNBC. Overexpression of the Folate receptor on the surface of TNBC is a well-known target receptor for overcoming off-targeting, and lipid nanoparticles solve the limitations of limited bioavailability and short half-life. In order to overcome these constraints, we developed folic acid (FA)-conjugated DATS-SLNs in this research. The design of experiment (DoE) method was employed to optimize the FA-DATS-SLNs' nanoformulation, which resulted in a particle size of 168.2 ± 3.78 nm and a DATS entrapment of 71.91 ± 6.27%. The similarity index between MCF-7 and MDA-MB-231 cell lines demonstrates that FA-DATS-SLNs are more therapeutically efficacious in the treatment of aggravating TNBC. Higher cellular internalization and efficient Bcl2 protein downregulation support the hypothesis that functionalization of the FA on the surface of DATS-SLNs improves anticancer efficacy when compared with DATS and DATS-SLNs. FA-functionalized DATS-SLNs have demonstrated to be a promising therapeutic strategy for TNBC management.

Optimization of Gefitinib-Loaded Nanostructured Lipid Carrier as a Biomedical Tool in the Treatment of Metastatic Lung Cancer

Gefitinib (GEF) is utilized in clinical settings for the treatment of metastatic lung cancer. However, premature drug release from nanoparticles in vivo increases the exposure of systemic organs to GEF. Herein, nanostructured lipid carriers (NLC) were utilized not only to avoid premature drug release but also due to their inherent lymphatic tropism. Therefore, the present study aimed to develop a GEF-NLC as a lymphatic drug delivery system with low drug release. Design of experiments was utilized to develop a stable GEF-NLC as a lymphatic drug delivery system for the treatment of metastatic lung cancer. The in vitro drug release of GEF from the prepared GEF-NLC formulations was studied to select the optimum formulation. MTT assay was utilized to study the cytotoxic activity of GEF-NLC compared to free GEF. The optimized GEF-NLC formulation showed favorable physicochemical properties: <300 nm PS, <0.2 PDI, <−20 ZP values with >90% entrapment efficiency. Interestingly, the prepared formulation was able to retain GEF with only ≈57% drug release within 24 h. Furthermore, GEF-NLC reduced the sudden exposure of cultured cells to GEF and produced the required cytotoxic effect after 48 and 72 h incubation time. Consequently, optimized formulation offers a promising approach to improve GEF’s therapeutic outcomes with reduced systemic toxicity in treating metastatic lung cancer.

Solid Lipid Nanoparticles: Peculiar Strategy to Deliver Bio-Proactive Molecules

BACKGROUND

Novel Drug Delivery Systems (NDDS) provide numerous benefits compared to conventional dosage forms. Poor aqueous solubility, low bioavailability, frequent dosing, and particular hydrophilic lipophilic character of the drug are the biological factors associated with the traditional systems leading to the development of SLNs.

OBJECTIVE

For improving the solubility profile, enhancing the bioavailability, and attaining the best possible therapeutic effect of lipid inclined or aqueous inclined drug, formulating solid lipid nanoparticles is the best choice.

METHODS

Solid Lipid Nanoparticles (SLNs) have been projected as a colloidal carrier system with a size of 50-1,000 nm, collectively combining the benefits of other colloidal systems like liposomes, emulsions, etc., for delivering the drug at the target site. High absorption, high stability, and efficient drug packing enhance the pharmacokinetic and pharmacodynamic properties of the packed drug.

RESULT

Solid Lipid Nanoparticles can be developed in different dosage forms and administered via routes such as nasal, rectal, oral, topical, vaginal, ocular, and parenteral. They have higher physicochemical stability and the batch size can be easily scaled up at a low cost. Lipophilic as well as hydrophilic drugs can be easily incorporated into solid lipid nanoparticles.

CONCLUSION

In this manuscript, the authors have reviewed different aspects of solid lipid nanoparticles, major principles behind mechanism methods, recent patents, applications, and therapeutic potentials of solid lipid nanoparticles.

Recent Patents and Potential Applications of Homogenisation Techniques in Drug Delivery Systems

BACKGROUND

The term homogenise means "to force or provide coalesce". Homogenisation is a process to attain homogenous particle size. The objective of the homogenisation process is to use fluid force to split the fragments or tiny particles contained in the fluids into very small dimensions and form a sustainable dispersion suitable for further production.

METHODS

The databases were collected through Scopus, google patent, science web, google scholar, PubMed on the concept of homogenisation. The data obtained were systematically investigated.

RESULTS

The present study focus on the use of the homogenisation in drug delivery system. The aim of homogenisation process is to achieve the particle size in micro-and nano- range as it affects the different parameters in the formulation and biopharmaceutical profile of the drug. The particle size reduction plays a key role in influencing drug dissolution and absorption. The reduced particle size enhances the stability and therapeutic efficacy of the drug. Homogenization technology ensures to achieve effective, clinically efficient and targeted drug delivery with the minimal side effect.

CONCLUSION

Homogenization technology has been shown to be an efficient and easy method of size reduction to increase solubility and bioavailability, stability of drug carriers. This article gives an overview of the process attributes affecting the homogenization process, the patenting of homogeniser types, design, the geometry of valves and nozzles and its role in drug delivery.

Melatonin loaded hybrid nanomedicine: DoE approach, optimization and in vitro study on diabetic retinopathy model

Melatonin (MEL) is a pleiotropic neurohormone of increasing interest as a neuroprotective agent in ocular diseases. Improving the mucoadhesiveness is a proposed strategy to increase the bioavailability of topical formulations. Herein, the design and optimization of MEL-loaded lipid-polymer hybrid nanoparticles (mel-LPHNs) using Design of Experiment (DoE) was performed. LPHNs consisted of PLGA-PEG polymer nanoparticles coated with a cationic lipid-shell. The optimized nanomedicine showed suitable size for ophthalmic administration (189.4 nm; PDI 0.260) with a positive surface charge (+39.8 mV), high encapsulation efficiency (79.8 %), suitable pH and osmolarity values, good mucoadhesive properties and a controlled release profile. Differential Scanning Calorimetry and Fourier-Transform Infrared Spectroscopy confirmed the encapsulation of melatonin in the systems and the interaction between lipids and polymer matrix. Biological evaluation in an in vitro model of diabetic retinopathy demonstrated enhanced neuroprotective and antioxidant activities of mel-LPHNs, compared to melatonin aqueous solution at the same concentration (0.1 and 1 μM). A modified Draize test was performed to assess the ocular tolerability of the formulation showing no signs of irritation. To the best our knowledge, this study reported for the first time the development of mel-LPHNs, a novel and safe hybrid platform suitable for the topical management of retinal diseases.

Fabrication of edible solid lipid nanoparticle from beeswax/propolis wax by spontaneous emulsification: Optimization, characterization and stability

In the current study, the production and characterization of novel solid lipid nanoparticles (SLNs) using safe/low-cost natural beeswax (BW) and propolis wax (PW) and by the simple and inexpensive assay of spontaneous emulsification were studied. To fabricate SLNs, the optimum levels of surfactant/oil ratio (SOR), stirring speed, and time were obtained based on minimum particle size (PS) and polydispersity index (PDI). Therefore, the optimal conditions to produce PW and BW nanoparticles were SOR of 1.26 and 2 under stirring speed of 1050 rpm for 20 min, leading to PS of 21.9 and 23.2 nm, respectively. The contact angle of 73.7° and 62.9° for BW and PW SLNs respectively, showed suitable hydrophilicity to stabilize oil-in-water (O/W) Pickering emulsions. Temperatures over 70 °C led to a drastic increment of PS in both types of SLNs. Upon nanoparticles drying, the utilization of cryoprotectants could cause less aggregation and better reconstitution.

Green Extraction of Annatto Seed Oily Extract and Its Use as a Pharmaceutical Material for the Production of Lipid Nanoparticles

This work developd nanomaterials formulated from annatto seed oily extract (ASE), myristic acid (tetradecanoic acid), and their fatty acid esters. The annatto seed oily extract was obtained using only soybean oil (ASE + SO) and Brazil nut oil (ASE + BNO). The UV/VIS analysis of the oily extracts showed three characteristic peaks of the bixin molecule at 430, 456 and 486 nm. The lipid nanoparticles obtained using myristic acid and ASE + BNO or only BNO showed better results than the oil soybean extract, i.e., the particle size was <200 nm, PDI value was in the range of 0.2−0.3, and had no visual physical instability as they kept stable for 28 days at 4 °C. Lipid nanoemulsions were also produced with esters of myristic acid and ASE + BNO. These fatty acid esters significantly influenced the particle size of nanoemulsions. For instance, methyl tetradecanoate led to the smallest particle size nanoemulsions (124 nm), homogeneous size distribution, and high physical stability under 4 and 32 °C for 28 days. This work demonstrates that the chemical composition of vegetable oils and myristic acid esters, the storage temperature, the chain length of fatty acid esters (FAE), and their use as co-lipids improve the physical stability of lipid nanoemulsions and nanoparticles from annatto seed oily extract.

Optimization, Characterization and In Vivo Evaluation of Mupirocin Nanocrystals for Topical Administration

Treatment of infectious skin conditions resulting from wounds and burns with topical antibiotics is challenging, particularly those caused by methicillin-resistant Staphylococcus aureus bacteria (MRSA). This is due to the formation of bacterial biofilms characterized by antimicrobial resistance. Mupirocin (MP), a widely used topical antibiotic, is active against gram-positive bacteria including MRSA. However, MP suffers from sub-optimal therapeutic efficacy due to its poor water-solubility and the significant rise in MP-resistant S. aureus. In this study, the physico-chemical characteristics of MP were modified through nanocrystallization to improve its therapeutic efficacy for the treatment of skin infections. Mupirocin-nanocrystals (MP-NC) were prepared using a nanoprecipitation technique and optimized using a D-optimal response surface design. The optimization of MP-NC produced ultra-small monodisperse spherical particles with a mean diameter of 70 nm and a polydispersity index of 0.2. The design resulted in two optimal MP-NC formulations that were evaluated by performing series of in vitro, ex vivo, microbiological, and in vivo studies. In-vitro results showed a 10-fold increase in the saturation solubility and a 9-fold increase in the dissolution rate of MP-NC. Ex vivo permeation studies, using pig ears skin, showed a 2-fold increase in the dermal deposition of MP-NC with the highest drug deposition occurring at 500-µm skin depth. Moreover, the optimal MP-NC formulations were lyophilized and incorporated into a 2% w/w cream. Microbiological studies revealed a 16-fold decrease in the minimum inhibitory concentration and the minimum bactericidal concentration of MP-NC. In vivo studies, using a rat excision burn wound model, demonstrated rapid and complete healing of infected burn wounds in rats treated with MP-NC cream in comparison to marketed Avoban ointment. Our results suggest that nanocrystallization of MP may provide an avenue through which higher levels of a topically applied MP can be permeated into the skin to reach relevant infectious areas and exert potential local antibacterial effects.

Nanostructured lipid carriers loaded with an association of minoxidil and latanoprost for targeted topical therapy of alopecia

Alopecia is a condition associated with different etiologies, ranging from hormonal changes to chemotherapy, that affects over 80 million people in the USA. Nevertheless, there are currently few FDA-approved drugs for topical treatment, and existing formulations still present skin irritation issues, compromising treatment adherence. This work aimed to develop a safe formulation based on nanostructured lipid carriers (NLC) that entrap an association of minoxidil and latanoprost and target drug delivery to the hair follicles. To do so, thermal techniques combined with FTIR were used to assess the chemical compatibility of the proposed drug association. Then, NLC with 393.5 ± 36.0 nm (PdI<0.4) and +22.5 ± 0.2 mV zeta potential were produced and shown to entrap 86.9% of minoxidil and 99.9% of latanoprost efficiently. In vitro, the free drug combination was indicated to exert positive effects over human primary epidermal keratinocytes, supporting cell proliferation, migration and inducing the mRNA expression of MKI67 proliferation marker and VEGF - a possible effector for minoxidil-mediated hair growth. Interestingly, such a favorable drug combination profile was optimized when delivered using our NLC. Furthermore, according to the HET-CAM and reconstructed human epidermis assays, the nanoformulation was well tolerated. Finally, drug penetration was evaluated in vitro using porcine skin. Such experiments indicated that the NLC could be deposited preferentially into the hair follicles, causing a considerable increase in the penetration of the two drugs in such structures, compared to the control (composed of the free compounds) and generating a target-effect of approximately 50% for both drugs. In summary, present results suggest that hair follicle-targeted delivery of the minoxidil and latanoprost combination is a promising alternative to treat alopecia.

Liposomes as Carriers for the Delivery of Efavirenz in Combination with Glutathione—An Approach to Combat Opportunistic Infections

Human immunodeficiency virus (HIV)-infected individuals display an enhanced production of reactive oxygen species (ROS). This reduction of antioxidant capacity in host tissues has been related to the decrease in total levels of ROS scavengers such as glutathione (GSH). Prevention of opportunistic infections due to a weakened immune system is becoming a key strategy along with HIV elimination. Research in these directions is clearly warranted, especially a combination of antiretrovirals and antioxidants to ameliorate oxidative stress, improve intracellular uptake and target viral reservoirs. Hence, we aimed to formulate liposomes loaded with the antiretroviral drug efavirenz (EFA) in the presence of glutathione, as these carriers can be engineered to enhance the ability to reach the target reservoirs. The goal of the present work was to investigate the intracellular uptake of EFA-loaded liposome (with and without GSH) by human monocytic leukemia cells (THP-1 cells) and examine cell viability and ROS scavenging activity. Results obtained provided significant data as follows: (i) treatment with EFA and GSH combination could enhance the uptake and reduce cytotoxicity; (ii) encapsulation of EFA into liposomes increased its levels in the macrophages, which was further enhanced in the presence of GSH; (iii) delivery of EFA in the presence of GSH quenched the intracellular ROS, which was significantly higher when delivered via liposomes. Data revealed that a combination of EFA and GSH encompasses advantages; hence, GSH supplementation could be a safe and cost-effective treatment to slow the development of HIV infection and produce an immune-enhancing effect.

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.

Formula Development of Red Palm (Elaeis guineensis) Fruit Extract Loaded with Solid Lipid Nanoparticles Containing Creams and Its Anti-Aging Efficacy in Healthy Volunteers

Palm fruits (Elaeis guineensis) comprise antioxidants that can be used as skin care agents. This study developed a cosmeceutical cream containing E. guineensis extract, loaded with solid lipid nanoparticles (SLNs), and assessed its efficacy on female volunteers. The E. guineensis extract exhibited a good antioxidant activity with high levels of vitamin E, β-carotene, and palmitic acid. Day and night creams containing E. guineensis fruit extract, loaded with SLNs, were formulated and exhibited acceptable physical characteristics and good stability. Subsequently, their clinical efficacy and safety were evaluated on female volunteers. Both creams were non-irritating and had good cutaneous compatibility. Skin hydration, transepidermal water loss (TEWL), skin elasticity, melanin index, and skin texture were measured before and 30 min after the first application, as well as after 7, 14, and 30 days of daily application. A satisfactory survey was implemented using a questionnaire, and volunteer satisfaction scores were high for the product’s performance. Overall, the results showed that skin hydration, TEWL, cutaneous elasticity, and melanin index were improved, compared to the baseline data, after 30 days. Thus, the formulated facial day and night creams made the skin moist, reduced wrinkles, increased elasticity, and cleared the skin to the consumers’ satisfaction.

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.

Oral delivery of solid lipid nanoparticles: underlining the physicochemical characteristics and physiological condition affecting the lipolysis rate

INTRODUCTION

Lipid-based nano-drug delivery systems (LBNDDSs) have gained widespread attention in oral drug delivery due to their tunable and versatile properties such as biocompatibility and biodegradability, which makes them promising delivery systems for a variety of therapeutics. Currently, different types of LBNDDSs including liposomes, micelles, nanoemulsions, and solid lipid nanoparticles (SLNs) are developed for drug delivery applications. SLNs can be used as a controlled drug delivery system for oral delivery applications. However, its lipidic context makes that susceptible to lipolysis. The lipolysis rate of SLNs is affected by many factors that raise many questions for developing a more efficient delivery system.

AREAS COVERED

In the present work, we highlighted different factors affecting the digestion rate/level of SLNs in the gastrointestinal tract. This paper can be most useful for those researchers who are keen to develop a properly controlled drug delivery system based on SLNs for oral delivery applications.

EXPERT OPINION

SLNs can be used as a controlled drug delivery system for oral delivery applications. However, its lipidic context makes that susceptible to lipolysis. The lipolysis rate of SLNs is affected by many factors that raise many questions for developing a more efficient delivery system.

Development, characterization, molecular docking, and in vivo skin penetration of coenzyme Q10 nanostructured lipid carriers using tristearin and stearyl alcohol for dermal delivery

OBJECTIVES

This study aims to develop coenzyme Q10 nanostructured lipid carriers (NLCs) using tristearin and stearyl alcohol as well as isopropyl palmitate (IPP) as solid and liquid lipid respectively for the dermal delivery system.

METHODS

The coenzyme Q10 NLCs were optimized using tristearin, and stearyl alcohol in different concentrations and further characterized by dynamic light scattering (DLS) for particle size, polydispersity index (PDI), zeta potential, differential scanning calorimetry (DSC) and X-ray diffractometry for crystallinity behavior, Fourier transform infrared spectroscopy (FT-IR) for drug-lipid interaction, scanning electron microscopy (SEM) for particle shape, viscometer for viscosity, and pH meter for pH value. Furthermore, entrapment efficiency (EE), drug loading (DL), and skin penetration in vivo were also evaluated while molecular docking was conducted to examine the interaction between coenzyme Q10 and the lipids.

RESULTS

The coenzyme Q10 NLCs with tristearin-IPP and stearyl alcohol-IPP as lipid matrix had <1,000 nm particle size, <0.3 PDI, less negative than -30 mV zeta potential, about 41% crystallinity index, and about six as the pH value. Moreover, the EE, DL, viscosity, and in vivo skin penetration of the NLCs using tristearin were higher compared to stearyl alcohol, however, the skin penetration depths for both NLCs were not significantly different. Furthermore, the in silico binding energy of coenzyme Q10-tristearin was lower compared to coenzyme Q10-stearyl alcohol. Both of them showed hydrophobic and van der Waals interaction.

CONCLUSIONS

The NLCs of coenzyme Q10 were formulated successfully using tristearin-IPP and stearyl alcohol-IPP for dermal delivery.

Systematically designed chitosan-coated solid lipid nanoparticles of ferulic acid for effective management of Alzheimer's disease: A preclinical evidence

Ferulic acid (FA) is a ubiquitous natural plant bioactive with distinctive promise in neurodegenerative disorders. However, its therapeutic efficacy gets compromised owing to its poor aqueous solubility, inadequate permeability across lipophilic barriers, and extensive first-pass metabolism. The current studies, therefore, were undertaken to systematically develop chitosan-coated solid lipid nanoparticles (SLNs) using QbD paradigms for improved efficacy of FA in the management of Alzheimer's disease (AD). SLNs of FA were formulated employing Compritol as lipid and polysorbate 80 as surfactant and optimised using a 3² Central Composite Design (CCD). The optimized formulation, surface-coated with chitosan using ionic gelation, exhibited particle size of 185 nm, entrapment efficiency of 51.2 % and zeta potential of 12.4 mV. FTIR and DSC studies verified the compatibility of FA with formulation excipients, PXRD construed significant loss of drug crystallinity, while FESEM depicted existence of uniform spherical nanoparticles with little aggregation. Notable improvement in ex vivo mucoadhesion and permeation studies using goat nasal mucosa, coupled with extension in in vitro drug release, was obtained with SLNs. Substantial improvement with SLNs in cognitive ability through the reduction in escape latency time during behavioural studies, together with significant improvement in various biochemical parameters and body weight gain was observed in AD-induced rats. Histopathological images of different rat organs showed no perceptible change(s) in tissue morphology. Overall, these preclinical findings successfully demonstrate improved anti-AD efficacy, superior nasal mucoadhesion and permeation, extended drug release, improved patient compliance potential, safety and robustness of the developed lipidic nanoconstructs of FA through intranasal route.

Raloxifene-loaded SLNs with enhanced biopharmaceutical potential: QbD-steered development, in vitro evaluation, in vivo pharmacokinetics, and IVIVC

Raloxifene hydrochloride, a second-generation selective estrogen receptor modulator, has been approved for the management of breast cancer. However, it is known to exhibit poor (~ 2%) and inconsistent oral bioavailability in humans, primarily ascribable to its low aqueous solubility, extensive first-pass metabolism, P-gp efflux, and presystemic glucuronide conjugation. The present research work entails the systematic development and evaluation of SLNs of RLX for its enhanced biopharmaceutical performance against breast cancer. Factor screening studies were conducted using Taguchi design, followed by optimization studies employing Box-Behnken design. Preparation of SLNs was carried out using glyceryl monostearate and Compritol® 888 ATO (i.e., lipid), Phospholipid S-100 (i.e., co-surfactant), and TPGS-1000 (i.e., surfactant) employing solvent diffusion method. The optimized formulation was evaluated for zeta potential, average particle size, field emission scanning electron microscope, transmission electron microscopy, and in vitro release study. Further, MCF-7 cells (cell cytotoxicity assay, apoptosis assay, and reactive oxygen species assay) and Caco-2 cells (cell uptake studies and P-gp efflux assay) were employed to evaluate the in vitro anticancer potential of the developed optimized formulation. In vivo pharmacokinetic studies were conducted in Sprague-Dawley rats to evaluate the therapeutic profile of the developed formulation. The optimized SLN formulations exhibited a mean particle size of 109.7 nm, PDI 0.289 with a zeta potential of - 13.7 mV. In vitro drug dissolution studies showed Fickian release, with release exponent of 0.137. Cell cytotoxicity assay, apoptosis assay, and cellular uptake indicated 6.40-, 5.40-, and 3.18-fold improvement in the efficacy of RLX-SLNs vis-à-vis pure RLX. Besides, the pharmacokinetic studies indicated quite significantly improved biopharmaceutical performance of RLX-SLNs vis-à-vis pure drug, with 4.06-fold improvement in C_max, 4.40-fold in AUC_(0-72 h), 4.56-fold in AUC_(0-∞), 1.53-fold in K_a, 2.12-fold in t_1/2, and 1.22-fold in T_max. Further, for RLX-SLNs and pure drug, high degree of level A linear correlation was established between fractions of drug dissolved (in vitro) and of drug absorbed (in vivo) at the corresponding time-points. Stability studies indicated the robustness of RLX-SLNs when stored at for 3 months. Results obtained from the different studies construe promising the anticancer potential of the developed RLX-SLNs, thereby ratifying the lipidic nanocarriers as an efficient drug delivery strategy for improving the biopharmaceutical attributes of RLX.

Fabrication of Mupirocin-Loaded Nanostructured Lipid Carrier and Its In Vitro Characterization

In the present study, mupirocin (MP), an antimicrobial agent, was formulated as a nanostructured lipid carrier (NLC) by using a novel method named as melt emulsion ultrafiltration method. For the formulation of NLC, glyceryl monostearate and watermelon seed oil were used as solid and liquid lipids, respectively. The method was optimized for various parameters by Taguchi design of experiment and prepared NLCs were characterized for particle size, polydispersity index (PDI), shape, zeta potential, % drug loading, and in vitro release profile. The optimized NLCs were found to be smooth, monodisperse with PDI 0.229 ± 0.093. NLCs were found to have an average particle size of 139 ± 0.75 nm and +21.9 ± 0.98 mV as zeta potential. The % drug loading of optimized NLCs was found to be 59% ± 0.13%. The optimized NLCs were able to release the drug up to 24 h. The release kinetic study revealed mixed-order kinetics. Hence, it was concluded that the novel method is simple and able to fabricate MP-loaded NLCs with sustained release property and being stable in terms of particle size, PDI, and % drug loading.

Evaluation of Antitumor Efficacy of Chitosan-Tamarind Gum Polysaccharide Polyelectrolyte Complex Stabilized Nanoparticles of Simvastatin

PURPOSE

The present study was intended to fabricate chitosan (Ch)-tamarind gum polysaccharide (TGP) polyelectrolyte complex stabilized cubic nanoparticles of simvastatin and evaluate their potential against human breast cancer cell lines.

MATERIALS AND METHODS

The antisolvent precipitation method was used for formulation of nanoparticles. Factorial design (32) was utilized as a tool to analyze the effect of Ch and TGP concentration on particle size and entrapment efficiency of nanoparticles.

RESULTS

Formulated nanoparticles showed high entrapment efficiency (67.19±0.42-83.36±0.23%) and small size (53.3-383.1 nm). The present investigation involved utilization of two biological membranes (egg and tomato) as biological barriers for drug release. The study revealed that drug release from tomato membranes was retarded (as compared to egg membranes) but the release pattern matched that of egg membranes. All formulations followed the Baker-Lansdale model of drug release irrespective of the two different biological barriers. Stability studies were carried out for 45 days and exhibited less variation in particle size as well as a reduction in entrapment efficiency. Simvastatin loaded PEC stabilized nanoparticles exhibited better control on growth of human breast cancer cell lines than simple simvastatin. An unusual anticancer effect of simvastatin nanoparticles is also supported by several other research studies.

CONCLUSION

The present study involves first-time synthesis of Ch-TGP polyelectrolyte complex stabilized nanoparticles of simvastatin against MCF-7 cells. It recommends that, in future, theoretical modeling and IVIVC should be carried out for perfect designing of delivery systems.

Development and Evaluation of 1'-Acetoxychavicol Acetate (ACA)-Loaded Nanostructured Lipid Carriers for Prostate Cancer Therapy

1'-acetoxychavicol acetate (ACA) extracted from the rhizomes of Alpinia conchigera Griff (Zingiberaceae) has been shown to deregulate the NF-ĸB signaling pathway and induce apoptosis-mediated cell death in many cancer types. However, ACA is a hydrophobic ester, with poor solubility in an aqueous medium, limited bioavailability, and nonspecific targeting in vivo. To address these problems, ACA was encapsulated in a nanostructured lipid carrier (NLC) anchored with plerixafor octahydrochloride (AMD3100) to promote targeted delivery towards C-X-C chemokine receptor type 4 (CXCR4)-expressing prostate cancer cells. The NLC was prepared using the melt and high sheer homogenization method, and it exhibited ideal physico-chemical properties, successful encapsulation and modification, and sustained rate of drug release. Furthermore, it demonstrated time-based and improved cellular uptake, and improved cytotoxic and anti-metastatic properties on PC-3 cells in vitro. Additionally, the in vivo animal tumor model revealed significant anti-tumor efficacy and reduction in pro-tumorigenic markers in comparison to the placebo, without affecting the weight and physiological states of the nude mice. Overall, ACA-loaded NLC with AMD3100 surface modification was successfully prepared with evidence of substantial anti-cancer efficacy. These results suggest the potential use of AMD3100-modified NLCs as a targeting carrier for cytotoxic drugs towards CXCR4-expressing cancer cells.

Application of Fundamental Techniques for Physicochemical Characterizations to Understand Post-Formulation Performance of Pharmaceutical Nanocrystalline Materials

Nanocrystalline materials (NCM, i.e., crystalline nanoparticles) have become an important class of materials with great potential for applications ranging from drug delivery and electronics to optics. Drug nanocrystals (NC) and nano co-crystals (NCC) are examples of NCM with fascinating physicochemical properties and have attracted significant attention in drug delivery. NCM are categorized by advantageous properties, such as high drug-loading efficiency, good long-term physical stability, steady and predictable drug release, and long systemic circulation time. These properties make them excellent formulations for the efficient delivery of a variety of active pharmaceutical ingredients (API). In this review, we summarize the recent advances in drug NCM-based therapy options. Currently, there are three main methods to synthesize drug NCM, including top-down, bottom-up, and combination methods. The fundamental characterization methods of drug NCM are elaborated. Furthermore, the applications of these characterizations and their implications on the post-formulation performance of NCM are introduced.

Preparation, characterization, and in vivo evaluation of perphenazine-loaded nanostructured lipid carriers for oral bioavailability improvement

OBJECTIVE

The main scope of the present investigation was to improve the bioavailability of perphenazine (PPZ) by incorporating it into the nanostructured lipid carriers (NLCs).

SIGNIFICANCE

As a result of lipophilic nature and poor aqueous solubility, as well as extensive hepatic metabolism, PPZ has low systemic bioavailability via the oral route. NLCs have shown potentials to surmount the oral delivery drawbacks of poorly water-soluble drugs.

METHODS

The PPZ-NLCs were prepared by the emulsification-solvent evaporation method and subjected for particle size, zeta potential, and entrapment efficiency (EE) analysis. The optimized NLCs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffractometry (PXRD). Besides, in vitro release behavior, storage stability, and pharmacokinetic studies followed by a single-dose oral administration in rats were performed.

RESULTS

Optimized PPZ-NLCs showed a particle size of less than 180 nm with appropriate EE of more than 95%. Microscopic images captured with SEM and TEM exhibited that NLCs were approximately spherical in shape. DSC and PXRD analysis confirmed reduced crystallinity of PPZ after incorporation in NLCs. FTIR spectra demonstrated no chemical interactions between PPZ and NLC components. In vitro release studies confirmed the extended-release properties of NLC formulations. PPZ-NLCs exhibited good stability at 4 °C within three months. The oral bioavailability of NLC-6 and NLC-12 was enhanced about 3.12- and 2.49-fold, respectively, compared to the plain drug suspension.

CONCLUSION

NLC can be designated as an effective nanocarrier for oral delivery of PPZ.

Fabrication, characterization and optimization of nanostructured lipid carrier formulations using Beclomethasone dipropionate for pulmonary drug delivery via medical nebulizers

Aerosolization is a non-invasive approach in drug delivery for localized and systemic effect. Nanostructured lipid carriers (NLCs) are new generation versatile carriers, which offer protection from degradation and enhance bioavailability of poorly water soluble drugs. The aim of this study was to develop and optimize NLC formulations in combination with optimized airflow rates (i.e. 60 and 15 L/min) and choice of medical nebulizers including Air jet, Vibrating mesh and Ultrasonic nebulizer for superior aerosolization performance, assessed via a next generation impactor (NGI). Novel composition and combination of NLC formulations (F1 - F15) were prepared via ultrasonication method, employing five solid lipids (glycerol trimyristate (GTM), glycerol trilaurate (GTL), cetyl palmitate (CP), glycerol monostearate (GMS) and stearic acid (SA)); and three liquid lipids (glyceryl tributyrate (GTB), propylene glycol dicaprylate/dicaprate (PGD) and isopropyl palmitate (IPP)) in 1:3 w/w ratios (i.e. combination of one solid and one liquid lipid), with Beclomethasone dipropionate (BDP) incorporated as the model drug. Out of fifteen BDP-NLC formulations, the physicochemical properties of formulations F7, F8 and F10 exhibited desirable stability (one week at 25 °C), with associated particle size of ~241 nm, and >91% of drug entrapment. Post aerosolization, F10 was observed to deposit notably smaller sized particles (from 198 to 136 nm, 283 to 135 nm and 239 to 157 nm for Air jet, Vibrating mesh and Ultrasonic nebulizers, respectively) in all stages (i.e. from stage 1 to 8) of the NGI, when compared to F7 and F8 formulations. Six week stability studies conducted at 4, 25 and 45 °C, demonstrated F10 formulation stability in terms of particle size, irrespective of temperature conditions. Nebulizer performance study using the NGI for F10 identified the Air jet to be the most efficient nebulizer, depositing lower concentrations of BDP in the earlier stages (1-3) and higher (circa 82 and 85%) in the lateral stages (4-8) using 60 and 15 L/min airflow rates, when compared to the Vibrating mesh and Ultrasonic nebulizers. Moreover, at both airflow rates, the Air jet nebulizer elicited a longer nebulization time of ~42 min, facilitating aerosol inhalation for prophylaxis of asthma with normal tidal breathing. Based on characterization and nebulizer performance employing both 60 and 15 L/min airflow rates, the Air jet nebulizer offered enhanced performance, exhibiting a higher fine particle dose (FPD) (90 and 69 µg), fine particle fraction (FPF) (70 and 54%), respirable fraction (RF) (92 and 69%), and lower mass median aerodynamic diameter (MMAD) (1.15 and 1.62 µm); in addition to demonstrating higher drug deposition in the lateral parts of the NGI, when compared to its counterpart nebulizers. The F10 formulation used with the Air jet nebulizer was identified as being the most suitable combination for delivery of BDP-NLC formulations.

Nebulised surface-active hybrid nanoparticles of voriconazole for pulmonary Aspergillosis demonstrate clathrin-mediated cellular uptake, improved antifungal efficacy and lung retention

BACKGROUND

Incidence of pulmonary aspergillosis is rising worldwide, owing to an increased population of immunocompromised patients. Notable potential of the pulmonary route has been witnessed in antifungal delivery due to distinct advantages of direct lung targeting and first-pass evasion. The current research reports biomimetic surface-active lipid-polymer hybrid (LPH) nanoparticles (NPs) of voriconazole, employing lung-specific lipid, i.e., dipalmitoylphosphatidylcholine and natural biodegradable polymer, i.e., chitosan, to augment its pulmonary deposition and retention, following nebulization.

RESULTS

The developed nanosystem exhibited a particle size in the range of 228-255 nm and drug entrapment of 45-54.8%. Nebulized microdroplet characterization of NPs dispersion revealed a mean diameter of  ≤ 5 μm, corroborating its deep lung deposition potential as determined by next-generation impactor studies. Biophysical interaction of LPH NPs with lipid-monolayers indicated their surface-active potential and ease of intercalation into the pulmonary surfactant membrane at the air-lung interface. Cellular viability and uptake studies demonstrated their cytocompatibility and time-and concentration-dependent uptake in lung-epithelial A549 and Calu-3 cells with clathrin-mediated internalization. Transepithelial electrical resistance experiments established their ability to penetrate tight airway Calu-3 monolayers. Antifungal studies on laboratory strains and clinical isolates depicted their superior efficacy against Aspergillus species. Pharmacokinetic studies revealed nearly 5-, 4- and threefolds enhancement in lung AUC, Tmax, and MRT values, construing significant drug access and retention in lungs.

CONCLUSIONS

Nebulized LPH NPs were observed as a promising solution to provide effective and safe therapy for the management of pulmonary aspergillosis infection with improved patient compliance and avoidance of systemic side-effects.

Erlotinib entrapped in cholesterol-depleting cyclodextrin nanoparticles shows improved antitumoral efficacy in 3D spheroid tumors of the lung and the liver

Erlotinib (ERL), a tyrosine kinase inhibitor approved for therapeutic use in non-small cell lung cancer is further researched for eventual liver cancer treatment. However, conventional ERL has important bioavailability problems resulting from oral administration, poor solubility and gastrointestinal degradation into inactive metabolites. Alternative administration routes and nanoparticulate drug delivery systems are studied to prevent or reduce these drawbacks. In this study, ERL-loaded CD nanosphere and nanocapsule formulations capable of cholesterol depletion in resistant cancer cells were evaluated for ERL delivery. Drug loading and release profile depended largely on the surface charge of nanoparticles. Antiproliferative activity data obtained from 2D and 3D cell culture models demonstrated that polycationic βCD nanocapsules were the most effective formulation for ERL delivery to lung and liver cancer cells. 3D tumour tumoral penetration studies further revealed that nanocapsule formulations penetrated deeper into the tumour through the multilayered cells. Furthermore, all formulations were able to extract membrane cholesterol from lung and liver cancer cell lines, indicating the induction of apoptosis and overcoming drug resistance. In conclusion, given their tumoral penetration and cell membrane cholesterol depletion abilities, amphiphilic CD nanocapsules emerge as promising alternatives to improve the safety and efficiency of ERL treatment of both liver and lung tumours.

Nanomaterial Lipid-Based Carrier for Non-Invasive Capsaicin Delivery; Manufacturing Scale-Up and Human Irritation Assessment

Capsaicin is an active compound in chili peppers (Capsicum chinense) that has been approved for chronic pain treatment. The topical application of high-strength capsaicin has been proven to reduce pain; however, skin irritation is a major drawback. The aim of this study was to investigate an appropriate and scalable technique for preparing nanostructured lipid carriers (NLCs) containing 0.25% capsaicin from capsicum oleoresin (NLC_C) and to evaluate the irritation of human skin by chili-extract-loaded NLCs incorporated in a gel formulation (Gel NLC_C). High-shear homogenization with high intensity (10,000 rpm) was selected to create uniform nanoparticles with a size range from 106 to 156 nm. Both the NLC_C and Gel NLC_C formulations expressed greater physical and chemical stabilities than the free chili formulation. Release and porcine biopsy studies revealed the sustained drug release and significant permeation of the NLCs through the outer skin layer, distributing in the dermis better than the free compounds. Finally, the alleviation of irritation and the decrease in uncomfortable feelings following the application of the Gel NLC_C formulation were compared to the effects from a chili gel and a commercial product in thirty healthy volunteers. The chili-extract-loaded NLCs were shown to be applicable for the transdermal delivery of capsaicin whilst minimizing skin irritation, the major noncompliance cause of patients.

Biocompatibility of Biomaterials for Nanoencapsulation: Current Approaches

Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.

Injectable Lipid-Based Depot Formulations: Where Do We Stand?

The remarkable number of new molecular entities approved per year as parenteral drugs, such as biologics and complex active pharmaceutical ingredients, calls for innovative and tunable drug delivery systems. Besides making these classes of drugs available in the body, injectable depot formulations offer the unique advantage in the parenteral world of reducing the number of required injections, thus increasing effectiveness as well as patient compliance. To date, a plethora of excipients has been proposed to formulate depot systems, and among those, lipids stand out due to their unique biocompatibility properties and safety profile. Looking at the several long-acting drug delivery systems based on lipids designed so far, a legitimate question may arise: How far away are we from an ideal depot formulation? Here, we review sustained release lipid-based platforms developed in the last 5 years, namely oil-based solutions, liposomal systems, in situ forming systems, solid particles, and implants, and we critically discuss the requirements for an ideal depot formulation with respect to the used excipients, biocompatibility, and the challenges presented by the manufacturing process. Finally, we delve into lights and shadows originating from the current setups of in vitro release assays developed with the aim of assessing the translational potential of depot injectables.