Experimental design in formulation of diazepam nanoemulsions: physicochemical and pharmacokinetic performances

Nanoemulsions containing amphotericin b and paromomycin for the treatment of cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) is a vector-borne disease characterized by skin lesions that can evolve into high-magnitude ulcerated lesions. Thus, this study aimed to develop an innovative nanoemulsion (NE) with clove oil, Poloxamer® 407, and multiple drugs, such as amphotericin B (AmB) and paromomycin (PM), for use in the topical treatment of CL.

METHODS

Droplet size, morphology, drug content, stability, in vitro release profile, in vitro cytotoxicity on RAW 264.7 macrophages, and antileishmanial activity using axenic amastigotes of Leishmania amazonensis were assessed for NEs.

RESULTS

After optimizing the formulation parameters, such as the concentration of clove oil and drugs, using an experimental design, it was possible to obtain a NE with an average droplet size of 40 nm and a polydispersion index of 0.3, and these parameters were maintained throughout the 365 days. Furthermore, the NE showed stability of AmB and PM content for 180 days under refrigeration (4 °C), presented a pH compatible with the skin, and released modified AmB and PM. NE showed the same toxicity as free AmB and higher toxicity than free PM against RAW 264.7 macrophages. The same activity as free AmB, and higher activity than free PM against amastigotes L. amazonensis.

CONCLUSION

It is possible to develop a NE for the treatment of CL; however, complementary studies regarding the antileishmanial activity of NE should be carried out.

A critical review of the novelties in the development of intravenous nanoemulsions

Nanoemulsions have gained increasing attention in recent years as a drug delivery system due to their ability to improve the solubility and bioavailability of poorly water-soluble drugs. This systematic review aimed to collect and critically analyze recent novelties in developing, designing, and optimizing intravenous nanoemulsions appearing in articles published between 2017 and 2022. The applied methodology involved searching two electronic databases PubMed and Scopus, using the keyword "nanoemulsion" in combination with "intravenous" or "parenteral". The resulting original articles were classified by the method of preparation into different categories. An overview of the current methods used for the preparation of such formulations, including high- and low-energy emulsification, was provided. The advantages and disadvantages of these methods were discussed, as well as their potential impact on the properties of the developed intravenous nanoemulsions. The problem of inconsistency in intravenous nanoemulsion terminology may lead to misunderstandings and misinterpretations of their properties and applications was also undertaken. Finally, the regulatory aspects of intravenous nanoemulsions, the state of the art in the field of intravenous emulsifiers, and the future perspectives were presented.

Parenteral Lipid-Based Nanoparticles for CNS Disorders: Integrating Various Facets of Preclinical Evaluation towards More Effective Clinical Translation

Contemporary trends in combinatorial chemistry and the design of pharmaceuticals targeting brain disorders have favored the development of drug candidates with increased lipophilicity and poorer water solubility, with the expected improvement in delivery across the blood-brain barrier (BBB). The growing availability of innovative excipients/ligands allowing improved brain targeting and controlled drug release makes the lipid nanocarriers a reasonable choice to overcome the factors impeding drug delivery through the BBB. However, a wide variety of methods, study designs and experimental conditions utilized in the literature hinder their systematic comparison, and thus slows the advances in brain-targeting by lipid-based nanoparticles. This review provides an overview of the methods most commonly utilized during the preclinical testing of liposomes, nanoemulsions, solid lipid nanoparticles and nanostructured lipid carriers intended for the treatment of various CNS disorders via the parenteral route. In order to fully elucidate the structure, stability, safety profiles, biodistribution, metabolism, pharmacokinetics and immunological effects of such lipid-based nanoparticles, a transdisciplinary approach to preclinical characterization is mandatory, covering a comprehensive set of physical, chemical, in vitro and in vivo biological testing.

Curcumin Loaded PEGylated Nanoemulsions Designed for Maintained Antioxidant Effects and Improved Bioavailability: A Pilot Study on Rats

The current study describes the experimental design guided development of PEGylated nanoemulsions as parenteral delivery systems for curcumin, a powerful antioxidant, as well as the evaluation of their physicochemical characteristics and antioxidant activity during the two years of storage. Experimental design setup helped development of nanoemulsion templates with critical quality attributes in line with parenteral application route. Curcumin-loaded nanoemulsions showed mean droplet size about 105 nm, polydispersity index <0.15, zeta potential of -40 mV, and acceptable osmolality of about 550 mOsm/kg. After two years of storage at room temperature, all formulations remained stable. Moreover, antioxidant activity remained intact, as demonstrated by DPPH (IC50 values 0.078-0.075 mg/mL after two years) and FRAPS assays. In vitro release testing proved that PEGylated phospholipids slowed down the curcumin release from nanoemulsions. The nanoemulsion carrier has been proven safe by the MTT test conducted with MRC-5 cell line, and effective on LS cell line. Results from the pharmacokinetic pilot study implied the PEGylated nanoemulsions improved plasma residence of curcumin 20 min after intravenous administration, compared to the non-PEGylated nanoemulsion (two-fold higher) or curcumin solution (three-fold higher). Overall, conclusion suggests that developed PEGylated nanoemulsions present an acceptable delivery system for parenteral administration of curcumin, being effective in preserving its stability and antioxidant capacity at the level highly comparable to the initial findings.

Inhibition of aldehyde dehydrogenase by furazolidone nanoemulsion to decrease cisplatin resistance in lung cancer cells

Aim: The overexpression of aldehyde dehydrogenase (ALDH) in cancer cells contributes to therapeutic resistance. Furazolidone (FUR) is a strong ALDH inhibitor. Methods: FUR nanoemulsion (NE) was formulated and tested for ALDH inhibitory activity in comparison with free FUR. The cytotoxic potential of cisplatin was evaluated in combination with free FUR and FUR NE. Results: The optimized FUR NE showed droplet size of 167.9 ± 3.1 nm and drug content of 84.2 ± 2.3%. FUR NE inhibited 99.75 ± 2.1% of ALDH activity while 25.0 ± 4.6% was inhibited by free FUR. FUR NE increased the sensitivity to cisplatin in A549 cells by more than tenfold by its ALDH inhibitory effects. Conclusion: This finding can be a promising approach to improve cancer survival in ALDH-positive drug-resistant cancers.

Oral Nanoemulsion of Fenofibrate: Formulation, Characterization, and In Vitro Drug Release Studies

Nanoemulsions (NMs) are one of the most important colloidal dispersion systems that are primarily used to improve the solubility of poorly water soluble drugs. The main objectives of this study were, first, to prepare an NM loaded with fenofibrate using a high shear homogenization technique and, second, to study the effect of variable using a central composite design. Twenty batches of fenofibrate-loaded NM formulations were prepared. The formed NMs were subjected to droplet size analysis, zeta potential, entrapment efficiency, pH, dilution, polydispersity index, transmission electron microscopy (TEM), Fourier transform infrared spectrophotometry, differential scanning calorimetry (DSC), and in vitro drug release study. Analysis of variance was used for entrapment efficiency data to study the fitness and significance of the design. The NM-7 batch formulation demonstrated maximum entrapment efficiency (81.82%) with lowest droplet size (72.28 nm), and was thus chosen as the optimized batch. TEM analysis revealed that the NM was well dispersed with droplet sizes <100 nm. Incorporation of the drug into the NM was confirmed with DSC studies. In addition, the batch NM-7 also showed the maximum in vitro drug release (87.6%) in a 0.05 M sodium lauryl sulfate solution. The release data revealed that the NM followed first-order kinetics. The outcomes of the study revealed the development of a stable oral NM containing fenofibrate using the high shear homogenization technique. This approach may aid in further enhancing the oral bioavailability of fenofibrate, which requires further in vivo studies.

Nanoemulsion: A Novel Drug Delivery Approach for Enhancement of Bioavailability

BACKGROUND

Poor bioavailability and solubility of drugs in aqueous phase are the most important problems of newly developed chemical entities that can be improved by nanoemulsion.

OBJECTIVES

BCS class II and IV which are poorly soluble in water demonstrate various problems in conventional dosage forms. For the improvement of solubility, bioavailability and getting the best therapeutic effect of poorly soluble drugs nanoemulsion is the best solution.

METHODS

Nanoemulsion are thermodynamically unstable isotropic system with droplet size 1-100 nm in which two immiscible fluids are combined together to form one phase by using an emulsifying agent. Nanoemulsion can be designed to promote the bioavailability of API by trapping them inside.

RESULTS

Nanoemulsion can be developed in many dosage forms such as oral, parenteral, topical, ophthalmic dosage form in large scale using common operation at a very low cost. Large range of lipophilic drugs can be easily incorporated in nanoemulsion.

CONCLUSION

In this review, attention is focused on the type of nanoemulsions, their advantages over other dosage form, method for their preparation, characterization, applications and patents in various fields.

Oral delivery of fish oil in oil-in-water nanoemulsion: development, colloidal stability and modulatory effect on in vivo inflammatory induction in mice

To improve the oral absorption of fish oil and test its anti-inflammatory effect, a fish oil nanoemulsion was developed using cis-4,7,10,13,16,19-docosahexaenoic fatty acid as a biomarker for oral administration. The colloidal stability tests of the fish oil nanoemulsion showed an average size of 155.44 nm ± 6.46 (4 °C); 163.04 nm ± 9.97 (25 °C) and polydispersity index 0.22 ± 0.02 (4 °C), 0.21 ± 0.02 (25 °C), indicating systems with low polydispersity and stable droplets. The fish oil nanoemulsion did not alter the cell viability of the RAW 264.7 macrophages and, at a concentration of 0.024 mg/mL, was kinetically incorporated into the cells after 18 h of contact. The nanoemulsion was maintained in the gastrointestinal region for a significantly shorter period of time (p ≤ 0.05) compared to the intake of fish oil in free form. Inflammatory tests demonstrated that nanoemulsion and fish oil showed less (p ≤ 0.05) neutrophil infiltration after 24h of sepsis induction and there was a significant reduction (p ≤ 0.05) in the volume of paw edema in female adult Balb/c mice who received the nanoemulsion diet compared to the other experimental groups (control, formalin, fish oil and sunflower oil). These results indicate that the fish oil nanoemulsion was significantly effective in the dietary conditions tested here, presenting satisfactory responses in the modulation of inflammatory disorders, demonstrating interesting and beneficial nutraceutical effects.

Nanomedicine: a new paradigm to overcome drug incompatibilities

OBJECTIVES

Drug incompatibilities may compromise the safety and effectiveness of combined drugs and result in mild-to-serious clinical complications, such as catheter obstruction, loss of drug efficacy, formation of toxic derivatives and embolism. Various preventive strategies have been implemented to overcome drug incompatibilities with limited success. This review presents an innovative approach to prevent drug incompatibilities via isolating the incompatible drugs into nanostructures.

KEY FINDINGS

Several examples of incompatible drugs may be loaded separately into nanostructures of various types. Physicochemical characteristics and biocompatibility of the nanomaterials that are being utilized to prevent physicochemical incompatibilities should be carefully considered.

CONCLUSIONS

There is a new era of exploiting nanomaterials in overcoming various types of physicochemical incompatibilities, with additional benefits of further improvements in pharmacokinetic profiles and pharmacological actions of the administered drugs.

Factors impacting lipid digestion and nutraceutical bioaccessibility assessed by standardized gastrointestinal model (INFOGEST): oil

INFOGEST gastrointestinal model used to study impact of oil droplet size on digestion and bioaccessibility.

Development Insights of Surface Modified Lipid Nanoemulsions of Dihydroartemisinin for Malaria Chemotherapy: Characterization, and in vivo Antimalarial Evaluation

BACKGROUND

The use of dihydroartemisinin (DHA) for effective malaria treatment is challenged by its poor aqueous solubility and inadequate bioavailability leading to treatment failures and emergence of resistant strains. A review of some novel drug delivery systems developed to address these challenges and their patents revealed that no study has reported the application of surface modified lipid nanoemulsions for improved antimalarial activity of DHA.

OBJECTIVE

The main thrust of this study is to develop oral dihydroartemisinin formulations solubilized in surface modified lipid nanoemulsions, characterize, and evaluate their activity against murine malaria.

METHOD

Lipid nanoemulsions containing dihydroartemisinin were formulated by high pressure homogenization using soybean oil, and polyethylene glycol 4000 was employed for surface modification. The formulations were characterized for droplet size, surface charge, pH, fouriertransform infrared spectroscopy, and surface morphology, viscosity and drug content efficiency. In vitro haemolytic study as a function of cytotoxicity using red blood cells as well as in vivo anti-malarial study using murine malaria model was also investigated.

RESULTS

Nanoemulsions recorded droplet sizes ranging from 26 - 56 nm, and zeta potential in the range of -28 to -35 mV. The formulations were slightly acidic (pH 4.4 - 5.8) with the drug molecularly dispersed as seen using infrared spectroscopy. The formulations showed non- Newtonian flow with significant drug content efficiency in the range of 77-96%. The formulations did not induce haemolysis of cells and showed good clearance of parasitaemia.

CONCLUSION

Surface-modified lipid nanoemulsion is a perfect carrier system for improving the anti-malarial activity of dihydroartemisinin.

Vitamin E Loaded Naringenin Nanoemulsion via Intranasal Delivery for the Management of Oxidative Stress in a 6-OHDA Parkinson's Disease Model

Purpose

The present study is an attempt to develop a vitamin E loaded naringenin (NRG) Nanoemulsion (NE) for direct nose-to-brain delivery for better management of Parkinson's disease (PD).

Methods

The optimized NE was evaluated for efficacy in PD using multiple behavioral studies (including narrow beam test, muscular coordination test, grip strength test, forced swimming test, and akinesia test) in a rat model. Optimized formulation was evaluated for droplet size, polydispersity index (PDI), refractive index, transmittance, zeta potential, and viscosity.

Results

Optimized NE had a droplet size of 38.70 ± 3.11nm, PDI of 0.14 ± 0.0024, refractive index of 1.43 ± 0.01, transmittance of 98.12 ± 0.07 %, zeta potential of − 27.4 ± 0.14 mV, and viscosity of 19.67 ± 0.25 Pa s. Behavioral studies showed that 6-OHDA induced PD in rats were successfully reversed when administered with NRG NE intranasally along with the levodopa. While the levels of GSH and SOD were significantly higher, levels of MDA were significantly lower in the group treated with NRG NE via intranasal route along with levodopa.

Conclusion

Encouraging results from current study provide evidence for possible efficacy of a novel noninvasive intranasal delivery system of NRG for management of PD related symptoms.

Nanoemulsions in CNS drug delivery: recent developments, impacts and challenges

Despite enormous efforts, treatment of CNS diseases remains challenging. One of the main issues causing this situation is limited CNS access for the majority of drugs used as part of the therapeutic regimens against life-threatening CNS diseases. Regarding the inarguable position of the nanocarrier systems in neuropharmacokinetic enhancement of the CNS drugs, this review discusses the latest findings on nanoemulsions (NEs) as one of the most promising candidates of this type, to overcome the challenges of CNS drug delivery. Future development of NE-based CNS drug delivery needs to consider so many aspects not only from a physicochemical point of view but also related to the biointerface of these very small droplets before achieving clinical value.

Evaluation of lipid-stabilised tripropionin nanodroplets as a delivery route for combretastatin A4

Lipid-based nanoemulsions are a cheap and elegant route for improving the delivery of hydrophobic drugs. Easy and quick to prepare, nanoemulsions have promise for the delivery of different therapeutic agents. Although multiple studies have investigated the effects of the oil and preparation conditions on the size of the nanoemulsion nanodroplets for food applications, analogous studies for nanoemulsions for therapeutic applications are limited. Here we present a study on the production of lipid-stabilised oil nanodroplets (LONDs) towards medical applications. A number of biocompatible oils were used to form LONDs with phospholipid coatings, and among these, squalane and tripropionin were chosen as model oils for subsequent studies. LONDs were formed by high pressure homogenisation, and their size was found to decrease with increasing production pressure. When produced at 175MPa, all LONDs samples exhibited sizes between 100 and 300nm, with polydispersity index PI between 0.1 and 0.3. The LONDs were stable for over six weeks, at 4°C, and also under physiological conditions, showing modest changes in size (<10%). The hydrophobic drug combretastatin A4 (CA4) was encapsulated in tripropionin LONDs with an efficiency of approximately 76%, achieving drug concentration of approximately 1.3mg/ml. SVR mouse endothelial cells treated with CA4 tripropionin LONDs showed the microtubule disruption, characteristic of drug uptake for all tested doses, which suggests successful release of the CA4 from the LONDs.

Design Expert(®) supported optimization and predictive analysis of selegiline nanoemulsion via the olfactory region with enhanced behavioural performance in Parkinson's disease

Selegiline is a monoamine oxidase B (MAO-B) inhibitor and is used in the treatment of Parkinson's disease. The main problem associated with its oral administration is its low oral bioavailability (10%) due to its poor aqueous solubility and extensive first pass metabolism. The aim of the present research work was to develop a nanoemulsion loaded with selegiline for direct nose-to-brain delivery for the better management of Parkinson's disease. A quality by design (QbD) approach was used in a statistical multivariate method for the preparation and optimization of nanoemulsion. In this study, four independent variables were chosen, in which two were compositions and two were process variables, while droplet size, transmittance, zeta potential and drug release were selected as response variables. The optimized formulation was assessed for efficacy in Parkinson's disease using behavioural studies, namely forced swimming, locomotor, catalepsy, muscle coordination, akinesia and bradykinesia or pole test in Wistar rats. The observed droplet size, polydispersity index (PDI), refractive index, transmittance, zeta potential and viscosity of selegiline nanoemulsion were found to be 61.43 ± 4.10 nm, 0.203 ± 0.005, 1.30 ± 0.01, 99.80 ± 0.04%, -34 mV and 31.85 ± 0.24 mPas respectively. Surface characterization studies demonstrated a spherical shape of nanoemulsion which showed 3.7 times enhancement in drug permeation as compared to drug suspension. The results of behaviour studies showed that treatment of haloperidol induced Parkinson's disease in rats with selegiline nanoemulsion (administered intranasally) showed significant improvement in behavioural activities in comparison to orally administered drug. These findings demonstrate that nanoemulsion could be a promising new drug delivery carrier for intranasal delivery of selegiline in the treatment of Parkinson's disease.

Development, Optimization, and Characterization of PEGylated Nanoemulsion of Prostaglandin E1 for Long Circulation

Lipo-PGE1 is the most widely used formulation of PGE1 in clinic. However, PGE1 is easier to leak out from lipo-PGE1 and this will lead to the phlebophlogosis when intravenous injection. The stability of lipo-PGE1 in storage and in vivo is also discounted. The aim of this study is to develop a long-circulating prostaglandin E1-loaded nanoemulsion modified with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG) to improve the stability and pharmacokinetics profiles of lipo-PGE1. PEGylated PGE1 nanoemulsion was prepared using a dispersing-homogenized method. The stability of nanoemulsion in 1 month was investigated. Pharmacokinetic studies were employed to evaluate the in vivo profile of the optimized nanoemulsion. The optimized nanoemulsion PGE1-PEG2000(1%)-NE showed an oil droplet size <100 nm with a surface charge of -14 mV. Approximately, 97% of the PGE1 was encapsulated in the nanoemulsion. The particle size, zeta potential, and drug loading of PGE1-PEG2000(1%)-NE were stable in 1 month. After PGE1-PEG2000(1%)-NE was intravenously administered to rats, the area under curve (AUC) and half-life of PGE1 were, respectively, 1.47-fold and 5.98-fold higher than those of lipo-PGE1 (commercial formulation). PGE1-PEG2000(1%)-NE was an ideal formulation for prolonging the elimination time of PGE1. This novel parenteral colloidal delivery system of PGE1 has a promising potential in clinic use.

Biocompatible Nanoemulsions for Improved Aceclofenac Skin Delivery: Formulation Approach Using Combined Mixture-Process Experimental Design

We aimed to develop lecithin-based nanoemulsions intended for effective aceclofenac (ACF) skin delivery utilizing sucrose esters [sucrose palmitate (SP) and sucrose stearate (SS)] as additional stabilizers and penetration enhancers. To find the suitable surfactant mixtures and levels of process variables (homogenization pressure and number of cycles - high pressure homogenization manufacturing method) that result in drug-loaded nanoemulsions with minimal droplet size and narrow size distribution, a combined mixture-process experimental design was employed. Based on optimization data, selected nanoemulsions were evaluated regarding morphology, surface charge, drug-excipient interactions, physical stability, and in vivo skin performances (skin penetration and irritation potential). The predicted physicochemical properties and storage stability were proved satisfying for ACF-loaded nanoemulsions containing 2% of SP in the blend with 0%-1% of SS and 1%-2% of egg lecithin (produced at 50°C/20 cycles/800 bar). Additionally, the in vivo tape stripping demonstrated superior ACF skin absorption from these nanoemulsions, particularly from those containing 2% of SP, 0.5% of SS, and 1.5% of egg lecithin, when comparing with the sample costabilized by conventional surfactant - polysorbate 80. In summary, the combined mixture-process experimental design was shown as a feasible tool for formulation development of multisurfactant-based nanosized delivery systems with potentially improved overall product performances.

Drug delivery and drug targeting with parenteral lipid nanoemulsions - A review

Lipid nanosized emulsions or nanoemulsions (NE) are oil in water dispersions with an oil droplet size of about 200nm. This size of oil droplets dispersed in a continuous water phase is a prerequisite for the parenteral, namely intravenous administration. Many parenteral nutrition and drug emulsions on the market confirm the safe use of NE over years. Parenteral emulsions loaded with APIs (active pharmaceutical ingredients) are considered as drug delivery systems (DDS). DDS focuses on the regulation of the in vivo dynamics, such as absorption, distribution, metabolism, and extended bioavailability, thereby improving the effectiveness and the safety of the drugs. Using an emulsion as a DDS, or through the use of surface diversification of the dispersed oil droplets of emulsions, a targeted increase of the API concentration in some parts of the human body can be achieved. This review focuses on NE similar to the marketed once with no or only low amount of additional surfactants beside the emulsifier from a manufacturing point of view (technique, used raw materials).

Parenteral nanoemulsions as promising carriers for brain delivery of risperidone: Design, characterization and in vivo pharmacokinetic evaluation

This paper describes design and evaluation of parenteral lecithin-based nanoemulsions intended for brain delivery of risperidone, a poorly water-soluble psychopharmacological drug. The nanoemulsions were prepared through cold/hot high pressure homogenization and characterized regarding droplet size, polydispersity, surface charge, morphology, drug-vehicle interactions, and physical stability. To estimate the simultaneous influence of nanoemulsion formulation and preparation parameters--co-emulsifier type, aqueous phase type, homogenization temperature--on the critical quality attributes of developed nanoemulsions, a general factorial experimental design was applied. From the established design space and stability data, promising risperidone-loaded nanoemulsions (mean size about 160 nm, size distribution <0.15, zeta potential around -50 mV), containing sodium oleate in the aqueous phase and polysorbate 80, poloxamer 188 or Solutol(®) HS15 as co-emulsifier, were produced by hot homogenization and their ability to improve risperidone delivery to the brain was assessed in rats. Pharmacokinetic study demonstrated erratic brain profiles of risperidone following intraperitoneal administration in selected nanoemulsions, most probably due to their different droplet surface properties (different composition of the stabilizing layer). Namely, polysorbate 80-costabilized nanoemulsion showed increased (1.4-7.4-fold higher) risperidone brain availability compared to other nanoemulsions and drug solution, suggesting this nanoemulsion as a promising carrier worth exploring further for brain targeting.

The critical role of didodecyldimethylammonium bromide on physico-chemical, technological and biological properties of NLC

Exploiting the experimental factorial design and the potentiality of Turbiscan AG Station, we developed and characterized unmodified and DDAB-coated NLC prepared by a low energy organic solvent free phase inversion temperature technique. A 22 full factorial experimental design was developed in order to study the effects of two independent variables (DDAB and ferulic acid) and their interaction on mean particle size and zeta potential values. The factorial planning was validated by ANOVA analysis; the correspondence between the predicted values of size and zeta and those measured experimentally confirmed the validity of the design and the equation applied for its resolution. The DDAB-coated NLC were significantly affected in their physico-chemical properties by the presence of DDAB, as showed by the results of the experimental design. The coated NLC showed higher physical stability with no particles aggregation compared to the unmodified NLC, as demonstrated by Turbiscan(®) AGS measurements. X-ray diffraction, Raman spectroscopy and Cryo-TEM images allowed us to assert that DDAB plays a critical role in increasing the lipids structural order with a consequent enhancement of the NLC physical stability. Furthermore, the results of the in vitro biological studies allow the revisiting of the role of DDAB to the benefit of glioblastoma treatment, due to its efficacy in increasing the NLC uptake and reducing the viability of human glioblastoma cancer cells (U87MG).